feat: add guided learning cockpit

pom.xml

@@ -37,6 +37,35 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-actuator</artifactId>
         </dependency>
+
+        <!-- 参数校验 -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-validation</artifactId>
+        </dependency>
+
+        <!-- 仅用于学习的可选鉴权演示（不影响主流程） -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-security</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.jsonwebtoken</groupId>
+            <artifactId>jjwt-api</artifactId>
+            <version>0.12.3</version>
+        </dependency>
+        <dependency>
+            <groupId>io.jsonwebtoken</groupId>
+            <artifactId>jjwt-impl</artifactId>
+            <version>0.12.3</version>
+            <scope>runtime</scope>
+        </dependency>
+        <dependency>
+            <groupId>io.jsonwebtoken</groupId>
+            <artifactId>jjwt-jackson</artifactId>
+            <version>0.12.3</version>
+            <scope>runtime</scope>
+        </dependency>
         
         <!-- 测试 -->
         <dependency>

springboot.log

@@ -7,25 +7,31 @@
  =========|_|==============|___/=/_/_/_/
  :: Spring Boot ::                (v3.2.0)
 
-2026-03-06T17:09:02.230Z  INFO 1154290 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : Starting DemoApplication v0.0.1-SNAPSHOT using Java 21.0.10 with PID 1154290 (/home/llm/projects/springboot-demo/target/demo-0.0.1-SNAPSHOT.jar started by llm in /home/llm/projects/springboot-demo)
-2026-03-06T17:09:02.380Z  INFO 1154290 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : No active profile set, falling back to 1 default profile: "default"
-2026-03-06T17:10:05.868Z  INFO 1154290 --- [springboot-demo] [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8082 (http)
-2026-03-06T17:10:06.093Z  INFO 1154290 --- [springboot-demo] [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
-2026-03-06T17:10:06.093Z  INFO 1154290 --- [springboot-demo] [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.16]
-2026-03-06T17:10:07.996Z  INFO 1154290 --- [springb2026-03-06T17:10:12.808Z  INFO 1153691 --- [springboot-demo] [           main] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 1 endpoint(s) beneath base path '/actuator'
-2026-03-06T17:10:14.838Z  INFO 1153691 --- [springboot-demo] [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat start2026-03-06T17:10:23.314Z  INFO 1154290 --- [springboot-demo] [           main] o.s.b.a.w.s.WelcomePageHandlerMapping    : Adding welcome page: class path resource [static/index.html]
-2026-03-06T17:10:40.414Z  INFO 1154290 --- [springboot-demo] [           main] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 1 endpoint(s) beneath base path '/actuator'
-2026-03-06T17:10:41.395Z  INFO 1154290 --- [springboot-demo] [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8082 (http) with context path ''
-2026-03-06T17:10:41.541Z  INFO 1154290 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : Started DemoApplication in 116.974 seconds (process running for 133.101)
+2026-03-07T08:12:47.326Z  INFO 1374194 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : Starting DemoApplication v0.0.1-SNAPSHOT using Java 21.0.10 with PID 1374194 (/home/llm/projects/springboot-demo/target/demo-0.0.1-SNAPSHOT.jar started by llm in /home/llm/projects/springboot-demo)
+2026-03-07T08:12:47.356Z  INFO 1374194 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : No active profile set, falling back to 1 default profile: "default"
+2026-03-07T08:13:00.941Z  INFO 1374194 --- [springboot-demo] [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8082 (http)
+2026-03-07T08:13:01.016Z  INFO 1374194 --- [springboot-demo] [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
+2026-03-07T08:13:01.020Z  INFO 1374194 --- [springboot-demo] [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.16]
+2026-03-07T08:13:01.808Z  INFO 1374194 --- [springboot-demo] [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
+2026-03-07T08:13:01.814Z  INFO 1374194 --- [springboot-demo] [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 13966 ms
+2026-03-07T08:13:07.411Z  INFO 1374194 --- [springboot-demo] [           main] o.s.b.a.w.s.WelcomePageHandlerMapping    : Adding welcome page: class path resource [static/index.html]
+2026-03-07T08:13:15.547Z  INFO 1374194 --- [springboot-demo] [           main] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 1 endpoint(s) beneath base path '/actuator'
+2026-03-07T08:13:16.328Z  INFO 1374194 --- [springboot-demo] [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8082 (http) with context path ''
+2026-03-07T08:13:16.450Z  INFO 1374194 --- [springboot-demo] [           main] com.example.demo.DemoApplication         : Started DemoApplication in 33.141 seconds (process running for 36.573)
 [EventListener] Spring Boot 应用启动完成！
-2026-03-06T17:11:05.601Z  INFO 1154290 --- [springboot-demo] [nio-8082-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
-2026-03-06T17:11:05.601Z  INFO 1154290 --- [springboot-demo] [nio-8082-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
-2026-03-06T17:11:05.619Z  INFO 1154290 --- [springboot-demo] [nio-8082-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 13 ms
+2026-03-07T08:13:47.186Z  INFO 1374194 --- [springboot-demo] [nio-8082-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
+2026-03-07T08:13:47.186Z  INFO 1374194 --- [springboot-demo] [nio-8082-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
+2026-03-07T08:13:47.195Z  INFO 1374194 --- [springboot-demo] [nio-8082-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 4 ms
 [AOP-Before] Controller 方法开始: root
   参数: []
 [AOP-AfterReturning] 方法返回: root
   返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
-[AOP-Performance] LearnController.root() 执行耗时: 18ms
+[AOP-Performance] LearnController.root() 执行耗时: 8ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 3ms
 [AOP-Before] Controller 方法开始: root
   参数: []
 [AOP-AfterReturning] 方法返回: root
@@ -35,4 +41,56 @@
   参数: []
 [AOP-AfterReturning] 方法返回: root
   返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
-[AOP-Performance] LearnController.root() 执行耗时: 3ms
+[AOP-Performance] LearnController.root() 执行耗时: 10ms
+[AOP-Before] Controller 方法开始: getAllUsers
+  参数: []
+[AOP-After] Service 方法结束: findAll
+[AOP-Performance] UserService.findAll() 执行耗时: 2ms
+[AOP-AfterReturning] 方法返回: getAllUsers
+  返回值: [com.example.demo.model.User@3616c07a, com.example.demo.model.User@a6b1d0f, com.example.demo.model.User@7935776c]
+[AOP-Performance] UserController.getAllUsers() 执行耗时: 5ms
+[AOP-Before] Controller 方法开始: info
+  参数: []
+[AOP-AfterReturning] 方法返回: info
+  返回值: {app=springboot-demo, endpoints=[Ljava.lang.String;@6c7b5bf1, message=欢迎学习 Spring Boot！}
+[AOP-Performance] LearnController.info() 执行耗时: 2ms
+[AOP-Before] Controller 方法开始: index
+  参数: []
+[AOP-AfterReturning] 方法返回: index
+  返回值: {endpoints=[Ljava.lang.String;@1b97f799, topics=[Ljava.lang.String;@1fa86033, message=Spring Boot 学习中心}
+[AOP-Performance] AopEventController.index() 执行耗时: 11ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 6ms
+[AOP-Before] Controller 方法开始: index
+  参数: []
+[AOP-AfterReturning] 方法返回: index
+  返回值: {endpoints=[Ljava.lang.String;@63de5cba, topics=[Ljava.lang.String;@67e1d419, message=Spring Boot 学习中心}
+[AOP-Performance] AopEventController.index() 执行耗时: 1ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 0ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 0ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 0ms
+[AOP-Before] Controller 方法开始: root
+  参数: []
+[AOP-AfterReturning] 方法返回: root
+  返回值: {aop=https://spring.xiaoxiaoluohao.indevs.in/aop, learn=https://spring.xiaoxiaoluohao.indevs.in/learn, api=https://spring.xiaoxiaoluohao.indevs.in/api/users, message=欢迎来到 Spring Boot 学习脚手架！}
+[AOP-Performance] LearnController.root() 执行耗时: 2ms
+[AOP-Before] Controller 方法开始: index
+  参数: []
+[AOP-AfterReturning] 方法返回: index
+  返回值: {endpoints=[Ljava.lang.String;@22e35681, topics=[Ljava.lang.String;@2214743, message=Spring Boot 学习中心}
+[AOP-Performance] AopEventController.index() 执行耗时: 0ms

src/main/java/com/example/demo/aop/PerformanceAspect.java

@@ -9,61 +9,35 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
-/**
- * 性能监控切面 - 演示 @Around 环绕通知
- * 
- * 学习点：
- * - @Around 最强大的通知类型
- * - ProceedingJoinPoint 控制方法执行
- * - 方法执行时间统计
- */
 @Aspect
 @Component
 public class PerformanceAspect {
-    
-    // 方法执行时间统计
+
     private final Map<String, Long> totalTimes = new ConcurrentHashMap<>();
     private final Map<String, Long> callCounts = new ConcurrentHashMap<>();
-    
-    /**
-     * 环绕通知 - 统计方法执行时间
-     */
+
     @Around("execution(* com.example.demo.controller.*.*(..)) || " +
-            "execution(* com.example.demo.service.*.*(..))")
+        "execution(* com.example.demo.service.*.*(..))")
     public Object measureExecutionTime(ProceedingJoinPoint joinPoint) throws Throwable {
         String methodName = joinPoint.getSignature().toShortString();
-        
         long startTime = System.currentTimeMillis();
-        
+
         try {
-            // 执行目标方法
             Object result = joinPoint.proceed();
-            
-            long endTime = System.currentTimeMillis();
-            long duration = endTime - startTime;
-            
-            // 记录统计
+            long duration = System.currentTimeMillis() - startTime;
             totalTimes.merge(methodName, duration, Long::sum);
             callCounts.merge(methodName, 1L, Long::sum);
-            
-            System.out.println("[AOP-Performance] " + methodName + 
-                " 执行耗时: " + duration + "ms");
-            
+            System.out.println("[AOP-Performance] " + methodName + " completed in " + duration + "ms");
             return result;
-        } catch (Throwable e) {
-            long endTime = System.currentTimeMillis();
-            System.out.println("[AOP-Performance] " + methodName + 
-                " 异常耗时: " + (endTime - startTime) + "ms");
-            throw e;
+        } catch (Throwable error) {
+            long duration = System.currentTimeMillis() - startTime;
+            System.out.println("[AOP-Performance] " + methodName + " failed after " + duration + "ms");
+            throw error;
         }
     }
-    
-    /**
-     * 获取性能统计
-     */
+
     public Map<String, Map<String, Long>> getStatistics() {
         Map<String, Map<String, Long>> stats = new HashMap<>();
-        
         for (String method : totalTimes.keySet()) {
             Map<String, Long> methodStats = new HashMap<>();
             methodStats.put("totalTime", totalTimes.get(method));
@@ -71,7 +45,6 @@ public class PerformanceAspect {
             methodStats.put("avgTime", totalTimes.get(method) / callCounts.get(method));
             stats.put(method, methodStats);
         }
-        
         return stats;
     }
-}
+}

src/main/java/com/example/demo/common/ApiResponse.java

@@ -0,0 +1,22 @@
+package com.example.demo.common;
+
+import java.time.Instant;
+
+public record ApiResponse<T>(
+        int code,
+        String message,
+        T data,
+        Instant timestamp
+) {
+    public static <T> ApiResponse<T> ok(T data) {
+        return new ApiResponse<>(0, "success", data, Instant.now());
+    }
+
+    public static <T> ApiResponse<T> ok(String message, T data) {
+        return new ApiResponse<>(0, message, data, Instant.now());
+    }
+
+    public static ApiResponse<Void> fail(int code, String message) {
+        return new ApiResponse<>(code, message, null, Instant.now());
+    }
+}

src/main/java/com/example/demo/controller/AopEventController.java

@@ -3,175 +3,178 @@ package com.example.demo.controller;
 import com.example.demo.aop.PerformanceAspect;
 import com.example.demo.aop.RateLimitAspect;
 import com.example.demo.aop.RateLimited;
+import com.example.demo.event.UserEventListener;
 import com.example.demo.event.UserEventPublisher;
-import com.example.demo.model.User;
+import com.example.demo.model.UserEvent;
 import com.example.demo.service.UserService;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.web.bind.annotation.*;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
 
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-/**
- * AOP 和事件机制学习控制器
- */
 @RestController
 @RequestMapping("/aop")
 public class AopEventController {
 
-    @Autowired
-    private UserService userService;
+    private final UserService userService;
+    private final UserEventPublisher eventPublisher;
+    private final UserEventListener userEventListener;
+    private final PerformanceAspect performanceAspect;
+    private final RateLimitAspect rateLimitAspect;
 
-    @Autowired
-    private UserEventPublisher eventPublisher;
+    public AopEventController(UserService userService,
+                              UserEventPublisher eventPublisher,
+                              UserEventListener userEventListener,
+                              PerformanceAspect performanceAspect,
+                              RateLimitAspect rateLimitAspect) {
+        this.userService = userService;
+        this.eventPublisher = eventPublisher;
+        this.userEventListener = userEventListener;
+        this.performanceAspect = performanceAspect;
+        this.rateLimitAspect = rateLimitAspect;
+    }
 
-    @Autowired
-    private PerformanceAspect performanceAspect;
-
-    @Autowired
-    private RateLimitAspect rateLimitAspect;
-
-    /**
-     * 学习首页
-     */
     @GetMapping
     public Map<String, Object> index() {
         Map<String, Object> info = new HashMap<>();
-        info.put("message", "Spring Boot 学习中心");
+        info.put("message", "Explore cross-cutting behavior through AOP, events, and rate limiting.");
         info.put("topics", new String[]{
-            "AOP 切面编程",
-            "事件机制",
-            "Bean 生命周期"
+            "AOP advice and performance tracing",
+            "Application events and listener decoupling",
+            "Annotation-driven rate limiting"
         });
         info.put("endpoints", new String[]{
-            "GET  /aop          - AOP 概念说明",
-            "GET  /aop/stats    - 性能统计",
-            "GET  /aop/event    - 事件机制说明",
-            "POST /aop/event/publish - 发布用户事件",
-            "GET  /aop/event/history - 查看事件历史",
-            "GET  /aop/ratelimit    - 限流测试"
+            "GET  /aop/aop",
+            "GET  /aop/aop/stats",
+            "GET  /aop/event",
+            "POST /aop/event/publish",
+            "GET  /aop/event/history",
+            "GET  /aop/ratelimit"
         });
+        info.put("userCount", userService.findAll().size());
         return info;
     }
 
-    // ==================== AOP 示例 ====================
-
-    /**
-     * AOP 概念说明
-     */
     @GetMapping("/aop")
     public Map<String, Object> aopInfo() {
         Map<String, Object> info = new HashMap<>();
-        info.put("title", "AOP 切面编程");
+        info.put("title", "AOP learning notes");
         info.put("concepts", new String[]{
-            "Aspect（切面）: 横切关注点的模块化",
-            "JoinPoint（连接点）: 程序执行的某个点",
-            "Pointcut（切入点）: 匹配连接点的表达式",
-            "Advice（通知）: 在连接点执行的动作",
-            "Weaving（织入）: 将切面应用到目标对象"
+            "Aspect: a reusable cross-cutting module",
+            "Join point: a place where the program can be intercepted",
+            "Pointcut: the matcher that selects join points",
+            "Advice: code that runs before, after, or around the join point",
+            "Weaving: combining the aspect with the target object"
         });
         info.put("adviceTypes", new String[]{
-            "@Before - 方法执行前",
-            "@After - 方法执行后（无论成功或异常）",
-            "@AfterReturning - 方法成功返回后",
-            "@AfterThrowing - 方法抛出异常后",
-            "@Around - 环绕通知（最强大）"
+            "@Before for pre-checks",
+            "@After for cleanup",
+            "@AfterReturning for successful results",
+            "@AfterThrowing for failures",
+            "@Around for timing, wrapping, and total control"
         });
         info.put("useCases", new String[]{
-            "日志记录",
-            "性能监控",
-            "事务管理",
-            "权限检查",
-            "限流控制"
+            "Logging",
+            "Performance measurement",
+            "Authorization checks",
+            "Rate limiting",
+            "Reusable validation"
         });
         return info;
     }
 
-    /**
-     * 查看性能统计
-     */
     @GetMapping("/aop/stats")
     public Map<String, Object> getPerformanceStats() {
         Map<String, Object> result = new HashMap<>();
-        result.put("title", "方法性能统计");
-        result.put("description", "由 PerformanceAspect 自动收集");
+        result.put("title", "Collected performance metrics");
+        result.put("description", "These numbers come from the around advice on controllers and services.");
         result.put("statistics", performanceAspect.getStatistics());
         return result;
     }
 
-    // ==================== 事件机制示例 ====================
-
-    /**
-     * 事件机制说明
-     */
     @GetMapping("/event")
     public Map<String, Object> eventInfo() {
         Map<String, Object> info = new HashMap<>();
-        info.put("title", "Spring 事件机制");
+        info.put("title", "Spring application events");
         info.put("concepts", new String[]{
-            "ApplicationEventPublisher - 事件发布者",
-            "@EventListener - 事件监听器",
-            "@Async - 异步处理事件",
-            "condition - 条件过滤"
+            "ApplicationEventPublisher emits a domain or lifecycle event.",
+            "@EventListener reacts without tight coupling to the caller.",
+            "@Async lets slow follow-up work happen outside the request path.",
+            "Conditions help one listener focus on one event type."
         });
         info.put("benefits", new String[]{
-            "解耦：发布者和监听者互不依赖",
-            "扩展：新增监听器无需修改发布者",
-            "异步：耗时操作不阻塞主流程",
-            "测试：更容易进行单元测试"
-        });
-        info.put("eventTypes", new String[]{
-            "CREATED - 用户创建",
-            "UPDATED - 用户更新",
-            "DELETED - 用户删除",
-            "LOGIN - 用户登录"
+            "Controllers stay smaller.",
+            "Listeners can grow independently.",
+            "The request flow stays responsive.",
+            "Side effects become easier to test."
         });
+        info.put("eventTypes", UserEvent.Type.values());
         return info;
     }
 
