springboot实现aop

AOP(术语)

1. 连接点
   类里面哪些方法可以增强，这些点被称为连接点

2. 切入点
   实际被真正增强的方法

3. 通知（增强）
   实际增强的逻辑部分称为通知（增强）
   通知（增强）有多种类型

• 前置通知–@Before
• 后置通知–@After
• 环绕通知–@Around
• 异常通知–@AfterThrowing
• 最终通知–@AfterReturning
  切面（是动作）–
  把通知（增强）应用到切入点过程

引入依赖

<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-aop</artifactId></dependency></dependencies>

实现步骤

1. 新建一个注解类，用于后面做切入点

@Retention(value = RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Authorization {}

2. 建一个切面类

@Aspect
@Component
public class AuthAspect {/*** 定义了一个切点* 这里的路径填自定义注解的全路径*/@Pointcut("@annotation(com.zhuyh.studytest.spring5.aop.Authorization)")public void authornizeCut() {}@Before("authornizeCut()")public void cutProcess(JoinPoint joinPoint) {MethodSignature signature = (MethodSignature) joinPoint.getSignature();Method method = signature.getMethod();System.out.println("AOP开始拦截, 当前拦截的方法名: " + method.getName());}@After("authornizeCut()")public void after(JoinPoint joinPoint) {MethodSignature signature = (MethodSignature) joinPoint.getSignature();Method method = signature.getMethod();System.out.println("AOP执行的方法 :" + method.getName() + " 执行完了");}@Around("authornizeCut()")public Object testCutAround(ProceedingJoinPoint joinPoint) throws Throwable {System.out.println("AOP拦截开始进入环绕通知.......");Object proceed = joinPoint.proceed();System.out.println("准备退出环绕......");return proceed;}/*** returning属性指定连接点方法返回的结果放置在result变量中** @param joinPoint 连接点* @param result    返回结果*/@AfterReturning(value = "authornizeCut()", returning = "result")public void afterReturn(JoinPoint joinPoint, Object result) {MethodSignature signature = (MethodSignature) joinPoint.getSignature();Method method = signature.getMethod();System.out.println("AOP拦截的方法执行成功, 进入返回通知拦截, 方法名为: " + method.getName() + ", 返回结果为: " + result.toString());}@AfterThrowing(value = "authornizeCut()", throwing = "e")public void afterThrow(JoinPoint joinPoint, Exception e) {MethodSignature signature = (MethodSignature) joinPoint.getSignature();Method method = signature.getMethod();System.out.println("AOP进入方法异常拦截, 方法名为: " + method.getName() + ", 异常信息为: " + e.getMessage());}
}

3. 来一个Controller作为请求被代理的对象

@RestController
@RequestMapping("/company")
public class CompanyController {@GetMapping("/aopTest")@Authorizationpublic Object aopTest(@RequestParam String name){//远程调用System.out.println("执行接口name:" + name);// int n = 1/0;return "成功了-----" + name;}
}

4. 启动类启动项目

@SpringBootApplication
public class StudyTestApplication {public static void main(String[] args) {SpringApplication.run(StudyTestApplication.class, args);}
}

测试验证

1. 浏览器或者api调用工具调接口
   
2. 控制台打印

AOP拦截开始进入环绕通知.......
AOP开始拦截, 当前拦截的方法名: aopTest
执行接口name:zhuyh
AOP拦截的方法执行成功, 进入返回通知拦截, 方法名为: aopTest, 返回结果为: 成功了-----zhuyh
AOP执行的方法 :aopTest 执行完了
准备退出环绕......

3. Controller加入一个异常 int i=1/0; 重启项目再次调用
   异常通知打印了 / by zero

AOP拦截开始进入环绕通知.......
AOP开始拦截, 当前拦截的方法名: aopTest
执行接口name:zhuyh
AOP进入方法异常拦截, 方法名为: aopTest, 异常信息为: / by zero
AOP执行的方法 :aopTest 执行完了
2024-01-24 16:50:10.477 ERROR 4888 --- [nio-8080-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.ArithmeticException: / by zero] with root causejava.lang.ArithmeticException: / by zeroat com.zhuyh.studytest.spring5.aop.CompanyController.aopTest(CompanyController.java:16) ~[classes/:na]

感谢阅读

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