1. 自己定义的拦截注解

package com.spring.aop;import java.lang.annotation.Documented;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;@Retention(RetentionPolicy.RUNTIME)@Target({ElementType.ANNOTATION_TYPE,ElementType.METHOD,ElementType.TYPE})@Documentedpublic @interface MyAction {    String value();}

2. 定义aop切点

package com.spring.aop;import java.lang.reflect.Method;import org.aspectj.lang.JoinPoint;import org.aspectj.lang.annotation.After;import org.aspectj.lang.annotation.Aspect;import org.aspectj.lang.annotation.Before;import org.aspectj.lang.annotation.Pointcut;import org.aspectj.lang.reflect.MethodSignature;import org.springframework.stereotype.Component;@Aspect@Componentpublic class MyAop {    //切点切入自己配置的那个注解MyAction    @Pointcut("@annotation(com.spring.aop.MyAction)") //注意这里的写法    public void annotationPointCat(){}        @Before("annotationPointCat()")//位置为这个包下的所有类、所有方法、不论参数是什么类型    public void before(JoinPoint joinPoint){        MethodSignature signature = (MethodSignature) joinPoint.getSignature();        Method method = signature.getMethod();        MyAction myAction =  method.getAnnotation(MyAction.class);        System.out.println("before: "+myAction.value());    }        @After("annotationPointCat()")    public void after(JoinPoint joinPoint){        MethodSignature signature = (MethodSignature) joinPoint.getSignature();        Method method = signature.getMethod();        MyAction myAction =  method.getAnnotation(MyAction.class);        System.out.println("after: "+myAction.value());    }}

3. 编写服务类，应用切面

package com.spring.aop;import org.springframework.stereotype.Component;@Componentpublic class MyServer {
　　/*
　　显而易见，利用注解式拦截，会提高切面的复用率
　　*/    @MyAction("ser01")    public void ser01(){        System.out.println("call ser01");    }        @MyAction("ser02")    public void ser02(){        System.out.println("call ser02");    }}

4. Spring配置文件（APP.xml）

<context:component-scan base-package="com.spring.aop"></context:component-scan>     <!-- 使 AspectJ 的注解起作用 ； autoproxy自动代理-->    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>

5. 运行   

 public static void main(String[] args) {        BeanFactory factory = new ClassPathXmlApplicationContext("com/spring/ioc/APP.xml");        MyServer myServer = factory.getBean(MyServer.class);        myServer.ser01();                myServer.ser02(); }

依赖jar包    
<!-- Spring -->        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-context</artifactId>            <version>${org.springframework-version}</version>            <exclusions>                <!-- Exclude Commons Logging in favor of SLF4j -->                <exclusion>                    <groupId>commons-logging</groupId>                    <artifactId>commons-logging</artifactId>                 </exclusion>            </exclusions>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-webmvc</artifactId>            <version>${org.springframework-version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-aop</artifactId>            <version>${org.springframework-version}</version>        </dependency>                        <!-- AspectJ -->        <dependency>            <groupId>org.aspectj</groupId>            <artifactId>aspectjrt</artifactId>            <version>${org.aspectj-version}</version>        </dependency>         <!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver -->        <dependency>            <groupId>org.aspectj</groupId>            <artifactId>aspectjweaver</artifactId>            <version>${org.aspectj-version}</version>        </dependency>        

异常：
Caused by: java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException

是因为缺少 aspectjweaver 包