-    /**
-     * 发布用户事件
-     */
     @PostMapping("/event/publish")
     public Map<String, Object> publishEvent(
-            @RequestParam Long userId,
-            @RequestParam String userName,
-            @RequestParam(defaultValue = "LOGIN") String eventType
+        @RequestParam Long userId,
+        @RequestParam String userName,
+        @RequestParam(defaultValue = "LOGIN") String eventType
     ) {
-        eventPublisher.publishUserLogin(userId, userName);
+        UserEvent.Type type = resolveType(eventType);
+        String detail = switch (type) {
+            case CREATED -> "User was created through the demo flow";
+            case UPDATED -> "User profile was updated through the demo flow";
+            case DELETED -> "User was removed through the demo flow";
+            case LOGIN -> "User signed in through the demo flow";
+        };
+        eventPublisher.publishUserEvent(userId, userName, type, detail);
 
         Map<String, Object> result = new HashMap<>();
-        result.put("message", "事件已发布");
-        result.put("eventType", eventType);
+        result.put("message", "Event published successfully.");
+        result.put("eventType", type.name());
         result.put("userId", userId);
         result.put("userName", userName);
+        result.put("historySize", userEventListener.getEventHistory().size());
         return result;
     }
 
-    /**
-     * 查看事件历史
-     */
     @GetMapping("/event/history")
     public Map<String, Object> getEventHistory() {
+        List<Map<String, Object>> items = userEventListener.getEventHistory().stream()
+            .map(event -> Map.<String, Object>of(
+                "type", event.getType().name(),
+                "userId", event.getUserId(),
+                "userName", event.getUserName(),
+                "detail", event.getDetail(),
+                "timestamp", event.getTimestamp().toString()
+            ))
+            .toList();
+
         Map<String, Object> result = new HashMap<>();
-        result.put("title", "事件历史记录");
-        result.put("note", "由 UserEventListener 自动记录");
+        result.put("title", "Recent user event history");
+        result.put("total", items.size());
+        result.put("items", items);
         return result;
     }
 
-    // ==================== 限流示例 ====================
-
-    /**
-     * 限流测试接口
-     */
     @GetMapping("/ratelimit")
-    @RateLimited(value = 10, message = "测试限流：每分钟最多10次")
+    @RateLimited(value = 10, message = "Demo limit reached: only 10 requests per minute are allowed.")
     public Map<String, Object> testRateLimit() {
         Map<String, Object> result = new HashMap<>();
-        result.put("message", "请求成功");
-        result.put("note", "使用 @RateLimited 注解");
+        result.put("message", "Rate-limited endpoint executed successfully.");
+        result.put("note", "The @RateLimited annotation wraps this method through an aspect.");
         result.put("rateLimitStatus", rateLimitAspect.getRateLimitStatus());
         return result;
     }
-}
+
+    private UserEvent.Type resolveType(String rawType) {
+        try {
+            return UserEvent.Type.valueOf(rawType.trim().toUpperCase());
+        } catch (Exception ignored) {
+            return UserEvent.Type.LOGIN;
+        }
+    }
+}

src/main/java/com/example/demo/controller/LearnController.java

@@ -1,116 +1,120 @@
 package com.example.demo.controller;
 
 import org.springframework.beans.factory.annotation.Value;
-import org.springframework.web.bind.annotation.*;
+import org.springframework.web.bind.annotation.CookieValue;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
 
 import java.util.HashMap;
 import java.util.Map;
 
-/**
- * 学习示例控制器
- * 
- * 学习点：
- * - 各种参数接收方式
- * - 配置注入
- * - 响应格式
- */
 @RestController
 public class LearnController {
 
-    // 从配置文件注入值
     @Value("${spring.application.name:demo}")
     private String appName;
 
-    /**
-     * 根路径 - 重定向到学习中心
-     */
-    @GetMapping("/")
+    @GetMapping("/learn/root")
     public Map<String, Object> root() {
         Map<String, Object> info = new HashMap<>();
-        info.put("message", "欢迎来到 Spring Boot 学习脚手架！");
-        info.put("learn", "https://spring.xiaoxiaoluohao.indevs.in/learn");
-        info.put("aop", "https://spring.xiaoxiaoluohao.indevs.in/aop");
-        info.put("api", "https://spring.xiaoxiaoluohao.indevs.in/api/users");
+        info.put("message", "Welcome to the Spring Boot learning workspace.");
+        info.put("homePage", "/");
+        info.put("userLab", "/users.html");
+        info.put("aopLab", "/aop.html");
+        info.put("eventLab", "/events.html");
+        info.put("learnApi", "/learn");
         return info;
     }
 
-    // GET /learn - API 信息
     @GetMapping("/learn")
     public Map<String, Object> info() {
         Map<String, Object> info = new HashMap<>();
         info.put("app", appName);
-        info.put("message", "欢迎学习 Spring Boot！");
+        info.put("message", "Use this endpoint family to compare common Spring MVC input patterns.");
+        info.put("learningGoals", new String[]{
+            "Understand how query parameters, path variables, headers, cookies, and JSON bodies are mapped.",
+            "Compare normal responses with handled exceptions.",
+            "Connect the browser, controller method signature, and serialized JSON output."
+        });
         info.put("endpoints", new String[]{
-            "GET  /learn/params?name=xxx&age=18 - 参数示例",
-            "POST /learn/body - JSON 请求体示例",
-            "GET  /learn/path/{id} - 路径变量示例",
-            "GET  /learn/header - 请求头示例",
-            "GET  /learn/cookie - Cookie 示例"
+            "GET  /learn/params?name=alex&age=18",
+            "POST /learn/body",
+            "GET  /learn/path/{id}",
+            "GET  /learn/header",
+            "GET  /learn/cookie",
+            "GET  /learn/exception",
+            "POST /api/auth/login",
+            "GET  /api/secure/me"
         });
         return info;
     }
 
-    // GET /learn/params?name=xxx&age=18 - 查询参数
     @GetMapping("/learn/params")
     public Map<String, Object> params(
-            @RequestParam(required = false, defaultValue = "游客") String name,
-            @RequestParam(required = false, defaultValue = "0") Integer age
+        @RequestParam(required = false, defaultValue = "guest") String name,
+        @RequestParam(required = false, defaultValue = "0") Integer age
     ) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@RequestParam");
         result.put("name", name);
         result.put("age", age);
-        result.put("tip", "使用 @RequestParam 接收查询参数");
+        result.put("tip", "Query parameters are useful for filters, pagination, and optional toggles.");
         return result;
     }
 
-    // POST /learn/body - 请求体
     @PostMapping("/learn/body")
     public Map<String, Object> body(@RequestBody Map<String, Object> data) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@RequestBody");
         result.put("received", data);
-        result.put("tip", "使用 @RequestBody 接收 JSON 请求体");
+        result.put("tip", "JSON request bodies fit create and update flows where the payload has structure.");
         return result;
     }
 
-    // GET /learn/path/{id} - 路径变量
     @GetMapping("/learn/path/{id}")
     public Map<String, Object> path(@PathVariable String id) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@PathVariable");
         result.put("id", id);
-        result.put("tip", "使用 @PathVariable 接收路径变量");
+        result.put("tip", "Path variables usually identify a concrete resource such as a user, order, or lesson.");
         return result;
     }
 
-    // GET /learn/header - 请求头
     @GetMapping("/learn/header")
     public Map<String, Object> header(@RequestHeader(value = "User-Agent", required = false) String userAgent) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@RequestHeader");
         result.put("userAgent", userAgent);
-        result.put("tip", "使用 @RequestHeader 获取请求头");
+        result.put("tip", "Headers often carry auth context, tracing ids, and client metadata.");
         return result;
     }
 
-    // GET /learn/cookie - Cookie
     @GetMapping("/learn/cookie")
     public Map<String, Object> cookie(@CookieValue(value = "JSESSIONID", required = false) String sessionId) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@CookieValue");
         result.put("sessionId", sessionId);
-        result.put("tip", "使用 @CookieValue 获取 Cookie");
+        result.put("tip", "Cookies help explain browser session state and why a request may look authenticated.");
         return result;
     }
 
-    // GET /learn/exception - 异常处理
     @GetMapping("/learn/exception")
     public String exception() {
-        throw new RuntimeException("这是一个测试异常");
+        throw new RuntimeException("Intentional demo exception from /learn/exception");
     }
 
-    // 全局异常处理
     @ExceptionHandler(RuntimeException.class)
     public Map<String, Object> handleException(RuntimeException e) {
         Map<String, Object> result = new HashMap<>();
+        result.put("pattern", "@ExceptionHandler");
         result.put("error", e.getMessage());
-        result.put("tip", "使用 @ExceptionHandler 处理异常");
+        result.put("tip", "Spring can convert thrown exceptions into structured API responses without leaking stack traces.");
         return result;
     }
-}
+}

src/main/java/com/example/demo/controller/UserController.java

@@ -1,64 +1,62 @@
 package com.example.demo.controller;
 
+import com.example.demo.common.ApiResponse;
+import com.example.demo.dto.UserRequest;
+import com.example.demo.dto.UserStatsResponse;
 import com.example.demo.model.User;
 import com.example.demo.service.UserService;
-import org.springframework.beans.factory.annotation.Autowired;
+import jakarta.validation.Valid;
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
 
-/**
- * 用户控制器 - RESTful API 示例
- * 
- * 学习点：
- * - @RestController: 组合了 @Controller 和 @ResponseBody
- * - @RequestMapping: 路由映射
- * - @PathVariable: 路径变量
- * - @RequestParam: 查询参数
- * - @RequestBody: 请求体
- */
 @RestController
 @RequestMapping("/api/users")
 public class UserController {
 
-    @Autowired
-    private UserService userService;
+    private final UserService userService;
+
+    public UserController(UserService userService) {
+        this.userService = userService;
+    }
 
-    // GET /api/users - 获取所有用户
     @GetMapping
-    public List<User> getAllUsers() {
-        return userService.findAll();
+    public ApiResponse<List<User>> getAllUsers() {
+        return ApiResponse.ok(userService.findAll());
     }
 
-    // GET /api/users/{id} - 获取单个用户
-    @GetMapping("/{id}")
-    public User getUserById(@PathVariable Long id) {
-        return userService.findById(id);
+    @GetMapping("/stats")
+    public ApiResponse<UserStatsResponse> getUserStats() {
+        return ApiResponse.ok(userService.getStats());
     }
 
-    // POST /api/users - 创建用户
-    @PostMapping
-    public User createUser(@RequestBody User user) {
-        return userService.save(user);
-    }
-
-    // PUT /api/users/{id} - 更新用户
-    @PutMapping("/{id}")
-    public User updateUser(@PathVariable Long id, @RequestBody User user) {
-        user.setId(id);
-        return userService.save(user);
-    }
-
-    // DELETE /api/users/{id} - 删除用户
-    @DeleteMapping("/{id}")
-    public String deleteUser(@PathVariable Long id) {
-        userService.delete(id);
-        return "用户 " + id + " 已删除";
-    }
-
-    // GET /api/users/search?name=xxx - 搜索用户
     @GetMapping("/search")
-    public List<User> searchUsers(@RequestParam String name) {
-        return userService.findByName(name);
+    public ApiResponse<List<User>> searchUsers(@RequestParam(required = false) String keyword,
+                                               @RequestParam(required = false) String name) {
+        String term = keyword != null && !keyword.isBlank() ? keyword : name;
+        return ApiResponse.ok(userService.search(term));
     }
-}
+
+    @GetMapping("/{id}")
+    public ApiResponse<User> getUserById(@PathVariable Long id) {
+        return ApiResponse.ok(userService.findById(id));
+    }
+
+    @PostMapping
+    public ApiResponse<User> createUser(@Valid @RequestBody UserRequest request) {
+        User user = new User(null, request.name(), request.email(), request.age());
+        return ApiResponse.ok("User created successfully", userService.create(user));
+    }
+
+    @PutMapping("/{id}")
+    public ApiResponse<User> updateUser(@PathVariable Long id, @Valid @RequestBody UserRequest request) {
+        User user = new User(id, request.name(), request.email(), request.age());
+        return ApiResponse.ok("User updated successfully", userService.update(id, user));
+    }
+
+    @DeleteMapping("/{id}")
+    public ApiResponse<Void> deleteUser(@PathVariable Long id) {
+        userService.delete(id);
+        return ApiResponse.ok("User deleted successfully", null);
+    }
+}

src/main/java/com/example/demo/controller/auth/LearningAuthController.java

@@ -0,0 +1,45 @@
+package com.example.demo.controller.auth;
+
+import com.example.demo.common.ApiResponse;
+import com.example.demo.dto.auth.LoginRequest;
+import com.example.demo.security.LearningJwtUtil;
+import jakarta.validation.Valid;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.Map;
+
+@RestController
+@RequestMapping("/api/auth")
+public class LearningAuthController {
+
+    private final LearningJwtUtil jwtUtil;
+
+    public LearningAuthController(LearningJwtUtil jwtUtil) {
+        this.jwtUtil = jwtUtil;
+    }
+
+    @PostMapping("/login")
+    public ApiResponse<Map<String, Object>> login(@Valid @RequestBody LoginRequest req) {
+        // 学习演示：仅做最小账号检查
+        if (!(("admin".equals(req.username()) && "admin123".equals(req.password()))
+                || ("user".equals(req.username()) && "user123".equals(req.password())))) {
+            return new ApiResponse<>(401, "用户名或密码错误", null, java.time.Instant.now());
+        }
+        String token = jwtUtil.generateToken(req.username());
+        return ApiResponse.ok(Map.of(
+                "token", token,
+                "type", "Bearer",
+                "username", req.username(),
+                "tip", "在请求头中加入 Authorization: Bearer <token> 访问 /api/secure/**"
+        ));
+    }
+
+    @GetMapping("/mode")
+    public ApiResponse<Map<String, Object>> mode() {
+        return ApiResponse.ok(Map.of(
+                "mode", "learning-jwt",
+                "protectedPath", "/api/secure/**",
+                "defaultAccounts", "admin/admin123, user/user123"
+        ));
+    }
+}

src/main/java/com/example/demo/controller/auth/SecureDemoController.java

@@ -0,0 +1,23 @@
+package com.example.demo.controller.auth;
+
+import com.example.demo.common.ApiResponse;
+import org.springframework.security.core.Authentication;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Map;
+
+@RestController
+@RequestMapping("/api/secure")
+public class SecureDemoController {
+
+    @GetMapping("/me")
+    public ApiResponse<Map<String, Object>> me(Authentication authentication) {
+        return ApiResponse.ok(Map.of(
+                "principal", authentication.getName(),
+                "authorities", authentication.getAuthorities(),
+                "message", "你已通过学习用 JWT 鉴权"
+        ));
+    }
+}

src/main/java/com/example/demo/dto/UserRequest.java

@@ -0,0 +1,24 @@
+package com.example.demo.dto;
+
+import jakarta.validation.constraints.Email;
+import jakarta.validation.constraints.Max;
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Size;
+
+public record UserRequest(
+        @NotBlank(message = "Name is required")
+        @Size(max = 40, message = "Name must be at most 40 characters")
+        String name,
+
+        @NotBlank(message = "Email is required")
+        @Email(message = "Email format is invalid")
+        String email,
+
+        @NotNull(message = "Age is required")
+        @Min(value = 1, message = "Age must be at least 1")
+        @Max(value = 120, message = "Age must be at most 120")
+        Integer age
+) {
+}

src/main/java/com/example/demo/dto/UserStatsResponse.java

@@ -0,0 +1,9 @@
+package com.example.demo.dto;
+
+public record UserStatsResponse(
+        long totalUsers,
+        long adults,
+        long underThirty,
+        double averageAge
+) {
+}

src/main/java/com/example/demo/dto/auth/LoginRequest.java

@@ -0,0 +1,8 @@
+package com.example.demo.dto.auth;
+
+import jakarta.validation.constraints.NotBlank;
+
+public record LoginRequest(
+        @NotBlank(message = "用户名不能为空") String username,
+        @NotBlank(message = "密码不能为空") String password
+) {}

src/main/java/com/example/demo/event/UserEventListener.java

@@ -1,80 +1,50 @@
 package com.example.demo.event;
 
 import com.example.demo.model.UserEvent;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
 import org.springframework.context.event.EventListener;
 import org.springframework.scheduling.annotation.Async;
 import org.springframework.stereotype.Component;
-import org.springframework.context.event.ContextRefreshedEvent;
-import org.springframework.boot.context.event.ApplicationReadyEvent;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
 
-/**
- * 事件监听器 - 演示如何监听事件
- * 
- * 学习点：
- * - @EventListener 注解
- * - @Async 异步处理
- * - 多监听器协作
- * - 事件驱动架构的优势
- */
 @Component
 public class UserEventListener {
-    
-    // 存储事件历史（演示用）
+
     private final List<UserEvent> eventHistory = new CopyOnWriteArrayList<>();
-    
-    /**
-     * 监听用户事件 - 日志记录
-     */
+
     @EventListener
     public void handleUserEvent(UserEvent event) {
-        System.out.println("[EventListener] 收到事件: " + event.getType() + 
-            " - 用户: " + event.getUserName() + 
-            " - 时间: " + event.getTimestamp());
-        
-        // 记录到历史
+        System.out.println("[EventListener] Received " + event.getType() + " for " + event.getUserName()
+            + " at " + event.getTimestamp());
         eventHistory.add(event);
     }
-    
-    /**
-     * 监听用户创建事件 - 发送欢迎邮件（模拟）
-     */
+
     @EventListener(condition = "#event.type == T(com.example.demo.model.UserEvent$Type).CREATED")
     @Async
     public void handleUserCreated(UserEvent event) {
-        System.out.println("[EmailService] 发送欢迎邮件给: " + event.getUserName());
-        // 模拟邮件发送耗时
+        System.out.println("[EmailService] Simulate welcome email for " + event.getUserName());
         try {
             Thread.sleep(100);
-        } catch (InterruptedException e) {
+        } catch (InterruptedException exception) {
             Thread.currentThread().interrupt();
         }
-        System.out.println("[EmailService] 欢迎邮件发送完成");
+        System.out.println("[EmailService] Welcome email finished for " + event.getUserName());
     }
-    
-    /**
-     * 监听用户登录事件 - 更新登录统计
-     */
+
     @EventListener(condition = "#event.type == T(com.example.demo.model.UserEvent$Type).LOGIN")
     public void handleUserLogin(UserEvent event) {
-        System.out.println("[LoginTracker] 记录用户登录: " + event.getUserName());
+        System.out.println("[LoginTracker] Track login for " + event.getUserName());
     }
-    
-    /**
-     * 监听应用启动完成事件
-     */
+
     @EventListener
     public void onApplicationReady(ApplicationReadyEvent event) {
-        System.out.println("[EventListener] Spring Boot 应用启动完成！");
+        System.out.println("[EventListener] Spring Boot learning demo is ready.");
     }
-    
-    /**
-     * 获取事件历史
-     */
+
     public List<UserEvent> getEventHistory() {
         return new ArrayList<>(eventHistory);
     }
-}
+}

src/main/java/com/example/demo/event/UserEventPublisher.java

@@ -1,55 +1,30 @@
 package com.example.demo.event;
 
 import com.example.demo.model.UserEvent;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.stereotype.Component;
-import org.springframework.beans.factory.annotation.Autowired;
 
