AOP的After增强

爱被打了一巴掌 2021-07-24 20:18 471阅读 0赞

**一 配置**

<?xml version="1.0" encoding="GBK"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns:context="http://www.springframework.org/schema/context"
         xmlns:aop="http://www.springframework.org/schema/aop"
         xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
         http://www.springframework.org/schema/context
         http://www.springframework.org/schema/context/spring-context-4.0.xsd
         http://www.springframework.org/schema/aop
         http://www.springframework.org/schema/aop/spring-aop-4.0.xsd">
         
         <context:component-scan
               base-package="org.crazyit.app.service
               ,org.crazyit.app.aspect">
               <context:include-filter type="annotation"
                    expression="org.aspectj.lang.annotation.Aspect"  />
         </context:component-scan>
         
         <aop:aspectj-autoproxy />
    </beans>

**二 切面类**

package org.crazyit.app.aspect;
    
    import org.aspectj.lang.annotation.*;
    import org.aspectj.lang.*;
    
    // 定义一个切面
    @Aspect
    public class ReleaseAspect
    {
        // 匹配org.crazyit.app.service包下所有类的、
        // 所有方法的执行作为切入点
        @After("execution(* org.crazyit.app.service.*.*(..))")
        public void release()
        {
            System.out.println("模拟方法结束后的释放资源...");
        }
    }

**三 接口**

Hello

package org.crazyit.app.service;
    
    public interface Hello {
         // 定义一个简单方法，模拟应用中的业务逻辑方法
         void foo();
         // 定义一个addUser()方法，模拟应用中的添加用户的方法
         int addUser(String name, String pass);
    }

World

package org.crazyit.app.service;
    
    public interface World {
         // 定义一个简单方法，模拟应用中的业务逻辑方法
         public void bar();
    }

**四 实现类**

HelloImpl

package org.crazyit.app.service.impl;
    
    
    import org.springframework.stereotype.Component;
    
    
    import org.crazyit.app.service.*;
    
    @Component("hello")
    public class HelloImpl implements Hello
    {
        // 定义一个简单方法，模拟应用中的业务逻辑方法
        public void foo()
        {
            System.out.println("执行Hello组件的foo()方法");
        }
        // 定义一个addUser()方法，模拟应用中的添加用户的方法
        public int addUser(String name , String pass)
        {
            System.out.println("执行Hello组件的addUser添加用户：" + name);
            if(name.length() < 3 || name.length() > 10)
            {
                throw new IllegalArgumentException("name参数的长度必须大于3，小于10！");
            }
            return 20;
        }
    }

WorldImpl

package org.crazyit.app.service.impl;
    
    
    import org.springframework.stereotype.Component;
    import org.crazyit.app.service.*;
    
    @Component("world")
    public class WorldImpl implements World {
        // 定义一个简单方法，模拟应用中的业务逻辑方法
        public void bar() {
            System.out.println("执行World组件的bar()方法");
        }
    }

**五 测试类**

package lee;
    
    import org.springframework.context.*;
    import org.springframework.context.support.*;
    import org.crazyit.app.service.*;
    
    public class BeanTest {
        public static void main(String[] args) {
            // 创建Spring容器
            ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");
            Hello hello = ctx.getBean("hello", Hello.class);
            hello.foo();
            hello.addUser("悟空", "7788");
            World world = ctx.getBean("world", World.class);
            world.bar();
        }
    }

**六 测试结果**

执行Hello组件的foo()方法
    模拟方法结束后的释放资源...
    执行Hello组件的addUser添加用户：悟空
    模拟方法结束后的释放资源...
    Exception in thread "main" java.lang.IllegalArgumentException:  name参数的长度必须大于3，小于10！
         at  org.crazyit.app.service.impl.HelloImpl.addUser(HelloImpl.java:30)
         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native  Method)
         at  sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
         at  sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
         at java.lang.reflect.Method.invoke(Method.java:498)
         at  org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
         at  org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
         at  org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
         at  org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:43)
         at  org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
         at  org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
         at  org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
         at  org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
         at com.sun.proxy.$Proxy7.addUser(Unknown Source)
         at lee.BeanTest.main(BeanTest.java:26)