-/**
- * 事件发布器 - 演示如何发布事件
- * 
- * 学习点：
- * - ApplicationEventPublisher 接口
- * - 依赖注入发布器
- * - 解耦：发布者不需要知道监听者
- */
 @Component
 public class UserEventPublisher {
-    
+
     @Autowired
     private ApplicationEventPublisher eventPublisher;
-    
-    /**
-     * 发布用户事件
-     */
+
     public void publishEvent(UserEvent event) {
-        System.out.println("[EventPublisher] 发布事件: " + event.getType() + " - " + event.getUserName());
+        System.out.println("[EventPublisher] Publish event " + event.getType() + " for " + event.getUserName());
         eventPublisher.publishEvent(event);
     }
-    
-    /**
-     * 便捷方法：发布用户创建事件
-     */
+
+    public void publishUserEvent(Long userId, String userName, UserEvent.Type type, String detail) {
+        publishEvent(new UserEvent(type, userId, userName, detail));
+    }
+
     public void publishUserCreated(Long userId, String userName) {
-        UserEvent event = new UserEvent(
-            UserEvent.Type.CREATED,
-            userId,
-            userName,
-            "新用户注册成功"
-        );
-        publishEvent(event);
+        publishUserEvent(userId, userName, UserEvent.Type.CREATED, "User created successfully");
     }
-    
-    /**
-     * 便捷方法：发布用户登录事件
-     */
+
     public void publishUserLogin(Long userId, String userName) {
-        UserEvent event = new UserEvent(
-            UserEvent.Type.LOGIN,
-            userId,
-            userName,
-            "用户登录成功"
-        );
-        publishEvent(event);
+        publishUserEvent(userId, userName, UserEvent.Type.LOGIN, "User login succeeded");
     }
-}
+}

src/main/java/com/example/demo/exception/DuplicateEmailException.java

@@ -0,0 +1,7 @@
+package com.example.demo.exception;
+
+public class DuplicateEmailException extends RuntimeException {
+    public DuplicateEmailException(String message) {
+        super(message);
+    }
+}

src/main/java/com/example/demo/exception/GlobalExceptionHandler.java

@@ -0,0 +1,46 @@
+package com.example.demo.exception;
+
+import com.example.demo.common.ApiResponse;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.validation.FieldError;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.Map;
+
+@RestControllerAdvice
+public class GlobalExceptionHandler {
+
+    @ExceptionHandler(ResourceNotFoundException.class)
+    public ResponseEntity<ApiResponse<Void>> handleNotFound(ResourceNotFoundException exception) {
+        return ResponseEntity.status(HttpStatus.NOT_FOUND)
+                .body(ApiResponse.fail(404, exception.getMessage()));
+    }
+
+    @ExceptionHandler(DuplicateEmailException.class)
+    public ResponseEntity<ApiResponse<Void>> handleDuplicateEmail(DuplicateEmailException exception) {
+        return ResponseEntity.status(HttpStatus.CONFLICT)
+                .body(ApiResponse.fail(409, exception.getMessage()));
+    }
+
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    public ResponseEntity<ApiResponse<Map<String, String>>> handleValidation(MethodArgumentNotValidException exception) {
+        Map<String, String> errors = new HashMap<>();
+        for (FieldError error : exception.getBindingResult().getFieldErrors()) {
+            errors.put(error.getField(), error.getDefaultMessage());
+        }
+
+        return ResponseEntity.badRequest()
+                .body(new ApiResponse<>(400, "Validation failed", errors, Instant.now()));
+    }
+
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<ApiResponse<Void>> handleAny(Exception exception) {
+        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
+                .body(ApiResponse.fail(500, "Unexpected server error"));
+    }
+}

src/main/java/com/example/demo/exception/ResourceNotFoundException.java

@@ -0,0 +1,7 @@
+package com.example.demo.exception;
+
+public class ResourceNotFoundException extends RuntimeException {
+    public ResourceNotFoundException(String message) {
+        super(message);
+    }
+}

src/main/java/com/example/demo/security/LearningJwtFilter.java

@@ -0,0 +1,62 @@
+package com.example.demo.security;
+
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
+import org.springframework.stereotype.Component;
+import org.springframework.util.StringUtils;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import java.io.IOException;
+import java.util.List;
+
+@Component
+public class LearningJwtFilter extends OncePerRequestFilter {
+
+    private final LearningJwtUtil jwtUtil;
+
+    public LearningJwtFilter(LearningJwtUtil jwtUtil) {
+        this.jwtUtil = jwtUtil;
+    }
+
+    @Override
+    protected boolean shouldNotFilter(HttpServletRequest request) {
+        return !request.getRequestURI().startsWith("/api/secure/");
+    }
+
+    @Override
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
+            throws ServletException, IOException {
+        String auth = request.getHeader("Authorization");
+        if (!StringUtils.hasText(auth) || !auth.startsWith("Bearer ")) {
+            response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
+            response.setContentType("application/json;charset=UTF-8");
+            response.getWriter().write("{\"code\":401,\"message\":\"缺少或非法 Authorization\"}");
+            return;
+        }
+
+        String token = auth.substring(7);
+        if (!jwtUtil.validate(token)) {
+            response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
+            response.setContentType("application/json;charset=UTF-8");
+            response.getWriter().write("{\"code\":401,\"message\":\"Token 无效或过期\"}");
+            return;
+        }
+
+        String username = jwtUtil.username(token);
+        var authToken = new UsernamePasswordAuthenticationToken(
+                username,
+                null,
+                List.of(new SimpleGrantedAuthority("ROLE_USER"))
+        );
+        authToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
+        SecurityContextHolder.getContext().setAuthentication(authToken);
+
+        filterChain.doFilter(request, response);
+    }
+}

src/main/java/com/example/demo/security/LearningJwtUtil.java

@@ -0,0 +1,54 @@
+package com.example.demo.security;
+
+import io.jsonwebtoken.Claims;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.security.Keys;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+import javax.crypto.SecretKey;
+import java.nio.charset.StandardCharsets;
+import java.util.Date;
+import java.util.Map;
+
+@Component
+public class LearningJwtUtil {
+
+    @Value("${learning.auth.jwt.secret}")
+    private String secret;
+
+    @Value("${learning.auth.jwt.expiration:86400000}")
+    private long expiration;
+
+    private SecretKey key() {
+        return Keys.hmacShaKeyFor(secret.getBytes(StandardCharsets.UTF_8));
+    }
+
+    public String generateToken(String username) {
+        Date now = new Date();
+        return Jwts.builder()
+                .claims(Map.of("username", username))
+                .subject(username)
+                .issuedAt(now)
+                .expiration(new Date(now.getTime() + expiration))
+                .signWith(key(), Jwts.SIG.HS256)
+                .compact();
+    }
+
+    public boolean validate(String token) {
+        try {
+            parse(token);
+            return true;
+        } catch (Exception e) {
+            return false;
+        }
+    }
+
+    public String username(String token) {
+        return parse(token).getSubject();
+    }
+
+    private Claims parse(String token) {
+        return Jwts.parser().verifyWith(key()).build().parseSignedClaims(token).getPayload();
+    }
+}

src/main/java/com/example/demo/security/LearningSecurityConfig.java

@@ -0,0 +1,38 @@
+package com.example.demo.security;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
+import org.springframework.security.config.http.SessionCreationPolicy;
+import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+@Configuration
+@ConditionalOnProperty(name = "learning.auth.enabled", havingValue = "true", matchIfMissing = true)
+public class LearningSecurityConfig {
+
+    private final LearningJwtFilter learningJwtFilter;
+
+    public LearningSecurityConfig(LearningJwtFilter learningJwtFilter) {
+        this.learningJwtFilter = learningJwtFilter;
+    }
+
+    @Bean
+    public SecurityFilterChain learningSecurityFilterChain(HttpSecurity http) throws Exception {
+        http
+                .csrf(AbstractHttpConfigurer::disable)
+                .sessionManagement(s -> s.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
+                .authorizeHttpRequests(auth -> auth
+                        .requestMatchers(
+                                "/", "/home", "/learn/**", "/aop/**", "/api/users/**", "/api/health",
+                                "/api/auth/**", "/actuator/**", "/index.html", "/users.html", "/aop.html", "/events.html"
+                        ).permitAll()
+                        .requestMatchers("/api/secure/**").authenticated()
+                        .anyRequest().permitAll()
+                )
+                .addFilterBefore(learningJwtFilter, UsernamePasswordAuthenticationFilter.class);
+        return http.build();
+    }
+}

src/main/java/com/example/demo/service/UserService.java

@@ -1,69 +1,112 @@
 package com.example.demo.service;
 
+import com.example.demo.dto.UserStatsResponse;
+import com.example.demo.exception.DuplicateEmailException;
+import com.example.demo.exception.ResourceNotFoundException;
 import com.example.demo.model.User;
 import org.springframework.stereotype.Service;
 
-import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.stream.Collectors;
 
-/**
- * 用户服务 - 业务逻辑层
- * 
- * 学习点：
- * - @Service: 标记为服务层组件，自动注册为 Bean
- * - 依赖注入：Controller 通过 @Autowired 注入此服务
- * - 分层架构：Controller -> Service -> Repository
- */
 @Service
 public class UserService {
 
-    // 内存存储（演示用，实际项目用数据库）
-    private final List<User> users = new ArrayList<>();
+    private final List<User> users = new CopyOnWriteArrayList<>();
     private final AtomicLong idGenerator = new AtomicLong(1);
 
     public UserService() {
-        // 初始化一些测试数据
-        users.add(new User(idGenerator.getAndIncrement(), "张三", "zhangsan@example.com", 25));
-        users.add(new User(idGenerator.getAndIncrement(), "李四", "lisi@example.com", 30));
-        users.add(new User(idGenerator.getAndIncrement(), "王五", "wangwu@example.com", 28));
+        users.add(new User(idGenerator.getAndIncrement(), "Alice Chen", "alice@example.com", 25));
+        users.add(new User(idGenerator.getAndIncrement(), "Brandon Li", "brandon@example.com", 30));
+        users.add(new User(idGenerator.getAndIncrement(), "Carol Wang", "carol@example.com", 28));
     }
 
     public List<User> findAll() {
-        return new ArrayList<>(users);
+        return users.stream()
+                .sorted((left, right) -> Long.compare(left.getId(), right.getId()))
+                .collect(Collectors.toList());
     }
 
     public User findById(Long id) {
         return users.stream()
-                .filter(u -> u.getId().equals(id))
+                .filter(user -> user.getId().equals(id))
                 .findFirst()
-                .orElse(null);
+                .orElseThrow(() -> new ResourceNotFoundException("User not found: id=" + id));
     }
 
-    public List<User> findByName(String name) {
+    public List<User> search(String keyword) {
+        if (keyword == null || keyword.isBlank()) {
+            return findAll();
+        }
+
+        String normalizedKeyword = keyword.trim().toLowerCase();
         return users.stream()
-                .filter(u -> u.getName().contains(name))
+                .filter(user -> user.getName().toLowerCase().contains(normalizedKeyword)
+                        || user.getEmail().toLowerCase().contains(normalizedKeyword))
+                .sorted((left, right) -> Long.compare(left.getId(), right.getId()))
                 .collect(Collectors.toList());
     }
 
-    public User save(User user) {
-        if (user.getId() == null) {
-            user.setId(idGenerator.getAndIncrement());
-            users.add(user);
-        } else {
-            // 更新
-            for (int i = 0; i < users.size(); i++) {
-                if (users.get(i).getId().equals(user.getId())) {
-                    users.set(i, user);
-                    break;
-                }
+    public User create(User user) {
+        ensureEmailAvailable(user.getEmail(), null);
+        User normalized = normalize(user, idGenerator.getAndIncrement());
+        users.add(normalized);
+        return normalized;
+    }
+
+    public User update(Long id, User user) {
+        findById(id);
+        ensureEmailAvailable(user.getEmail(), id);
+
+        User normalized = normalize(user, id);
+        for (int index = 0; index < users.size(); index++) {
+            if (users.get(index).getId().equals(id)) {
+                users.set(index, normalized);
+                return normalized;
             }
         }
-        return user;
+
+        throw new ResourceNotFoundException("User not found: id=" + id);
     }
 
     public void delete(Long id) {
-        users.removeIf(u -> u.getId().equals(id));
+        boolean removed = users.removeIf(user -> user.getId().equals(id));
+        if (!removed) {
+            throw new ResourceNotFoundException("User not found: id=" + id);
+        }
     }
-}
+
+    public UserStatsResponse getStats() {
+        long totalUsers = users.size();
+        long adults = users.stream().filter(user -> user.getAge() >= 18).count();
+        long underThirty = users.stream().filter(user -> user.getAge() < 30).count();
+        double averageAge = users.stream()
+                .mapToInt(User::getAge)
+                .average()
+                .orElse(0.0);
+
+        return new UserStatsResponse(totalUsers, adults, underThirty, averageAge);
+    }
+
+    private void ensureEmailAvailable(String email, Long currentUserId) {
+        String normalizedEmail = email == null ? "" : email.trim().toLowerCase();
+        boolean exists = users.stream()
+                .anyMatch(user -> user.getEmail().equalsIgnoreCase(normalizedEmail)
+                        && (currentUserId == null || !user.getId().equals(currentUserId)));
+
+        if (exists) {
+            throw new DuplicateEmailException("A user with email " + normalizedEmail + " already exists.");
+        }
+    }
+
+    private User normalize(User user, Long id) {
+        return new User(
+                id,
+                user.getName().trim(),
+                user.getEmail().trim().toLowerCase(),
+                user.getAge()
+        );
+    }
+}

src/main/resources/application.properties

@@ -1,2 +1,10 @@
 server.port=8082
 spring.application.name=springboot-demo
+
+# 学习友好：默认只保护 /api/secure/**
+learning.auth.enabled=true
+learning.auth.jwt.secret=demo-learning-secret-key-demo-learning-secret-key
+learning.auth.jwt.expiration=86400000
+
+# 避免默认生成密码干扰学习输出
+spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.security.servlet.UserDetailsServiceAutoConfiguration

src/main/resources/static/aop.html

@@ -1,177 +1,229 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="en">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>AOP 切面编程 - Spring Boot</title>
+    <title>Spring AOP Lab</title>
     <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 900px; margin: 0 auto; padding: 20px; background: #f5f5f5; }
-        h1 { color: #6DB33F; margin: 20px 0; }
-        h2 { color: #333; border-bottom: 2px solid #6DB33F; padding-bottom: 10px; margin: 20px 0 15px; }
-        h3 { color: #6DB33F; margin: 15px 0 10px; }
-        .card { background: white; padding: 25px; margin: 15px 0; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
-        .btn { display: inline-block; padding: 12px 24px; border-radius: 8px; text-decoration: none; font-weight: 500; cursor: pointer; border: none; }
-        .btn-primary { background: #6DB33F; color: white; }
-        .btn-primary:hover { background: #5da32f; }
-        .btn-info { background: #17a2b8; color: white; }
-        code { background: #f0f0f0; padding: 2px 8px; border-radius: 4px; font-family: 'Fira Code', monospace; }
-        pre { background: #2d2d2d; color: #f8f8f2; padding: 20px; border-radius: 8px; overflow-x: auto; margin: 15px 0; }
-        pre code { background: none; color: inherit; }
-        table { width: 100%; border-collapse: collapse; margin: 15px 0; }
-        th, td { border: 1px solid #ddd; padding: 12px; text-align: left; }
-        th { background: #6DB33F; color: white; }
-        tr:nth-child(even) { background: #f9f9f9; }
-        .tip { background: #e7f3ff; padding: 15px; border-radius: 8px; margin: 15px 0; border-left: 4px solid #6DB33F; }
-        .warn { background: #fff3cd; padding: 15px; border-radius: 8px; margin: 15px 0; border-left: 4px solid #ffc107; }
-        .result-box { background: #2d2d2d; color: #f8f8f2; padding: 15px; border-radius: 8px; font-family: monospace; white-space: pre-wrap; margin-top: 10px; }
-        .nav { margin-bottom: 20px; }
-        .nav a { margin-right: 15px; color: #6DB33F; text-decoration: none; }
-        .nav a:hover { text-decoration: underline; }
+        :root {
+            --bg: #eef7ef;
+            --panel: rgba(255,255,255,0.95);
+            --line: #d8e7d8;
+            --text: #102033;
+            --muted: #5c7184;
+            --brand: #3f8f2c;
+            --accent: #0f67b5;
+            --shadow: 0 20px 48px rgba(16, 32, 51, 0.12);
+        }
+        * { box-sizing: border-box; }
+        body {
+            margin: 0;
+            font-family: "Aptos", "Segoe UI", "Microsoft YaHei", sans-serif;
+            color: var(--text);
+            background:
+                radial-gradient(circle at top right, rgba(63, 143, 44, 0.14), transparent 30%),
+                radial-gradient(circle at bottom left, rgba(15, 103, 181, 0.1), transparent 24%),
+                var(--bg);
+        }
+        .page { max-width: 1280px; margin: 0 auto; padding: 24px; }
+        .hero, .card {
+            background: var(--panel);
+            border: 1px solid var(--line);
+            border-radius: 28px;
+            box-shadow: var(--shadow);
+        }
+        .hero { padding: 28px; margin-bottom: 18px; }
+        .eyebrow {
+            display: inline-flex;
+            padding: 7px 12px;
+            border-radius: 999px;
+            background: rgba(63, 143, 44, 0.1);
+            color: var(--brand);
+            font-size: 12px;
+            font-weight: 800;
+            letter-spacing: 0.1em;
+            text-transform: uppercase;
+        }
+        h1, h2, h3 { margin: 10px 0 12px; }
+        p { margin: 0; color: var(--muted); line-height: 1.8; }
+        .actions, .toolbar, .flow, .chips {
+            display: flex;
+            gap: 10px;
+            flex-wrap: wrap;
+        }
+        .btn, .btn-soft {
+            border: 0;
+            border-radius: 999px;
+            padding: 12px 18px;
+            font-weight: 700;
+            cursor: pointer;
+        }
+        .btn { background: linear-gradient(135deg, var(--brand), #62b049); color: #fff; }
+        .btn-soft { background: #eaf3ff; color: var(--accent); }
+        .grid {
+            display: grid;
+            gap: 18px;
+            grid-template-columns: 420px minmax(0, 1fr);
+        }
+        .card { padding: 22px; }
+        .list {
+            display: flex;
+            flex-direction: column;
+            gap: 12px;
+            margin-top: 14px;
+        }
+        .list-item, .flow-step {
+            padding: 14px;
+            border-radius: 18px;
+            border: 1px solid var(--line);
+            background: rgba(255,255,255,0.45);
+        }
+        .flow {
+            display: grid;
+            grid-template-columns: repeat(5, minmax(0, 1fr));
+            margin-top: 14px;
+        }
+        .pill {
+            display: inline-flex;
+            padding: 6px 10px;
+            border-radius: 999px;
+            background: rgba(15, 103, 181, 0.08);
+            color: var(--accent);
+            font-size: 12px;
+            font-weight: 700;
+        }
+        pre {
+            margin: 0;
+            min-height: 280px;
+            padding: 16px;
+            border-radius: 18px;
+            background: #0f1621;
+            color: #deebff;
+            white-space: pre-wrap;
+            font-family: Consolas, "Courier New", monospace;
+            overflow: auto;
+        }
+        @media (max-width: 1060px) {
+            .grid, .flow { grid-template-columns: 1fr; }
+        }
+        @media (max-width: 720px) {
+            .page { padding: 14px; }
+        }
     </style>
 </head>
 <body>
-    <div class="nav">
-        <a href="/">← 返回首页</a>
-        <a href="/users.html">用户管理</a>
-        <a href="/events.html">事件机制</a>
-    </div>
-    
-    <h1>🔪 AOP 切面编程</h1>
-    
-    <div class="card">
-        <h3>📊 实时性能统计</h3>
-        <p>AOP 自动统计所有 Controller 和 Service 方法的执行时间</p>
-        <button class="btn btn-primary" onclick="loadStats()">刷新统计数据</button>
-        <div class="result-box" id="statsResult">点击按钮查看...</div>
-    </div>
-    
-    <h2>📚 AOP 核心概念</h2>
-    
-    <div class="card">
-        <h3>1. 什么是 AOP？</h3>
-        <p>AOP (Aspect-Oriented Programming) 面向切面编程，是将<strong>横切关注点</strong>与<strong>业务逻辑</strong>分离的编程范式。</p>
-        <div class="tip">
-            <strong>横切关注点：</strong>日志、事务、安全、性能监控等，散布在多个模块中的公共功能。
+<div class="page">
+    <section class="hero">
+        <div class="eyebrow">AOP Lab</div>
+        <h1>Make cross-cutting behavior visible instead of abstract.</h1>
+        <p>
+            This page focuses on the parts students usually miss: where advice wraps controller and service methods,
+            how timing is collected, and why a validation failure still counts as observed runtime behavior.
+        </p>
+        <div class="actions" style="margin-top:18px;">
+            <a class="btn-soft" href="/">Back home</a>
+            <a class="btn-soft" href="/users.html">Open user lab</a>
+            <a class="btn-soft" href="/events.html">Open event lab</a>
         </div>
+    </section>
+
+    <div class="grid">
+        <aside class="card">
+            <div class="eyebrow">Experiment Path</div>
+            <h2>Recommended AOP sequence</h2>
+            <div class="list">
+                <div class="list-item">
+                    <strong>1. Trigger controller calls</strong>
+                    <p>Run the list and stats endpoints to make sure both controller and service methods execute.</p>
+                </div>
+                <div class="list-item">
+                    <strong>2. Trigger a validation failure</strong>
+                    <p>Send an invalid user payload and compare the failed request with the successful ones.</p>
+                </div>
+                <div class="list-item">
+                    <strong>3. Inspect aspect output</strong>
+                    <p>Load the stats endpoint and compare call counts, total time, and average time.</p>
+                </div>
+            </div>
+
+            <div class="eyebrow" style="margin-top:18px;">Advice Map</div>
+            <div class="chips" style="margin-top:12px;">
+                <span class="pill">@Before</span>
+                <span class="pill">@After</span>
+                <span class="pill">@AfterReturning</span>
+                <span class="pill">@AfterThrowing</span>
+                <span class="pill">@Around</span>
+            </div>
+
+            <div class="flow">
+                <div class="flow-step"><strong>Before</strong><p>Inspect inputs or auth context.</p></div>
+                <div class="flow-step"><strong>Around</strong><p>Start timer and continue the join point.</p></div>
+                <div class="flow-step"><strong>Controller</strong><p>Delegate work to the service.</p></div>
+                <div class="flow-step"><strong>Service</strong><p>Apply business logic.</p></div>
+                <div class="flow-step"><strong>After*</strong><p>Record result or failure details.</p></div>
+            </div>
+        </aside>
+
+        <main class="card">
+            <div class="eyebrow">Live Runs</div>
+            <h2>Run requests and inspect collected metrics</h2>
+            <p>The buttons below help you create real traffic, then inspect the aspect output without switching tools.</p>
+
+            <div class="toolbar" style="margin-top:14px;">
+                <button class="btn" type="button" onclick="loadUsers()">Load users</button>
+                <button class="btn-soft" type="button" onclick="loadUserStats()">Load user stats</button>
+                <button class="btn-soft" type="button" onclick="sendInvalidUser()">Send invalid user</button>
+                <button class="btn-soft" type="button" onclick="loadAopStats()">Load AOP stats</button>
+            </div>
+
+            <div class="list" style="margin-top:18px;">
+                <div class="list-item">
+                    <strong>What to observe in the console</strong>
+                    <p>Look for controller and service timing lines. Compare success and failure paths to see how around advice still records method duration.</p>
+                </div>
+                <div class="list-item">
+                    <strong>What to inspect in code</strong>
+                    <p>Read <code>PerformanceAspect</code> first, then compare it with the user endpoints that it wraps.</p>
+                </div>
+            </div>
+
+            <pre id="resultBox">Run one of the experiments above to inspect live JSON output.</pre>
+        </main>
     </div>
-    
-    <div class="card">
-        <h3>2. 核心术语</h3>
-        <table>
-            <tr><th>术语</th><th>说明</th></tr>
-            <tr><td><strong>Aspect (切面)</strong></td><td>横切关注点的模块化封装</td></tr>
-            <tr><td><strong>JoinPoint (连接点)</strong></td><td>程序执行的某个点（方法调用、异常抛出等）</td></tr>
-            <tr><td><strong>Pointcut (切入点)</strong></td><td>匹配连接点的表达式</td></tr>
-            <tr><td><strong>Advice (通知)</strong></td><td>在连接点执行的动作</td></tr>
-            <tr><td><strong>Weaving (织入)</strong></td><td>将切面应用到目标对象的过程</td></tr>
-        </table>
-    </div>
-    
-    <div class="card">
-        <h3>3. 五种通知类型</h3>
-        <table>
-            <tr><th>注解</th><th>执行时机</th><th>用途</th></tr>
-            <tr><td><code>@Before</code></td><td>方法执行前</td><td>参数校验、权限检查</td></tr>
-            <tr><td><code>@After</code></td><td>方法执行后（无论成功或异常）</td><td>资源清理</td></tr>
-            <tr><td><code>@AfterReturning</code></td><td>方法成功返回后</td><td>结果处理、日志记录</td></tr>
-            <tr><td><code>@AfterThrowing</code></td><td>方法抛出异常后</td><td>异常处理、错误日志</td></tr>
-            <tr><td><code>@Around</code></td><td>环绕方法执行（最强大）</td><td>性能统计、事务管理</td></tr>
-        </table>
-    </div>
-    
-    <h2>💻 代码示例</h2>
-    
-    <div class="card">
-        <h3>日志切面示例</h3>
-        <pre><code>@Aspect
-@Component
-public class LoggingAspect {
-    
-    // 切入点：匹配所有 Controller 方法
-    @Pointcut("execution(* com.example.demo.controller.*.*(..))")
-    public void controllerMethods() {}
-    
-    // 前置通知
-    @Before("controllerMethods()")
-    public void logBefore(JoinPoint jp) {
-        System.out.println("[AOP-Before] 方法开始: " + jp.getSignature().getName());
-    }
-    
-    // 返回通知
-    @AfterReturning(pointcut = "controllerMethods()", returning = "result")
-    public void logAfterReturning(JoinPoint jp, Object result) {
-        System.out.println("[AOP-AfterReturning] 返回值: " + result);
-    }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>性能监控切面 (@Around)</h3>
-        <pre><code>@Aspect
-@Component
-public class PerformanceAspect {
-    
-    @Around("execution(* com.example.demo..*.*(..))")
-    public Object measureTime(ProceedingJoinPoint pjp) throws Throwable {
-        long start = System.currentTimeMillis();
-        
+</div>
+
+<script>
+    async function renderRequest(path, options = {}) {
+        const box = document.getElementById('resultBox');
+        box.textContent = 'Loading ' + path + ' ...';
         try {
-            Object result = pjp.proceed(); // 执行目标方法
-            long duration = System.currentTimeMillis() - start;
-            System.out.println("[AOP] " + pjp.getSignature() + " 耗时: " + duration + "ms");
-            return result;
-        } catch (Throwable e) {
-            System.out.println("[AOP] 方法异常: " + e.getMessage());
-            throw e;
+            const response = await fetch(path, options);
+            const data = await response.json();
+            box.textContent = JSON.stringify(data, null, 2);
+        } catch (error) {
+            box.textContent = 'Request failed: ' + error.message;
         }
     }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>切入点表达式语法</h3>
-        <pre><code>// 匹配任意公共方法
-execution(public * *(..))
 
-// 匹配 com.example 包下所有方法
-execution(* com.example.*.*(..))
+    async function loadUsers() {
+        await renderRequest('/api/users');
+    }
 
-// 匹配 Controller 层所有方法
-execution(* com.example.demo.controller.*.*(..))
+    async function loadUserStats() {
+        await renderRequest('/api/users/stats');
+    }
 
-// 匹配所有 Service 层的 save 开头的方法
-execution(* com.example.demo.service.*.save*(..))
+    async function loadAopStats() {
+        await renderRequest('/aop/aop/stats');
+    }
 
-// 匹配带有 @Service 注解的类
-@within(org.springframework.stereotype.Service)
-
-// 匹配带有自定义注解的方法
-@annotation(com.example.demo.aop.RateLimited)</code></pre>
-    </div>
-    
-    <h2>🎯 实际应用场景</h2>
-    
-    <div class="card">
-        <table>
-            <tr><th>场景</th><th>实现方式</th></tr>
-            <tr><td>日志记录</td><td>@Before + @AfterReturning</td></tr>
-            <tr><td>性能监控</td><td>@Around</td></tr>
-            <tr><td>事务管理</td><td>@Around (Spring 已内置)</td></tr>
-            <tr><td>权限检查</td><td>@Before</td></tr>
-            <tr><td>限流控制</td><td>@Around + 自定义注解</td></tr>
-            <tr><td>缓存</td><td>@Around (Spring Cache)</td></tr>
-        </table>
-    </div>
-    
-    <p style="margin-top: 30px;"><a href="/">← 返回学习中心</a></p>
-    
-    <script>
-        async function loadStats() {
-            const res = await fetch('/aop/stats');
-            const data = await res.json();
-            document.getElementById('statsResult').textContent = JSON.stringify(data, null, 2);
-        }
-    </script>
+    async function sendInvalidUser() {
+        await renderRequest('/api/users', {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ name: '', email: 'bad', age: 999 })
+        });
+    }
+</script>
 </body>
-</html>
+</html>

src/main/resources/static/events.html

@@ -1,213 +1,245 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="en">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>事件机制 - Spring Boot</title>
+    <title>Spring Event Lab</title>
     <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 900px; margin: 0 auto; padding: 20px; background: #f5f5f5; }
-        h1 { color: #6DB33F; margin: 20px 0; }
-        h2 { color: #333; border-bottom: 2px solid #6DB33F; padding-bottom: 10px; margin: 20px 0 15px; }
-        h3 { color: #6DB33F; margin: 15px 0 10px; }
-        .card { background: white; padding: 25px; margin: 15px 0; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
-        .btn { display: inline-block; padding: 12px 24px; border-radius: 8px; text-decoration: none; font-weight: 500; cursor: pointer; border: none; margin: 5px; }
-        .btn-primary { background: #6DB33F; color: white; }
-        .btn-primary:hover { background: #5da32f; }
-        .btn-info { background: #17a2b8; color: white; }
-        .btn-warning { background: #ffc107; color: #333; }
-        code { background: #f0f0f0; padding: 2px 8px; border-radius: 4px; font-family: 'Fira Code', monospace; }
-        pre { background: #2d2d2d; color: #f8f8f2; padding: 20px; border-radius: 8px; overflow-x: auto; margin: 15px 0; }
-        pre code { background: none; color: inherit; }
-        .tip { background: #e7f3ff; padding: 15px; border-radius: 8px; margin: 15px 0; border-left: 4px solid #6DB33F; }
-        .result-box { background: #2d2d2d; color: #f8f8f2; padding: 15px; border-radius: 8px; font-family: monospace; white-space: pre-wrap; margin-top: 10px; max-height: 300px; overflow-y: auto; }
-        table { width: 100%; border-collapse: collapse; margin: 15px 0; }
-        th, td { border: 1px solid #ddd; padding: 12px; text-align: left; }
-        th { background: #6DB33F; color: white; }
-        .event-flow { display: flex; align-items: center; justify-content: center; margin: 20px 0; }
-        .event-flow span { padding: 15px 25px; background: #6DB33F; color: white; border-radius: 8px; margin: 0 10px; }
-        .event-flow .arrow { font-size: 24px; color: #6DB33F; }
-        .nav { margin-bottom: 20px; }
-        .nav a { margin-right: 15px; color: #6DB33F; text-decoration: none; }
-        .nav a:hover { text-decoration: underline; }
+        :root {
+            --bg: #fff4ea;
+            --panel: rgba(255,255,255,0.95);
+            --line: #eed9c9;
+            --text: #132238;
+            --muted: #6a7484;
+            --brand: #dd6c1f;
+            --accent: #0f67b5;
+            --shadow: 0 22px 52px rgba(18, 32, 51, 0.12);
+        }
+        * { box-sizing: border-box; }
+        body {
+            margin: 0;
+            color: var(--text);
+            font-family: "Aptos", "Segoe UI", "Microsoft YaHei", sans-serif;
+            background:
+                radial-gradient(circle at top right, rgba(221, 108, 31, 0.16), transparent 28%),
+                radial-gradient(circle at bottom left, rgba(15, 103, 181, 0.1), transparent 22%),
+                var(--bg);
+        }
+        .page { max-width: 1280px; margin: 0 auto; padding: 24px; }
+        .hero, .card {
+            background: var(--panel);
+            border: 1px solid var(--line);
+            border-radius: 28px;
+            box-shadow: var(--shadow);
+        }
+        .hero { padding: 28px; margin-bottom: 18px; }
+        .eyebrow {
+            display: inline-flex;
+            padding: 7px 12px;
+            border-radius: 999px;
+            background: rgba(221, 108, 31, 0.1);
+            color: var(--brand);
+            font-size: 12px;
+            font-weight: 800;
+            letter-spacing: 0.1em;
+            text-transform: uppercase;
+        }
+        h1, h2, h3 { margin: 10px 0 12px; }
+        p { margin: 0; color: var(--muted); line-height: 1.8; }
+        .grid {
+            display: grid;
+            gap: 18px;
+            grid-template-columns: 420px minmax(0, 1fr);
+        }
+        .card { padding: 22px; }
+        .list {
+            display: flex;
+            flex-direction: column;
+            gap: 12px;
+            margin-top: 14px;
+        }
+        .item, .timeline-step {
+            padding: 14px;
+            border-radius: 18px;
+            border: 1px solid var(--line);
+            background: rgba(255,255,255,0.46);
+        }
+        .toolbar, .actions {
+            display: flex;
+            gap: 10px;
+            flex-wrap: wrap;
+        }
+        .btn, .btn-soft {
+            border: 0;
+            border-radius: 999px;
+            padding: 12px 18px;
+            font-weight: 700;
+            cursor: pointer;
+        }
+        .btn { background: linear-gradient(135deg, var(--brand), #f39a55); color: #fff; }
+        .btn-soft { background: #edf5ff; color: var(--accent); }
+        .fields {
+            display: grid;
+            gap: 12px;
+            grid-template-columns: repeat(3, minmax(0, 1fr));
+            margin-top: 14px;
+        }
+        label {
+            display: flex;
+            flex-direction: column;
+            gap: 8px;
+            font-size: 13px;
+            font-weight: 700;
+            color: #22394f;
+        }
+        input, select {
+            width: 100%;
+            border: 1px solid var(--line);
+            border-radius: 14px;
+            padding: 12px 14px;
+            background: transparent;
+            color: var(--text);
+            outline: none;
+        }
+        .timeline {
+            display: grid;
+            grid-template-columns: repeat(4, minmax(0, 1fr));
+            gap: 12px;
+            margin-top: 14px;
+        }
+        pre {
+            margin: 0;
+            min-height: 280px;
+            padding: 16px;
+            border-radius: 18px;
+            background: #111926;
+            color: #deebff;
+            white-space: pre-wrap;
+            font-family: Consolas, "Courier New", monospace;
+            overflow: auto;
+        }
+        @media (max-width: 1060px) {
+            .grid, .timeline, .fields { grid-template-columns: 1fr; }
+        }
+        @media (max-width: 720px) {
+            .page { padding: 14px; }
+        }
     </style>
 </head>
 <body>
-    <div class="nav">
-        <a href="/">← 返回首页</a>
-        <a href="/users.html">用户管理</a>
-        <a href="/aop.html">AOP 切面</a>
-    </div>
-    
-    <h1>📡 Spring 事件机制</h1>
-    
-    <div class="card">
-        <h3>🎉 事件发布演示</h3>
-        <p>模拟用户登录事件，观察事件发布和监听过程</p>
-        <div style="margin: 15px 0;">
-            <input type="text" id="userName" placeholder="用户名" value="张三" style="padding: 10px; border: 1px solid #ddd; border-radius: 4px; width: 150px;">
-            <input type="number" id="userId" placeholder="用户ID" value="1" style="padding: 10px; border: 1px solid #ddd; border-radius: 4px; width: 100px;">
-            <button class="btn btn-primary" onclick="publishEvent()">发布登录事件</button>
+<div class="page">
+    <section class="hero">
+        <div class="eyebrow">Event Lab</div>
+        <h1>Understand publisher-listener decoupling through a visible event timeline.</h1>
+        <p>
+            This page helps you observe what usually stays hidden: the request can finish quickly while listeners keep
+            reacting in the background. Publish multiple event types and then inspect the shared event history.
+        </p>
+        <div class="actions" style="margin-top:18px;">
+            <a class="btn-soft" href="/">Back home</a>
+            <a class="btn-soft" href="/aop.html">Open AOP lab</a>
+            <a class="btn-soft" href="/users.html">Open user lab</a>
         </div>
-        <div class="result-box" id="eventResult">等待事件发布...</div>
+    </section>
+
+    <div class="grid">
+        <aside class="card">
+            <div class="eyebrow">Event Story</div>
+            <h2>What to watch for</h2>
+            <div class="timeline">
+                <div class="timeline-step"><strong>Controller</strong><p>Receives the publish request.</p></div>
+                <div class="timeline-step"><strong>Publisher</strong><p>Builds a `UserEvent` and emits it.</p></div>
+                <div class="timeline-step"><strong>Listeners</strong><p>Track history and optional async work.</p></div>
+                <div class="timeline-step"><strong>History API</strong><p>Lets you inspect what actually happened.</p></div>
+            </div>
+
+            <div class="list">
+                <div class="item">
+                    <strong>Experiment 1</strong>
+                    <p>Publish LOGIN twice with different users and confirm the history list grows without changing controller code.</p>
+                </div>
+                <div class="item">
+                    <strong>Experiment 2</strong>
+                    <p>Publish CREATED and then refresh history to see the same endpoint support multiple listener paths.</p>
+                </div>
+                <div class="item">
+                    <strong>Code pairing tip</strong>
+                    <p>Read `UserEventPublisher` and `UserEventListener` side by side to see the decoupling boundary.</p>
+                </div>
+            </div>
+        </aside>
+
+        <main class="card">
+            <div class="eyebrow">Live Event Console</div>
+            <h2>Publish events and inspect history</h2>
+            <p>Use the form to publish events, then reload history to inspect type, user, detail, and timestamp.</p>
+
+            <div class="fields">
+                <label>
+                    Event type
+                    <select id="eventType">
+                        <option value="LOGIN">LOGIN</option>
+                        <option value="CREATED">CREATED</option>
+                        <option value="UPDATED">UPDATED</option>
+                        <option value="DELETED">DELETED</option>
+                    </select>
+                </label>
+                <label>
+                    User id
+                    <input id="userId" value="21">
+                </label>
+                <label>
+                    User name
+                    <input id="userName" value="observer-demo">
+                </label>
+            </div>
+
+            <div class="toolbar" style="margin-top:14px;">
+                <button class="btn" type="button" onclick="publishEvent()">Publish event</button>
+                <button class="btn-soft" type="button" onclick="loadHistory()">Load history</button>
+                <button class="btn-soft" type="button" onclick="loadInfo()">Load event notes</button>
+            </div>
+
+            <div class="list" style="margin-top:18px;">
+                <div class="item">
+                    <strong>Interpretation hint</strong>
+                    <p>If the controller returns immediately but history keeps growing, you are seeing decoupled follow-up behavior in action.</p>
+                </div>
+            </div>
+
+            <pre id="resultBox">Publish an event or load history to inspect live output.</pre>
+        </main>
     </div>
-    
-    <h2>🔄 事件机制流程</h2>
-    
-    <div class="event-flow">
-        <span>发布者</span>
-        <span class="arrow">→</span>
-        <span>ApplicationEventPublisher</span>
-        <span class="arrow">→</span>
-        <span>事件</span>
-        <span class="arrow">→</span>
-        <span>监听者</span>
-    </div>
-    
-    <div class="tip">
-        <strong>核心优势：</strong>
-        <ul style="margin-top: 10px; padding-left: 20px;">
-            <li><strong>解耦：</strong>发布者和监听者互不依赖</li>
-            <li><strong>扩展：</strong>新增监听器无需修改发布者</li>
-            <li><strong>异步：</strong>耗时操作不阻塞主流程</li>
-        </ul>
-    </div>
-    
-    <h2>💻 代码实现</h2>
-    
-    <div class="card">
-        <h3>1. 定义事件</h3>
-        <pre><code>public class UserEvent {
-    public enum Type { CREATED, UPDATED, DELETED, LOGIN }
-    
-    private Type type;
-    private Long userId;
-    private String userName;
-    private LocalDateTime timestamp;
-    
-    // constructor, getters...
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>2. 发布事件</h3>
-        <pre><code>@Component
-public class UserEventPublisher {
-    
-    @Autowired
-    private ApplicationEventPublisher eventPublisher;
-    
-    public void publishUserLogin(Long userId, String userName) {
-        UserEvent event = new UserEvent(
-            UserEvent.Type.LOGIN,
-            userId,
-            userName,
-            "用户登录成功"
-        );
-        eventPublisher.publishEvent(event);
-    }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>3. 监听事件</h3>
-        <pre><code>@Component
-public class UserEventListener {
-    
-    // 基础监听
-    @EventListener
-    public void handleUserEvent(UserEvent event) {
-        System.out.println("收到事件: " + event.getType());
-    }
-    
-    // 条件监听 - 只处理登录事件
-    @EventListener(condition = "#event.type == T(com.example.demo.model.UserEvent$Type).LOGIN")
-    public void handleLogin(UserEvent event) {
-        System.out.println("用户登录: " + event.getUserName());
-    }
-    
-    // 异步监听 - 不阻塞主流程
-    @Async
-    @EventListener
-    public void sendWelcomeEmail(UserEvent event) {
-        // 发送邮件...
-    }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>4. 控制器中使用</h3>
-        <pre><code>@RestController
-@RequestMapping("/aop")
-public class AopEventController {
-    
-    @Autowired
-    private UserEventPublisher eventPublisher;
-    
-    @PostMapping("/event/publish")
-    public Map&lt;String, Object&gt; publishEvent(
-            @RequestParam Long userId,
-            @RequestParam String userName) {
-        
-        // 发布事件
-        eventPublisher.publishUserLogin(userId, userName);
-        
-        return Map.of(
-            "message", "事件已发布",
-            "userId", userId,
-            "userName", userName
-        );
-    }
-}</code></pre>
-    </div>
-    
-    <h2>🎯 应用场景</h2>
-    
-    <div class="card">
-        <table>
-            <tr><th>场景</th><th>事件类型</th><th>处理逻辑</th></tr>
-            <tr><td>用户注册</td><td>UserCreatedEvent</td><td>发送欢迎邮件、初始化数据</td></tr>
-            <tr><td>订单创建</td><td>OrderCreatedEvent</td><td>扣库存、发送通知</td></tr>
-            <tr><td>支付成功</td><td>PaymentSuccessEvent</td><td>更新订单状态、发送短信</td></tr>
-            <tr><td>用户登录</td><td>UserLoginEvent</td><td>记录登录日志、更新在线状态</td></tr>
-        </table>
-    </div>
-    
-    <div class="card">
-        <h3>💡 最佳实践</h3>
-        <ul style="line-height: 2; padding-left: 20px;">
-            <li>事件类应该是<strong>不可变</strong>的（只读属性）</li>
-            <li>使用 <code>@Async</code> 处理耗时操作</li>
-            <li>避免在监听器中抛出异常</li>
-            <li>使用 <code>condition</code> 过滤不需要的事件</li>
-            <li>复杂场景考虑使用消息队列（RabbitMQ/Kafka）</li>
-        </ul>
-    </div>
-    
-    <p style="margin-top: 30px;"><a href="/">← 返回学习中心</a></p>
-    
-    <script>
-        async function publishEvent() {
-            const userId = document.getElementById('userId').value;
-            const userName = document.getElementById('userName').value;
-            
-            try {
-                const res = await fetch(`/aop/event/publish?userId=${userId}&userName=${encodeURIComponent(userName)}`, {
-                    method: 'POST'
-                });
-                const data = await res.json();
-                
-                const resultBox = document.getElementById('eventResult');
-                resultBox.textContent = `[${new Date().toLocaleTimeString()}] 事件已发布\n\n` + 
-                    JSON.stringify(data, null, 2) + '\n\n' +
-                    '📊 查看控制台日志可以看到监听器的输出：\n' +
-                    '[EventPublisher] 发布事件: LOGIN - ' + userName + '\n' +
-                    '[EventListener] 收到事件: LOGIN - 用户: ' + userName + '\n' +
-                    '[LoginTracker] 记录用户登录: ' + userName;
-            } catch (e) {
-                document.getElementById('eventResult').textContent = '错误: ' + e.message;
-            }
+</div>
+
+<script>
+    async function renderRequest(path, options = {}) {
+        const box = document.getElementById('resultBox');
+        box.textContent = 'Loading ' + path + ' ...';
+        try {
+            const response = await fetch(path, options);
+            const data = await response.json();
+            box.textContent = JSON.stringify(data, null, 2);
+        } catch (error) {
+            box.textContent = 'Request failed: ' + error.message;
         }
-    </script>
+    }
+
+    async function publishEvent() {
+        const type = document.getElementById('eventType').value;
+        const userId = document.getElementById('userId').value.trim() || '21';
+        const userName = document.getElementById('userName').value.trim() || 'observer-demo';
+        const params = new URLSearchParams({ userId, userName, eventType: type });
+        await renderRequest('/aop/event/publish?' + params.toString(), { method: 'POST' });
+    }
+
+    async function loadHistory() {
+        await renderRequest('/aop/event/history');
+    }
+
+    async function loadInfo() {
+        await renderRequest('/aop/event');
+    }
+</script>
 </body>
-</html>
+</html>

src/main/resources/static/index.html

@@ -1,221 +1,408 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="en">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>Spring Boot 学习中心</title>
+    <title>Spring Boot Learning Cockpit</title>
     <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 900px; margin: 0 auto; padding: 20px; background: #f5f5f5; }
-        h1 { color: #6DB33F; text-align: center; margin: 30px 0; font-size: 2.5em; }
-        h2 { color: #333; border-bottom: 3px solid #6DB33F; padding-bottom: 10px; margin: 20px 0 15px; }
-        .card { background: white; padding: 25px; margin: 15px 0; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.1); }
-        .card h3 { color: #6DB33F; margin-bottom: 15px; font-size: 1.3em; }
-        .btn-group { display: flex; flex-wrap: wrap; gap: 10px; margin: 15px 0; }
-        .btn { display: inline-block; padding: 12px 24px; border-radius: 8px; text-decoration: none; font-weight: 500; transition: all 0.3s; }
-        .btn-primary { background: #6DB33F; color: white; }
-        .btn-primary:hover { background: #5da32f; transform: translateY(-2px); }
-        .btn-secondary { background: #333; color: white; }
-        .btn-secondary:hover { background: #444; }
-        .btn-info { background: #17a2b8; color: white; }
-        .btn-info:hover { background: #138496; }
-        .btn-warning { background: #ffc107; color: #333; }
-        .btn-warning:hover { background: #e0a800; }
-        code { background: #f0f0f0; padding: 2px 8px; border-radius: 4px; font-family: 'Fira Code', monospace; font-size: 14px; }
-        pre { background: #2d2d2d; color: #f8f8f2; padding: 20px; border-radius: 8px; overflow-x: auto; margin: 15px 0; }
-        pre code { background: none; color: inherit; }
-        ul { line-height: 2; padding-left: 20px; }
-        .feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 15px; }
-        .feature-item { background: #f8f9fa; padding: 20px; border-radius: 8px; border-left: 4px solid #6DB33F; transition: all 0.3s; }
-        .feature-item:hover { transform: translateY(-3px); box-shadow: 0 4px 12px rgba(0,0,0,0.1); }
-        .feature-item h4 { color: #333; margin-bottom: 8px; font-size: 1.1em; }
-        .feature-item p { color: #666; font-size: 14px; margin: 0; }
-        .feature-item a { color: inherit; text-decoration: none; }
-        .api-test { background: #f8f9fa; padding: 15px; margin: 10px 0; border-radius: 8px; }
-        .api-test input, .api-test select { padding: 10px; border: 1px solid #ddd; border-radius: 4px; margin: 5px; }
-        .api-test button { padding: 10px 20px; background: #6DB33F; color: white; border: none; border-radius: 4px; cursor: pointer; }
-        .api-test button:hover { background: #5da32f; }
-        #result { background: #2d2d2d; color: #f8f8f2; padding: 15px; border-radius: 8px; margin-top: 10px; white-space: pre-wrap; font-family: monospace; font-size: 14px; }
-        .footer { text-align: center; margin-top: 40px; padding: 20px; color: #666; border-top: 1px solid #ddd; }
-        .nav-links { display: flex; justify-content: center; gap: 15px; margin-bottom: 30px; }
-        .nav-links a { padding: 10px 20px; background: white; border-radius: 8px; text-decoration: none; color: #6DB33F; font-weight: 500; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
-        .nav-links a:hover { background: #6DB33F; color: white; }
-        .nav-links a.active { background: #6DB33F; color: white; }
+        :root {
+            --bg: #eef5ff;
+            --panel: rgba(255, 255, 255, 0.94);
+            --line: #d8e4f0;
+            --text: #122033;
+            --muted: #5d7288;
+            --brand: #177245;
+            --accent: #0f67b5;
+            --warm: #f08c2b;
+            --shadow: 0 22px 54px rgba(18, 32, 51, 0.12);
+        }
+
+        * { box-sizing: border-box; }
+        body {
+            margin: 0;
+            color: var(--text);
+            font-family: "Aptos", "Segoe UI", "Microsoft YaHei", sans-serif;
+            background:
+                radial-gradient(circle at top left, rgba(23, 114, 69, 0.14), transparent 28%),
+                radial-gradient(circle at bottom right, rgba(15, 103, 181, 0.14), transparent 26%),
+                var(--bg);
+        }
+        a { color: inherit; text-decoration: none; }
+        button, input, select { font: inherit; }
+        .page { max-width: 1380px; margin: 0 auto; padding: 24px; }
+        .hero, .card {
+            background: var(--panel);
+            border: 1px solid var(--line);
+            border-radius: 28px;
+            box-shadow: var(--shadow);
+            backdrop-filter: blur(10px);
+        }
+        .hero { padding: 28px; margin-bottom: 18px; }
+        .eyebrow {
+            display: inline-flex;
+            padding: 7px 12px;
+            border-radius: 999px;
+            background: rgba(23, 114, 69, 0.1);
+            color: var(--brand);
+            font-size: 12px;
+            font-weight: 800;
+            letter-spacing: 0.1em;
+            text-transform: uppercase;
+        }
+        h1, h2, h3 { margin: 10px 0 12px; }
+        p { margin: 0; color: var(--muted); line-height: 1.8; }
+        .hero-grid, .workspace, .triple {
+            display: grid;
+            gap: 18px;
+        }
+        .hero-grid {
+            grid-template-columns: 1.3fr 0.9fr;
+            align-items: start;
+        }
+        .actions, .chip-list, .toolbar, .demo-links {
+            display: flex;
+            gap: 10px;
+            flex-wrap: wrap;
+        }
+        .btn, .btn-soft {
+            display: inline-flex;
+            align-items: center;
+            justify-content: center;
+            border: 0;
+            border-radius: 999px;
+            padding: 12px 18px;
+            cursor: pointer;
+            font-weight: 700;
+        }
+        .btn {
+            color: #fff;
+            background: linear-gradient(135deg, var(--brand), #35a465);
+        }
+        .btn-soft {
+            color: var(--accent);
+            background: #eaf3ff;
+        }
+        .card { padding: 22px; }
+        .stats {
+            display: grid;
+            grid-template-columns: repeat(4, minmax(0, 1fr));
+            gap: 12px;
+            margin-top: 18px;
+        }
+        .stat {
+            padding: 16px;
+            border-radius: 18px;
+            border: 1px solid var(--line);
+            background: rgba(255,255,255,0.5);
+        }
+        .stat span { display: block; color: var(--muted); font-size: 12px; margin-bottom: 8px; }
+        .stat strong { font-size: 28px; }
+        .workspace {
+            grid-template-columns: 380px minmax(0, 1fr);
+            align-items: start;
+        }
+        .triple {
+            grid-template-columns: repeat(3, minmax(0, 1fr));
+        }
+        .flow {
+            display: grid;
+            grid-template-columns: repeat(6, minmax(0, 1fr));
+            gap: 12px;
+            margin-top: 14px;
+        }
+        .step, .lab, .note, .code-card {
+            border: 1px solid var(--line);
+            border-radius: 20px;
+            padding: 16px;
+            background: rgba(255,255,255,0.45);
+        }
+        .step strong, .lab strong, .code-card strong { display: block; margin-bottom: 8px; }
+        .lab small, .step small, .note small { color: var(--muted); display: block; line-height: 1.7; }
+        .field {
+            display: flex;
+            flex-direction: column;
+            gap: 8px;
+            margin-top: 12px;
+        }
+        label { font-size: 13px; font-weight: 700; color: #21384f; }
+        input, select {
+            width: 100%;
+            border: 1px solid var(--line);
+            border-radius: 14px;
+            padding: 12px 14px;
+            background: transparent;
+            color: var(--text);
+            outline: none;
+        }
+        .console {
+            margin-top: 14px;
+            border-radius: 18px;
+            overflow: hidden;
+            border: 1px solid #d6e2ef;
+            background: #0e1723;
+        }
+        .console-head {
+            padding: 12px 14px;
+            border-bottom: 1px solid rgba(216, 228, 240, 0.14);
+            color: #bdd2ea;
+            font-weight: 700;
+        }
+        pre {
+            margin: 0;
+            min-height: 240px;
+            padding: 16px;
+            color: #dceaff;
+            white-space: pre-wrap;
+            font-family: Consolas, "Courier New", monospace;
+            overflow: auto;
+        }
+        .pill {
+            display: inline-flex;
+            padding: 6px 10px;
+            border-radius: 999px;
+            background: rgba(15, 103, 181, 0.08);
+            color: var(--accent);
+            font-size: 12px;
+            font-weight: 700;
+        }
+        .list {
+            display: flex;
+            flex-direction: column;
+            gap: 10px;
+            margin-top: 14px;
+        }
+        .list-item {
+            padding: 14px;
+            border-radius: 18px;
+            border: 1px solid var(--line);
+            background: rgba(255,255,255,0.45);
+        }
+        .list-item p { margin-top: 8px; }
+        @media (max-width: 1180px) {
+            .hero-grid, .workspace, .triple, .flow, .stats { grid-template-columns: 1fr 1fr; }
+        }
+        @media (max-width: 780px) {
+            .page { padding: 14px; }
+            .hero-grid, .workspace, .triple, .flow, .stats { grid-template-columns: 1fr; }
+        }
     </style>
 </head>
 <body>
-    <h1>🍃 Spring Boot 学习中心</h1>
-    
-    <div class="nav-links">
-        <a href="/" class="active">首页</a>
-        <a href="/users.html">用户管理</a>
-        <a href="/aop.html">AOP 切面</a>
-        <a href="/events.html">事件机制</a>
-    </div>
-    
-    <div class="card">
-        <h3>📚 学习模块</h3>
-        <div class="feature-grid">
-            <a href="/users.html" class="feature-item">
-                <h4>👥 用户管理</h4>
-                <p>RESTful API 设计、CRUD 操作、参数绑定</p>
-            </a>
-            <a href="/aop.html" class="feature-item">
-                <h4>🔪 AOP 切面编程</h4>
-                <p>日志记录、性能监控、限流控制</p>
-            </a>
-            <a href="/events.html" class="feature-item">
-                <h4>📡 事件机制</h4>
-                <p>发布/订阅模式、解耦业务逻辑</p>
-            </a>
+<div class="page">
+    <section class="hero">
+        <div class="hero-grid">
+            <div>
+                <div class="eyebrow">Spring Boot Learning Cockpit</div>
+                <h1>Use one workspace to understand MVC, validation, security, AOP, and application events.</h1>
+                <p>
+                    This homepage is now a guided study cockpit. Instead of only linking to pages, it explains the request
+                    path, suggests experiment sequences, and lets you call real endpoints to observe how the demo behaves.
+                </p>
+                <div class="actions" style="margin-top:18px;">
+                    <a class="btn" href="/users.html">Open user lab</a>
+                    <a class="btn-soft" href="/aop.html">Open AOP lab</a>
+                    <a class="btn-soft" href="/events.html">Open event lab</a>
+                    <a class="btn-soft" href="/learn">Open MVC learn API</a>
+                </div>
+                <div class="stats">
+                    <div class="stat"><span>Core labs</span><strong>4</strong></div>
+                    <div class="stat"><span>Major layers</span><strong>6</strong></div>
+                    <div class="stat"><span>Interactive pages</span><strong>4</strong></div>
+                    <div class="stat"><span>Tested backend paths</span><strong>2+</strong></div>
+                </div>
+            </div>
+            <div class="card" style="padding:0;">
+                <div class="card" style="box-shadow:none; border:none; border-radius:28px;">
+                    <div class="eyebrow">Start Here</div>
+                    <h2>Recommended study order</h2>
+                    <div class="list">
+                        <div class="list-item">
+                            <strong>1. Learn endpoint binding</strong>
+                            <p>Hit the live API explorer below and compare query, path, header, cookie, and JSON body patterns.</p>
+                        </div>
+                        <div class="list-item">
+                            <strong>2. Study users and validation</strong>
+                            <p>Open the user lab to inspect CRUD, duplicate email handling, and aggregate stats.</p>
+                        </div>
+                        <div class="list-item">
+                            <strong>3. Watch cross-cutting behavior</strong>
+                            <p>Move to AOP and events to see timing, rate limiting, and listener history.</p>
+                        </div>
+                    </div>
+                </div>
+            </div>
         </div>
-    </div>
-    
-    <h2>🔗 快速链接</h2>
-    <div class="card">
-        <div class="btn-group">
-            <a class="btn btn-primary" href="/learn">API 接口列表</a>
-            <a class="btn btn-info" href="/api/users">用户 JSON</a>
-            <a class="btn btn-secondary" href="/actuator/health">健康检查</a>
-        </div>
-    </div>
-    
-    <h2>🧪 接口测试</h2>
-    
-    <div class="card">
-        <h3>GET 参数示例</h3>
-        <div class="api-test">
-            <input type="text" id="param-name" placeholder="姓名" value="张三">
-            <input type="number" id="param-age" placeholder="年龄" value="25">
-            <button onclick="testParams()">测试</button>
-            <div id="result-params"></div>
-        </div>
-        <p><code>GET /learn/params?name=xxx&age=18</code></p>
-    </div>
-    
-    <div class="card">
-        <h3>路径变量示例</h3>
-        <div class="api-test">
-            <input type="text" id="path-id" placeholder="ID" value="123">
-            <button onclick="testPath()">测试</button>
-            <div id="result-path"></div>
-        </div>
-        <p><code>GET /learn/path/{id}</code></p>
-    </div>
-    
-    <div class="card">
-        <h3>POST JSON 示例</h3>
-        <div class="api-test">
-            <input type="text" id="post-data" placeholder='JSON 数据' value='{"name":"test","value":123}' style="width: 300px;">
-            <button onclick="testPost()">测试</button>
-            <div id="result-post"></div>
-        </div>
-        <p><code>POST /learn/body</code></p>
-    </div>
-    
-    <h2>📖 学习路径</h2>
-    
-    <div class="card">
-        <h3>1. IOC 容器</h3>
-        <ul>
-            <li><code>@Component</code>, <code>@Service</code>, <code>@Repository</code>, <code>@Controller</code></li>
-            <li><code>@Autowired</code> 依赖注入</li>
-            <li><code>@Configuration</code> + <code>@Bean</code> 配置类</li>
-        </ul>
-    </div>
-    
-    <div class="card">
-        <h3>2. Web 开发</h3>
-        <ul>
-            <li><code>@RestController</code> = <code>@Controller</code> + <code>@ResponseBody</code></li>
-            <li><code>@RequestMapping</code>, <code>@GetMapping</code>, <code>@PostMapping</code></li>
-            <li><code>@PathVariable</code>, <code>@RequestParam</code>, <code>@RequestBody</code></li>
-        </ul>
-    </div>
-    
-    <div class="card">
-        <h3>3. AOP 切面编程</h3>
-        <pre><code>@Aspect
-@Component
-public class LoggingAspect {
-    @Before("execution(* com.example.*.*(..))")
-    public void logBefore(JoinPoint jp) {
-        System.out.println("方法调用: " + jp.getSignature());
-    }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h3>4. 事件机制</h3>
-        <pre><code>// 发布事件
-@Autowired
-ApplicationEventPublisher publisher;
-publisher.publishEvent(new UserEvent(...));
+    </section>
 
-// 监听事件
-@EventListener
-public void onEvent(UserEvent event) {
-    // 处理事件
-}</code></pre>
+    <section class="card" style="margin-bottom:18px;">
+        <div class="eyebrow">Architecture</div>
+        <h2>How one request travels through the demo</h2>
+        <div class="flow">
+            <div class="step"><strong>Browser</strong><small>Form submit or fetch call starts the request.</small></div>
+            <div class="step"><strong>Security</strong><small>JWT demo routes decide whether the request is public or protected.</small></div>
+            <div class="step"><strong>Controller</strong><small>Spring binds params, body, headers, and cookies into method arguments.</small></div>
+            <div class="step"><strong>Service</strong><small>Business rules run, such as duplicate email checks or stats calculation.</small></div>
+            <div class="step"><strong>AOP / Events</strong><small>Cross-cutting timing or event listeners react without cluttering core logic.</small></div>
+            <div class="step"><strong>Response</strong><small>Structured JSON or HTML returns to the page and becomes visible feedback.</small></div>
+        </div>
+    </section>
+
+    <div class="workspace">
+        <aside class="card">
+            <div class="eyebrow">Lab Tracks</div>
+            <h2>What to practice in each area</h2>
+            <div class="list">
+                <div class="lab">
+                    <strong>User management</strong>
+                    <small>Create a user, trigger duplicate email protection, search records, and compare stats before and after changes.</small>
+                </div>
+                <div class="lab">
+                    <strong>MVC parameter binding</strong>
+                    <small>Use `/learn` routes to compare `@RequestParam`, `@PathVariable`, `@RequestBody`, `@RequestHeader`, and `@CookieValue`.</small>
+                </div>
+                <div class="lab">
+                    <strong>AOP tracing</strong>
+                    <small>Trigger `/api/users` and `/api/users/stats`, then inspect `/aop/aop/stats` to see which methods were counted.</small>
+                </div>
+                <div class="lab">
+                    <strong>Application events</strong>
+                    <small>Publish LOGIN or CREATED events and refresh event history to understand publisher-listener decoupling.</small>
+                </div>
+            </div>
+
+            <div class="eyebrow" style="margin-top:20px;">Code Reading Map</div>
+            <h2>Files worth reading next</h2>
+            <div class="list">
+                <div class="code-card">
+                    <strong>UserController -> UserService</strong>
+                    <small>Shows validation, CRUD orchestration, search, and stats aggregation.</small>
+                </div>
+                <div class="code-card">
+                    <strong>LearningSecurityConfig + LearningJwtFilter</strong>
+                    <small>Explains why most labs stay public while `/api/secure/**` stays protected.</small>
+                </div>
+                <div class="code-card">
+                    <strong>PerformanceAspect + UserEventPublisher + UserEventListener</strong>
+                    <small>Shows the two cleanest examples of cross-cutting and event-driven behavior.</small>
+                </div>
+            </div>
+        </aside>
+
+        <main class="triple">
+            <section class="card" style="grid-column: 1 / -1;">
+                <div class="eyebrow">Live Explorer</div>
+                <h2>Call real endpoints without leaving the page</h2>
+                <p>Use these controls to inspect real JSON responses while you read the code. This makes the project easier to connect to concrete behavior.</p>
+
+                <div class="toolbar" style="margin-top:14px;">
+                    <button class="btn" type="button" onclick="loadEndpoint('/actuator/health')">Health</button>
+                    <button class="btn-soft" type="button" onclick="loadEndpoint('/api/users/stats')">User stats</button>
+                    <button class="btn-soft" type="button" onclick="loadEndpoint('/learn')">Learn overview</button>
+                    <button class="btn-soft" type="button" onclick="loadEndpoint('/aop/aop/stats')">AOP stats</button>
+                    <button class="btn-soft" type="button" onclick="loadEndpoint('/aop/event/history')">Event history</button>
+                </div>
+
+                <div class="triple" style="margin-top:16px;">
+                    <div class="card" style="padding:0; box-shadow:none; background:transparent; border:none;">
+                        <div class="field">
+                            <label for="eventType">Publish demo event</label>
+                            <select id="eventType">
+                                <option value="LOGIN">LOGIN</option>
+                                <option value="CREATED">CREATED</option>
+                                <option value="UPDATED">UPDATED</option>
+                                <option value="DELETED">DELETED</option>
+                            </select>
+                        </div>
+                    </div>
+                    <div class="card" style="padding:0; box-shadow:none; background:transparent; border:none;">
+                        <div class="field">
+                            <label for="eventUserId">User id</label>
+                            <input id="eventUserId" value="99">
+                        </div>
+                    </div>
+                    <div class="card" style="padding:0; box-shadow:none; background:transparent; border:none;">
+                        <div class="field">
+                            <label for="eventUserName">User name</label>
+                            <input id="eventUserName" value="learning-user">
+                        </div>
+                    </div>
+                </div>
+                <div class="toolbar" style="margin-top:14px;">
+                    <button class="btn" type="button" onclick="publishEvent()">Publish event</button>
+                    <button class="btn-soft" type="button" onclick="loadEndpoint('/api/users')">Load users</button>
+                </div>
+
+                <div class="console">
+                    <div class="console-head">Endpoint output</div>
+                    <pre id="consoleOutput">Select an experiment above to load live output.</pre>
+                </div>
+            </section>
+
+            <section class="card">
+                <div class="eyebrow">Experiment 1</div>
+                <h2>Trace validation</h2>
+                <p>Open the user lab, create a user, then repeat with the same email. Compare the frontend error with `DuplicateEmailException` and the global exception handler.</p>
+                <div class="chip-list" style="margin-top:12px;">
+                    <span class="pill">UserController</span>
+                    <span class="pill">UserService</span>
+                    <span class="pill">GlobalExceptionHandler</span>
+                </div>
+            </section>
+
+            <section class="card">
+                <div class="eyebrow">Experiment 2</div>
+                <h2>Trace AOP timing</h2>
+                <p>Load users and stats several times, then call `/aop/aop/stats`. Watch how controller and service methods accumulate timing and call count data.</p>
+                <div class="chip-list" style="margin-top:12px;">
+                    <span class="pill">PerformanceAspect</span>
+                    <span class="pill">@Around</span>
+                    <span class="pill">Cross-cutting</span>
+                </div>
+            </section>
+
+            <section class="card">
+                <div class="eyebrow">Experiment 3</div>
+                <h2>Trace event decoupling</h2>
+                <p>Publish CREATED and LOGIN events, then reload event history. This shows how the request can finish while listeners keep handling side effects.</p>
+                <div class="chip-list" style="margin-top:12px;">
+                    <span class="pill">Publisher</span>
+                    <span class="pill">Listener</span>
+                    <span class="pill">@Async</span>
+                </div>
+            </section>
+        </main>
     </div>
-    
-    <h2>📁 项目结构</h2>
-    <div class="card">
-        <pre><code>├── src/main/java/com/example/demo/
-│   ├── DemoApplication.java       # 启动类
-│   ├── controller/                # 控制器层
-│   │   ├── LearnController.java   # 学习示例
-│   │   ├── UserController.java    # 用户 API
-│   │   └── AopEventController.java
-│   ├── service/                   # 业务逻辑层
-│   ├── model/                     # 实体类
-│   ├── aop/                       # AOP 切面
-│   │   ├── LoggingAspect.java
-│   │   ├── PerformanceAspect.java
-│   │   └── RateLimitAspect.java
-│   └── event/                     # 事件机制
-│       ├── UserEventPublisher.java
-│       └── UserEventListener.java
-├── src/main/resources/
-│   ├── static/                    # 静态资源
-│   │   ├── index.html
-│   │   ├── users.html
-│   │   ├── aop.html
-│   │   └── events.html
-│   └── application.properties     # 配置文件
-└── pom.xml                        # Maven 配置</code></pre>
-    </div>
-    
-    <div class="footer">
-        <p>🍃 Spring Boot 学习脚手架 | <a href="https://spring.io" style="color: #6DB33F;">Spring 官网</a></p>
-    </div>
-    
-    <script>
-        async function testParams() {
-            const name = document.getElementById('param-name').value;
-            const age = document.getElementById('param-age').value;
-            const res = await fetch(`/learn/params?name=${encodeURIComponent(name)}&age=${age}`);
-            const data = await res.json();
-            document.getElementById('result-params').innerHTML = '<div id="result">' + JSON.stringify(data, null, 2) + '</div>';
+</div>
+
+<script>
+    async function loadEndpoint(path, options = {}) {
+        const output = document.getElementById('consoleOutput');
+        output.textContent = 'Loading ' + path + ' ...';
+        try {
+            const response = await fetch(path, options);
+            const contentType = response.headers.get('content-type') || '';
+            if (contentType.includes('application/json')) {
+                const json = await response.json();
+                output.textContent = JSON.stringify(json, null, 2);
+            } else {
+                output.textContent = await response.text();
+            }
+        } catch (error) {
+            output.textContent = 'Request failed: ' + error.message;
         }
-        
-        async function testPath() {
-            const id = document.getElementById('path-id').value;
-            const res = await fetch(`/learn/path/${id}`);
-            const data = await res.json();
-            document.getElementById('result-path').innerHTML = '<div id="result">' + JSON.stringify(data, null, 2) + '</div>';
-        }
-        
-        async function testPost() {
-            const data = document.getElementById('post-data').value;
-            const res = await fetch('/learn/body', {
-                method: 'POST',
-                headers: { 'Content-Type': 'application/json' },
-                body: data
-            });
-            const result = await res.json();
-            document.getElementById('result-post').innerHTML = '<div id="result">' + JSON.stringify(result, null, 2) + '</div>';
-        }
-    </script>
+    }
+
+    async function publishEvent() {
+        const type = document.getElementById('eventType').value;
+        const userId = document.getElementById('eventUserId').value.trim() || '99';
+        const userName = document.getElementById('eventUserName').value.trim() || 'learning-user';
+        const params = new URLSearchParams({
+            userId,
+            userName,
+            eventType: type
+        });
+        await loadEndpoint('/aop/event/publish?' + params.toString(), { method: 'POST' });
+    }
+</script>
 </body>
-</html>
+</html>

src/main/resources/static/users.html

@@ -1,225 +1,466 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="en">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>用户管理 - Spring Boot</title>
+    <title>User Management Lab</title>
     <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 900px; margin: 0 auto; padding: 20px; background: #f5f5f5; }
-        h1 { color: #6DB33F; margin: 20px 0; }
-        h2 { color: #333; margin: 20px 0 10px; }
-        .card { background: white; padding: 20px; margin: 15px 0; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
-        table { width: 100%; border-collapse: collapse; margin: 15px 0; }
-        th, td { border: 1px solid #ddd; padding: 12px; text-align: left; }
-        th { background: #6DB33F; color: white; }
-        tr:nth-child(even) { background: #f9f9f9; }
-        tr:hover { background: #f0f0f0; }
-        .btn { display: inline-block; padding: 8px 16px; border-radius: 4px; text-decoration: none; font-size: 14px; cursor: pointer; border: none; }
-        .btn-primary { background: #6DB33F; color: white; }
-        .btn-primary:hover { background: #5da32f; }
-        .btn-danger { background: #dc3545; color: white; }
-        .btn-danger:hover { background: #c82333; }
-        .btn-secondary { background: #6c757d; color: white; }
-        .btn-success { background: #28a745; color: white; }
-        .form-group { margin: 15px 0; }
-        .form-group label { display: block; margin-bottom: 5px; font-weight: bold; }
-        .form-group input { width: 100%; padding: 10px; border: 1px solid #ddd; border-radius: 4px; font-size: 14px; }
-        .modal { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.5); }
-        .modal.active { display: flex; justify-content: center; align-items: center; }
-        .modal-content { background: white; padding: 30px; border-radius: 8px; width: 400px; }
-        .modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
-        .modal-header h3 { margin: 0; }
-        .close-btn { background: none; border: none; font-size: 24px; cursor: pointer; }
-        .btn-group { display: flex; gap: 10px; margin-top: 20px; }
-        .tip { background: #e7f3ff; padding: 15px; border-radius: 4px; margin: 15px 0; border-left: 4px solid #6DB33F; }
-        code { background: #f0f0f0; padding: 2px 6px; border-radius: 3px; }
-        pre { background: #2d2d2d; color: #f8f8f2; padding: 15px; border-radius: 4px; overflow-x: auto; }
+        :root {
+            --bg: linear-gradient(135deg, #f4fff2 0%, #eef6ff 100%);
+            --card: rgba(255, 255, 255, 0.94);
+            --line: #dde7f3;
+            --text: #123;
+            --muted: #5c7289;
+            --green: #3f8f2c;
+            --blue: #0f6db5;
+            --red: #d64545;
+            --shadow: 0 18px 45px rgba(17, 47, 80, 0.12);
+        }
+
+        * { box-sizing: border-box; }
+        body {
+            margin: 0;
+            font-family: "Segoe UI", "PingFang SC", sans-serif;
+            background: var(--bg);
+            color: var(--text);
+        }
+        .page {
+            max-width: 1120px;
+            margin: 0 auto;
+            padding: 28px 18px 48px;
+        }
+        .card {
+            background: var(--card);
+            border: 1px solid rgba(255,255,255,0.8);
+            border-radius: 24px;
+            box-shadow: var(--shadow);
+            backdrop-filter: blur(12px);
+        }
+        .hero {
+            display: grid;
+            gap: 18px;
+            grid-template-columns: minmax(0, 1.6fr) minmax(280px, 0.9fr);
+            margin-bottom: 22px;
+        }
+        .hero-main,
+        .hero-side,
+        .table-card,
+        .tool-card {
+            padding: 24px;
+        }
+        .eyebrow {
+            display: inline-flex;
+            padding: 8px 14px;
+            border-radius: 999px;
+            background: rgba(63, 143, 44, 0.12);
+            color: #2d6e20;
+            font-size: 12px;
+            font-weight: 700;
+            letter-spacing: .06em;
+            text-transform: uppercase;
+        }
+        h1 {
+            margin: 18px 0 12px;
+            font-size: clamp(32px, 5vw, 50px);
+            line-height: 1.05;
+        }
+        h2, h3 { margin: 0; }
+        p { color: var(--muted); line-height: 1.7; }
+        .hero-actions,
+        .toolbar,
+        .modal-actions {
+            display: flex;
+            gap: 10px;
+            flex-wrap: wrap;
+        }
+        .btn {
+            border: 0;
+            border-radius: 14px;
+            padding: 12px 18px;
+            font-weight: 700;
+            cursor: pointer;
+        }
+        .btn-primary { background: linear-gradient(135deg, var(--green), #59b83f); color: #fff; }
+        .btn-secondary { background: rgba(15, 109, 181, 0.08); color: var(--blue); }
+        .btn-danger { background: rgba(214, 69, 69, 0.12); color: var(--red); }
+        .stats {
+            display: grid;
+            gap: 16px;
+            grid-template-columns: repeat(4, minmax(0, 1fr));
+            margin-bottom: 22px;
+        }
+        .stat {
+            padding: 18px 20px;
+        }
+        .stat small {
+            color: var(--muted);
+            font-size: 12px;
+            text-transform: uppercase;
+            letter-spacing: .08em;
+        }
+        .stat strong {
+            display: block;
+            margin-top: 10px;
+            font-size: 34px;
+        }
+        .workspace {
+            display: grid;
+            gap: 18px;
+            grid-template-columns: minmax(0, 1.45fr) minmax(280px, 0.8fr);
+        }
+        .section-head {
+            display: flex;
+            justify-content: space-between;
+            align-items: center;
+            gap: 12px;
+            margin-bottom: 16px;
+        }
+        .pill {
+            display: inline-flex;
+            align-items: center;
+            padding: 6px 12px;
+            border-radius: 999px;
+            background: rgba(63, 143, 44, 0.1);
+            color: #2d6e20;
+            font-size: 12px;
+            font-weight: 700;
+        }
+        table {
+            width: 100%;
+            border-collapse: collapse;
+        }
+        th, td {
+            padding: 13px 12px;
+            border-bottom: 1px solid var(--line);
+            text-align: left;
+        }
+        th {
+            color: var(--muted);
+            font-size: 12px;
+            text-transform: uppercase;
+            letter-spacing: .08em;
+        }
+        tr:last-child td { border-bottom: 0; }
+        .segment {
+            display: inline-flex;
+            padding: 5px 10px;
+            border-radius: 999px;
+            background: rgba(15, 109, 181, 0.08);
+            color: var(--blue);
+            font-size: 12px;
+            font-weight: 700;
+        }
+        label {
+            display: grid;
+            gap: 8px;
+            font-size: 14px;
+            font-weight: 700;
+        }
+        input {
+            width: 100%;
+            padding: 12px 14px;
+            border-radius: 14px;
+            border: 1px solid var(--line);
+            font: inherit;
+        }
+        input:focus {
+            outline: 2px solid rgba(15, 109, 181, 0.18);
+            border-color: rgba(15, 109, 181, 0.45);
+        }
+        .status {
+            min-height: 22px;
+            margin-top: 12px;
+            color: var(--muted);
+            font-size: 14px;
+        }
+        .status.error { color: var(--red); }
+        .status.success { color: #2d6e20; }
+        .empty {
+            border: 1px dashed var(--line);
+            border-radius: 18px;
+            text-align: center;
+            padding: 28px;
+            color: var(--muted);
+        }
+        .modal {
+            position: fixed;
+            inset: 0;
+            display: none;
+            justify-content: center;
+            align-items: center;
+            background: rgba(13, 26, 46, 0.5);
+            padding: 18px;
+        }
+        .modal.active { display: flex; }
+        .modal-card {
+            width: min(100%, 460px);
+            padding: 24px;
+        }
+        .close {
+            border: 0;
+            background: transparent;
+            font-size: 24px;
+            color: var(--muted);
+            cursor: pointer;
+        }
+        @media (max-width: 920px) {
+            .hero, .stats, .workspace { grid-template-columns: 1fr; }
+        }
     </style>
 </head>
 <body>
-    <h1>👥 用户管理 - RESTful API 示例</h1>
-    
-    <div class="card">
-        <div style="display: flex; justify-content: space-between; align-items: center;">
-            <h2>用户列表</h2>
-            <button class="btn btn-primary" onclick="openModal()">+ 添加用户</button>
-        </div>
-        <table id="userTable">
-            <thead>
-                <tr>
-                    <th>ID</th>
-                    <th>姓名</th>
-                    <th>邮箱</th>
-                    <th>年龄</th>
-                    <th>操作</th>
-                </tr>
-            </thead>
-            <tbody></tbody>
-        </table>
-    </div>
-    
-    <div class="card">
-        <h2>📖 学习要点</h2>
-        <div class="tip">
-            <strong>RESTful API 设计：</strong>
-            <ul style="margin-top: 10px; padding-left: 20px;">
-                <li><code>GET /api/users</code> - 获取所有用户</li>
-                <li><code>GET /api/users/{id}</code> - 获取单个用户</li>
-                <li><code>POST /api/users</code> - 创建用户</li>
-                <li><code>PUT /api/users/{id}</code> - 更新用户</li>
-                <li><code>DELETE /api/users/{id}</code> - 删除用户</li>
-            </ul>
-        </div>
-        
-        <h3>Controller 代码示例</h3>
-        <pre><code>@RestController
-@RequestMapping("/api/users")
-public class UserController {
-    
-    @GetMapping
-    public List&lt;User&gt; getAllUsers() { ... }
-    
-    @GetMapping("/{id}")
-    public User getUserById(@PathVariable Long id) { ... }
-    
-    @PostMapping
-    public User createUser(@RequestBody User user) { ... }
-    
-    @PutMapping("/{id}")
-    public User updateUser(@PathVariable Long id, @RequestBody User user) { ... }
-    
-    @DeleteMapping("/{id}")
-    public String deleteUser(@PathVariable Long id) { ... }
-}</code></pre>
-    </div>
-    
-    <div class="card">
-        <h2>🔧 Spring 注解说明</h2>
-        <table>
-            <tr><th>注解</th><th>说明</th></tr>
-            <tr><td><code>@RestController</code></td><td>= @Controller + @ResponseBody</td></tr>
-            <tr><td><code>@RequestMapping</code></td><td>定义路由映射</td></tr>
-            <tr><td><code>@GetMapping</code></td><td>GET 请求映射</td></tr>
-            <tr><td><code>@PostMapping</code></td><td>POST 请求映射</td></tr>
-            <tr><td><code>@PathVariable</code></td><td>获取路径变量</td></tr>
-            <tr><td><code>@RequestBody</code></td><td>获取请求体 JSON</td></tr>
-            <tr><td><code>@RequestParam</code></td><td>获取查询参数</td></tr>
-        </table>
-    </div>
-    
-    <p><a href="/">← 返回学习中心</a></p>
-    
-    <!-- 添加/编辑用户模态框 -->
-    <div class="modal" id="userModal">
-        <div class="modal-content">
-            <div class="modal-header">
-                <h3 id="modalTitle">添加用户</h3>
-                <button class="close-btn" onclick="closeModal()">&times;</button>
+<div class="page">
+    <section class="hero">
+        <div class="card hero-main">
+            <span class="eyebrow">Spring Boot demo</span>
+            <h1>User management that feels production-ready.</h1>
+            <p>This page now uses backend stats, keyword search, and clear API error handling instead of a static CRUD example.</p>
+            <div class="hero-actions">
+                <button class="btn btn-primary" onclick="openCreateModal()">Create user</button>
+                <button class="btn btn-secondary" onclick="refreshDashboard()">Refresh</button>
+                <button class="btn btn-secondary" onclick="window.location.href='/'">Back home</button>
             </div>
-            <form id="userForm">
-                <input type="hidden" id="userId">
-                <div class="form-group">
-                    <label>姓名</label>
-                    <input type="text" id="userName" required>
+        </div>
+        <div class="card hero-side">
+            <h3>Highlights</h3>
+            <p>Duplicate emails return a `409`. Validation errors are displayed inline. Search matches both names and emails.</p>
+        </div>
+    </section>
+
+    <section class="stats">
+        <div class="card stat"><small>Total users</small><strong id="totalUsers">0</strong></div>
+        <div class="card stat"><small>Adults</small><strong id="adultUsers">0</strong></div>
+        <div class="card stat"><small>Under 30</small><strong id="youngUsers">0</strong></div>
+        <div class="card stat"><small>Average age</small><strong id="averageAge">0.0</strong></div>
+    </section>
+
+    <section class="workspace">
+        <div class="card table-card">
+            <div class="section-head">
+                <div>
+                    <h2>User directory</h2>
+                    <p>Search results stay in sync with the API.</p>
                 </div>
-                <div class="form-group">
-                    <label>邮箱</label>
-                    <input type="email" id="userEmail" required>
+                <span class="pill" id="resultCount">0 users</span>
+            </div>
+            <div id="tableArea"></div>
+        </div>
+        <div class="card tool-card">
+            <div class="section-head">
+                <div>
+                    <h2>Search</h2>
+                    <p>Use a keyword to match names or emails.</p>
                 </div>
-                <div class="form-group">
-                    <label>年龄</label>
-                    <input type="number" id="userAge" required>
-                </div>
-                <div class="btn-group">
-                    <button type="submit" class="btn btn-primary">保存</button>
-                    <button type="button" class="btn btn-secondary" onclick="closeModal()">取消</button>
+            </div>
+            <form onsubmit="searchUsers(event)">
+                <label>
+                    Keyword
+                    <input id="searchInput" type="text" placeholder="Try: alice or example.com">
+                </label>
+                <div class="toolbar" style="margin-top:14px;">
+                    <button class="btn btn-primary" type="submit">Search</button>
+                    <button class="btn btn-secondary" type="button" onclick="clearSearch()">Clear</button>
                 </div>
             </form>
+            <p>The frontend now explains server-side validation and duplicate email errors instead of silently failing.</p>
+            <div class="status" id="pageStatus"></div>
         </div>
+    </section>
+</div>
+
+<div class="modal" id="userModal">
+    <div class="card modal-card">
+        <div class="section-head">
+            <div>
+                <h2 id="modalTitle">Create user</h2>
+                <p id="modalSubtitle">Add a new user to the in-memory store.</p>
+            </div>
+            <button class="close" onclick="closeModal()" aria-label="Close">&times;</button>
+        </div>
+        <form id="userForm">
+            <input type="hidden" id="userId">
+            <label>Name<input id="userName" maxlength="40" required></label>
+            <label>Email<input id="userEmail" type="email" maxlength="80" required></label>
+            <label>Age<input id="userAge" type="number" min="1" max="120" required></label>
+            <div class="status" id="formStatus"></div>
+            <div class="modal-actions">
+                <button class="btn btn-primary" type="submit">Save</button>
+                <button class="btn btn-secondary" type="button" onclick="closeModal()">Cancel</button>
+            </div>
+        </form>
     </div>
-    
-    <script>
-        // 加载用户列表
-        async function loadUsers() {
-            const res = await fetch('/api/users');
-            const users = await res.json();
-            const tbody = document.querySelector('#userTable tbody');
-            tbody.innerHTML = users.map(u => `
-                <tr>
-                    <td>${u.id}</td>
-                    <td>${u.name}</td>
-                    <td>${u.email}</td>
-                    <td>${u.age}</td>
-                    <td>
-                        <button class="btn btn-primary" onclick="editUser(${u.id}, '${u.name}', '${u.email}', ${u.age})">编辑</button>
-                        <button class="btn btn-danger" onclick="deleteUser(${u.id})">删除</button>
-                    </td>
-                </tr>
-            `).join('');
+</div>
+
+<script>
+    const state = { users: [] };
+
+    async function request(url, options) {
+        const response = await fetch(url, options);
+        const payload = await response.json();
+        if (!response.ok || payload.code !== 0) {
+            const error = new Error(payload.message || 'Request failed');
+            error.details = payload.data;
+            throw error;
         }
-        
-        // 打开模态框
-        function openModal() {
-            document.getElementById('userModal').classList.add('active');
-            document.getElementById('modalTitle').textContent = '添加用户';
-            document.getElementById('userForm').reset();
-            document.getElementById('userId').value = '';
+        return payload;
+    }
+
+    function setStatus(id, message, type = '') {
+        const el = document.getElementById(id);
+        el.textContent = message;
+        el.className = type ? `status ${type}` : 'status';
+    }
+
+    function renderStats(stats) {
+        document.getElementById('totalUsers').textContent = stats.totalUsers;
+        document.getElementById('adultUsers').textContent = stats.adults;
+        document.getElementById('youngUsers').textContent = stats.underThirty;
+        document.getElementById('averageAge').textContent = Number(stats.averageAge).toFixed(1);
+    }
+
+    function renderTable() {
+        const area = document.getElementById('tableArea');
+        document.getElementById('resultCount').textContent = `${state.users.length} users`;
+        if (!state.users.length) {
+            area.innerHTML = '<div class="empty">No users matched the current query.</div>';
+            return;
         }
-        
-        // 关闭模态框
-        function closeModal() {
-            document.getElementById('userModal').classList.remove('active');
+
+        area.innerHTML = `
+            <table>
+                <thead>
+                    <tr><th>ID</th><th>Name</th><th>Email</th><th>Age</th><th>Segment</th><th>Actions</th></tr>
+                </thead>
+                <tbody>
+                    ${state.users.map((user) => `
+                        <tr>
+                            <td>${user.id}</td>
+                            <td>${user.name}</td>
+                            <td>${user.email}</td>
+                            <td>${user.age}</td>
+                            <td><span class="segment">${user.age >= 18 ? 'Adult' : 'Minor'}</span></td>
+                            <td>
+                                <button class="btn btn-secondary" onclick="openEditModal(${user.id})">Edit</button>
+                                <button class="btn btn-danger" onclick="removeUser(${user.id})">Delete</button>
+                            </td>
+                        </tr>
+                    `).join('')}
+                </tbody>
+            </table>
+        `;
+    }
+
+    function openCreateModal() {
+        document.getElementById('userForm').reset();
+        document.getElementById('userId').value = '';
+        document.getElementById('modalTitle').textContent = 'Create user';
+        document.getElementById('modalSubtitle').textContent = 'Add a new user to the in-memory store.';
+        setStatus('formStatus', '');
+        document.getElementById('userModal').classList.add('active');
+    }
+
+    function openEditModal(id) {
+        const user = state.users.find((item) => item.id === id);
+        if (!user) return;
+        document.getElementById('userId').value = user.id;
+        document.getElementById('userName').value = user.name;
+        document.getElementById('userEmail').value = user.email;
+        document.getElementById('userAge').value = user.age;
+        document.getElementById('modalTitle').textContent = 'Edit user';
+        document.getElementById('modalSubtitle').textContent = 'Update the user and keep the email unique.';
+        setStatus('formStatus', '');
+        document.getElementById('userModal').classList.add('active');
+    }
+
+    function closeModal() {
+        document.getElementById('userModal').classList.remove('active');
+    }
+
+    async function refreshDashboard(message = 'Dashboard updated.', type = 'success') {
+        try {
+            const [usersPayload, statsPayload] = await Promise.all([
+                request('/api/users'),
+                request('/api/users/stats')
+            ]);
+            state.users = usersPayload.data;
+            renderStats(statsPayload.data);
+            renderTable();
+            setStatus('pageStatus', message, type);
+        } catch (error) {
+            setStatus('pageStatus', error.message, 'error');
         }
-        
-        // 编辑用户
-        function editUser(id, name, email, age) {
-            document.getElementById('userModal').classList.add('active');
-            document.getElementById('modalTitle').textContent = '编辑用户';
-            document.getElementById('userId').value = id;
-            document.getElementById('userName').value = name;
-            document.getElementById('userEmail').value = email;
-            document.getElementById('userAge').value = age;
+    }
+
+    async function searchUsers(event) {
+        event.preventDefault();
+        const keyword = document.getElementById('searchInput').value.trim();
+        try {
+            if (!keyword) {
+                await refreshDashboard('Showing all users.', 'success');
+                return;
+            }
+            const payload = await request(`/api/users/search?keyword=${encodeURIComponent(keyword)}`);
+            state.users = payload.data;
+            renderTable();
+            setStatus('pageStatus', `Search completed for "${keyword}".`, 'success');
+        } catch (error) {
+            setStatus('pageStatus', error.message, 'error');
         }
-        
-        // 保存用户
-        document.getElementById('userForm').addEventListener('submit', async (e) => {
-            e.preventDefault();
-            const id = document.getElementById('userId').value;
-            const user = {
-                name: document.getElementById('userName').value,
-                email: document.getElementById('userEmail').value,
-                age: parseInt(document.getElementById('userAge').value)
-            };
-            
+    }
+
+    async function clearSearch() {
+        document.getElementById('searchInput').value = '';
+        await refreshDashboard('Showing all users.', 'success');
+    }
+
+    async function removeUser(id) {
+        if (!confirm(`Delete user #${id}?`)) return;
+        try {
+            await request(`/api/users/${id}`, { method: 'DELETE' });
+            await refreshDashboard('User deleted successfully.', 'success');
+        } catch (error) {
+            setStatus('pageStatus', error.message, 'error');
+        }
+    }
+
+    document.getElementById('userForm').addEventListener('submit', async (event) => {
+        event.preventDefault();
+        const id = document.getElementById('userId').value;
+        const payload = {
+            name: document.getElementById('userName').value,
+            email: document.getElementById('userEmail').value,
+            age: Number(document.getElementById('userAge').value)
+        };
+
+        try {
             if (id) {
-                await fetch(`/api/users/${id}`, {
+                await request(`/api/users/${id}`, {
                     method: 'PUT',
                     headers: { 'Content-Type': 'application/json' },
-                    body: JSON.stringify({ ...user, id: parseInt(id) })
+                    body: JSON.stringify(payload)
                 });
+                closeModal();
+                await refreshDashboard('User updated successfully.', 'success');
             } else {
-                await fetch('/api/users', {
+                await request('/api/users', {
                     method: 'POST',
                     headers: { 'Content-Type': 'application/json' },
-                    body: JSON.stringify(user)
+                    body: JSON.stringify(payload)
                 });
+                closeModal();
+                await refreshDashboard('User created successfully.', 'success');
             }
-            
-            closeModal();
-            loadUsers();
-        });
-        
-        // 删除用户
-        async function deleteUser(id) {
-            if (confirm('确定删除此用户？')) {
-                await fetch(`/api/users/${id}`, { method: 'DELETE' });
-                loadUsers();
+        } catch (error) {
+            if (error.details && typeof error.details === 'object') {
+                const firstIssue = Object.values(error.details)[0];
+                setStatus('formStatus', String(firstIssue), 'error');
+            } else {
+                setStatus('formStatus', error.message, 'error');
             }
         }
-        
-        // 初始化
-        loadUsers();
-    </script>
+    });
+
+    refreshDashboard('Latest users loaded.', 'success');
+</script>
 </body>
-</html>
+</html>

src/test/java/com/example/demo/controller/AuthFlowTest.java

@@ -0,0 +1,54 @@
+package com.example.demo.controller;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+
+import java.util.Map;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@SpringBootTest
+@AutoConfigureMockMvc
+class AuthFlowTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private ObjectMapper objectMapper;
+
+    @Test
+    void secureEndpointShouldRejectWithoutToken() throws Exception {
+        mockMvc.perform(get("/api/secure/me"))
+                .andExpect(status().isUnauthorized())
+                .andExpect(jsonPath("$.code").value(401));
+    }
+
+    @Test
+    void shouldAccessSecureEndpointWithValidToken() throws Exception {
+        String loginReq = objectMapper.writeValueAsString(Map.of("username", "admin", "password", "admin123"));
+
+        String loginResp = mockMvc.perform(post("/api/auth/login")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(loginReq))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andReturn().getResponse().getContentAsString();
+
+        String token = objectMapper.readTree(loginResp).path("data").path("token").asText();
+
+        mockMvc.perform(get("/api/secure/me")
+                        .header("Authorization", "Bearer " + token))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andExpect(jsonPath("$.data.principal").value("admin"));
+    }
+}

src/test/java/com/example/demo/controller/UserControllerTest.java

@@ -0,0 +1,91 @@
+package com.example.demo.controller;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@SpringBootTest
+@AutoConfigureMockMvc
+class UserControllerTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Test
+    void shouldListUsersWithApiResponseWrapper() throws Exception {
+        mockMvc.perform(get("/api/users"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andExpect(jsonPath("$.data").isArray());
+    }
+
+    @Test
+    void shouldCreateUser() throws Exception {
+        String json = """
+                {
+                  "name": "Demo User",
+                  "email": "demo-user@example.com",
+                  "age": 22
+                }
+                """;
+
+        mockMvc.perform(post("/api/users")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andExpect(jsonPath("$.data.name").value("Demo User"));
+    }
+
+    @Test
+    void shouldRejectInvalidUser() throws Exception {
+        String json = """
+                {
+                  "name": "",
+                  "email": "bad-mail",
+                  "age": 222
+                }
+                """;
+
+        mockMvc.perform(post("/api/users")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json))
+                .andExpect(status().isBadRequest())
+                .andExpect(jsonPath("$.code").value(400));
+    }
+
+    @Test
+    void shouldRejectDuplicateEmail() throws Exception {
+        String json = """
+                {
+                  "name": "Another User",
+                  "email": "alice@example.com",
+                  "age": 29
+                }
+                """;
+
+        mockMvc.perform(post("/api/users")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json))
+                .andExpect(status().isConflict())
+                .andExpect(jsonPath("$.code").value(409));
+    }
+
+    @Test
+    void shouldExposeUserStats() throws Exception {
+        mockMvc.perform(get("/api/users/stats"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andExpect(jsonPath("$.data.totalUsers").isNumber())
+                .andExpect(jsonPath("$.data.adults").isNumber())
+                .andExpect(jsonPath("$.data.averageAge").isNumber());
+    }
+}

target/classes/application.properties

@@ -1,2 +1,10 @@
 server.port=8082
 spring.application.name=springboot-demo
+
+# 学习友好：默认只保护 /api/secure/**
+learning.auth.enabled=true
+learning.auth.jwt.secret=demo-learning-secret-key-demo-learning-secret-key
+learning.auth.jwt.expiration=86400000
+
+# 避免默认生成密码干扰学习输出
+spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.security.servlet.UserDetailsServiceAutoConfiguration

target/classes/static/aop.html

@@ -28,6 +28,8 @@
         .nav { margin-bottom: 20px; }
         .nav a { margin-right: 15px; color: #6DB33F; text-decoration: none; }
         .nav a:hover { text-decoration: underline; }
+        .lab { background:#fff7e6; border-left:4px solid #fa8c16; padding:15px; border-radius:8px; margin:15px 0; }
+        .lab h4 { color:#ad6800; margin-bottom:8px; }
     </style>
 </head>
 <body>
@@ -38,11 +40,24 @@
     </div>
     
     <h1>🔪 AOP 切面编程</h1>
+
+    <div class="lab">
+        <h4>🧪 实验任务卡（AOP）</h4>
+        <label style="display:block;margin-bottom:8px;"><input id="aopTaskDone" type="checkbox" onchange="toggleAopTaskDone(this)"> 本任务我已经完成</label>
+        <ul style="padding-left:20px;line-height:1.8;">
+            <li>目标：观察同一请求如何触发 Before/After/Around 通知</li>
+            <li>步骤1：调用用户接口 <code>/api/users</code></li>
+            <li>步骤2：回到本页点击“刷新统计数据”</li>
+            <li>预期：统计里能看到 Controller/Service 方法耗时累积</li>
+            <li>常见坑：只看页面不看控制台，容易错过切面日志</li>
+        </ul>
+    </div>
     
     <div class="card">
         <h3>📊 实时性能统计</h3>
         <p>AOP 自动统计所有 Controller 和 Service 方法的执行时间</p>
         <button class="btn btn-primary" onclick="loadStats()">刷新统计数据</button>
+        <button class="btn btn-info" onclick="demoValidationError()">演示校验失败</button>
         <div class="result-box" id="statsResult">点击按钮查看...</div>
     </div>
     
@@ -167,11 +182,41 @@ execution(* com.example.demo.service.*.save*(..))
     <p style="margin-top: 30px;"><a href="/">← 返回学习中心</a></p>
     
     <script>
+        const AOP_TASK_KEY = 'task.aop.done';
+
+        function toggleAopTaskDone(el) {
+            localStorage.setItem(AOP_TASK_KEY, el.checked ? '1' : '0');
+        }
+
+        function initAopTaskState() {
+            const done = localStorage.getItem(AOP_TASK_KEY) === '1';
+            const checkbox = document.getElementById('aopTaskDone');
+            if (checkbox) checkbox.checked = done;
+        }
+
+        async function demoValidationError() {
+            const box = document.getElementById('statsResult');
+            box.textContent = '发送错误示例请求中...';
+            try {
+                const res = await fetch('/api/users', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify({ name: '', email: 'bad', age: 999 })
+                });
+                const data = await res.json();
+                box.textContent = JSON.stringify(data, null, 2);
+            } catch (e) {
+                box.textContent = '错误: ' + e.message;
+            }
+        }
+
         async function loadStats() {
             const res = await fetch('/aop/stats');
             const data = await res.json();
             document.getElementById('statsResult').textContent = JSON.stringify(data, null, 2);
         }
+
+        initAopTaskState();
     </script>
 </body>
 </html>

target/classes/static/events.html

@@ -30,6 +30,8 @@
         .nav { margin-bottom: 20px; }
         .nav a { margin-right: 15px; color: #6DB33F; text-decoration: none; }
         .nav a:hover { text-decoration: underline; }
+        .lab { background:#fff7e6; border-left:4px solid #fa8c16; padding:15px; border-radius:8px; margin:15px 0; }
+        .lab h4 { color:#ad6800; margin-bottom:8px; }
     </style>
 </head>
 <body>
@@ -40,6 +42,18 @@
     </div>
     
     <h1>📡 Spring 事件机制</h1>
+
+    <div class="lab">
+        <h4>🧪 实验任务卡（事件）</h4>
+        <label style="display:block;margin-bottom:8px;"><input id="eventTaskDone" type="checkbox" onchange="toggleEventTaskDone(this)"> 本任务我已经完成</label>
+        <ul style="padding-left:20px;line-height:1.8;">
+            <li>目标：体验发布者与监听者解耦</li>
+            <li>步骤1：输入 userId/userName，点击“发布登录事件”</li>
+            <li>步骤2：重复发布不同用户，比较返回结果</li>
+            <li>预期：接口立即返回；监听处理在日志中可观察</li>
+            <li>常见坑：把事件当同步 RPC，忽略异步监听特性</li>
+        </ul>
+    </div>
     
     <div class="card">
         <h3>🎉 事件发布演示</h3>
@@ -48,6 +62,7 @@
             <input type="text" id="userName" placeholder="用户名" value="张三" style="padding: 10px; border: 1px solid #ddd; border-radius: 4px; width: 150px;">
             <input type="number" id="userId" placeholder="用户ID" value="1" style="padding: 10px; border: 1px solid #ddd; border-radius: 4px; width: 100px;">
             <button class="btn btn-primary" onclick="publishEvent()">发布登录事件</button>
+            <button class="btn btn-warning" onclick="demoEventError()">演示参数错误</button>
         </div>
         <div class="result-box" id="eventResult">等待事件发布...</div>
     </div>
@@ -187,6 +202,29 @@ public class AopEventController {
     <p style="margin-top: 30px;"><a href="/">← 返回学习中心</a></p>
     
     <script>
+        const EVENT_TASK_KEY = 'task.event.done';
+
+        function toggleEventTaskDone(el) {
+            localStorage.setItem(EVENT_TASK_KEY, el.checked ? '1' : '0');
+        }
+
+        function initEventTaskState() {
+            const done = localStorage.getItem(EVENT_TASK_KEY) === '1';
+            const checkbox = document.getElementById('eventTaskDone');
+            if (checkbox) checkbox.checked = done;
+        }
+
+        async function demoEventError() {
+            const resultBox = document.getElementById('eventResult');
+            try {
+                const res = await fetch('/aop/event/publish?userName=', { method: 'POST' });
+                const data = await res.json();
+                resultBox.textContent = JSON.stringify(data, null, 2);
+            } catch (e) {
+                resultBox.textContent = '错误: ' + e.message;
+            }
+        }
+
         async function publishEvent() {
             const userId = document.getElementById('userId').value;
             const userName = document.getElementById('userName').value;
@@ -208,6 +246,8 @@ public class AopEventController {
                 document.getElementById('eventResult').textContent = '错误: ' + e.message;
             }
         }
+
+        initEventTaskState();
     </script>
 </body>
 </html>

target/classes/static/index.html

@@ -68,6 +68,10 @@
                 <h4>📡 事件机制</h4>
                 <p>发布/订阅模式、解耦业务逻辑</p>
             </a>
+            <a href="/learn" class="feature-item">
+                <h4>🔐 鉴权演示（学习用）</h4>
+                <p>最小 JWT 流程：登录、携带 Token、访问受保护接口</p>
+            </a>
         </div>
     </div>
     

target/classes/static/users.html

@@ -143,7 +143,8 @@ public class UserController {
         // 加载用户列表
         async function loadUsers() {
             const res = await fetch('/api/users');
-            const users = await res.json();
+            const payload = await res.json();
+            const users = payload.data || [];
             const tbody = document.querySelector('#userTable tbody');
             tbody.innerHTML = users.map(u => `
                 <tr>
@@ -196,7 +197,7 @@ public class UserController {
                 await fetch(`/api/users/${id}`, {
                     method: 'PUT',
                     headers: { 'Content-Type': 'application/json' },
-                    body: JSON.stringify({ ...user, id: parseInt(id) })
+                    body: JSON.stringify(user)
                 });
             } else {
                 await fetch('/api/users', {

target/maven-archiver/pom.properties

@@ -1,3 +0,0 @@
-artifactId=demo
-groupId=com.example
-version=0.0.1-SNAPSHOT

target/maven-status/maven-compiler-plugin/compile/default-compile/createdFiles.lst

@@ -1,15 +1,25 @@
+com/example/demo/controller/auth/SecureDemoController.class
+com/example/demo/exception/ResourceNotFoundException.class
+com/example/demo/event/UserEventPublisher.class
+com/example/demo/exception/GlobalExceptionHandler.class
+com/example/demo/dto/auth/LoginRequest.class
+com/example/demo/DemoApplication.class
+com/example/demo/controller/PageController.class
+com/example/demo/dto/UserRequest.class
+com/example/demo/security/LearningJwtUtil.class
+com/example/demo/security/LearningSecurityConfig.class
+com/example/demo/model/UserEvent$Type.class
+com/example/demo/model/User.class
+com/example/demo/service/UserService.class
+com/example/demo/aop/PerformanceAspect.class
 com/example/demo/aop/RateLimited.class
 com/example/demo/model/UserEvent.class
 com/example/demo/aop/LoggingAspect.class
-com/example/demo/event/UserEventPublisher.class
+com/example/demo/controller/auth/LearningAuthController.class
+com/example/demo/common/ApiResponse.class
 com/example/demo/controller/AopEventController.class
 com/example/demo/controller/LearnController.class
-com/example/demo/DemoApplication.class
 com/example/demo/event/UserEventListener.class
-com/example/demo/controller/PageController.class
 com/example/demo/controller/UserController.class
-com/example/demo/model/UserEvent$Type.class
-com/example/demo/model/User.class
 com/example/demo/aop/RateLimitAspect.class
-com/example/demo/service/UserService.class
-com/example/demo/aop/PerformanceAspect.class
+com/example/demo/security/LearningJwtFilter.class

target/maven-status/maven-compiler-plugin/compile/default-compile/inputFiles.lst

@@ -1,14 +1,24 @@
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/security/LearningSecurityConfig.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/auth/SecureDemoController.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/UserController.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/model/User.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/aop/LoggingAspect.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/security/LearningJwtUtil.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/PageController.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/aop/RateLimited.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/aop/PerformanceAspect.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/service/UserService.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/exception/ResourceNotFoundException.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/AopEventController.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/exception/GlobalExceptionHandler.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/event/UserEventPublisher.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/dto/auth/LoginRequest.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/dto/UserRequest.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/common/ApiResponse.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/security/LearningJwtFilter.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/DemoApplication.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/event/UserEventListener.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/LearnController.java
+/home/llm/projects/springboot-demo/src/main/java/com/example/demo/controller/auth/LearningAuthController.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/model/UserEvent.java
 /home/llm/projects/springboot-demo/src/main/java/com/example/demo/aop/RateLimitAspect.java

target/maven-status/maven-compiler-plugin/testCompile/default-testCompile/createdFiles.lst

@@ -0,0 +1,2 @@
+com/example/demo/controller/UserControllerTest.class
+com/example/demo/controller/AuthFlowTest.class

target/maven-status/maven-compiler-plugin/testCompile/default-testCompile/inputFiles.lst

@@ -0,0 +1,2 @@
+/home/llm/projects/springboot-demo/src/test/java/com/example/demo/controller/AuthFlowTest.java
+/home/llm/projects/springboot-demo/src/test/java/com/example/demo/controller/UserControllerTest.java

target/surefire-reports/com.example.demo.controller.AuthFlowTest.txt

@@ -0,0 +1,4 @@
+-------------------------------------------------------------------------------
+Test set: com.example.demo.controller.AuthFlowTest
+-------------------------------------------------------------------------------
+Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.666 s -- in com.example.demo.controller.AuthFlowTest

target/surefire-reports/com.example.demo.controller.UserControllerTest.txt

@@ -0,0 +1,4 @@
+-------------------------------------------------------------------------------
+Test set: com.example.demo.controller.UserControllerTest
+-------------------------------------------------------------------------------
+Tests run: 3, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 24.99 s -- in com.example.demo.controller.UserControllerTest