spring中的动态代理和aop的自定义通知

本是古典何须时尚 2021-09-19 04:58 255阅读 0赞

**目录**

1.spring中的动态代理

2.aop的自定义通知和配置（before，after，afterReturning，afterThrowing，around）

# 1.spring中的动态代理  #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70][]

UserService.java:

package com.sikiedu.service;
    
    public interface UserService {
    
    	 void save();
    	 void delete();
    	 void update();
    	 void find();
    	
    }

UserServicelmpl.java:

package com.sikiedu.service;
    
    public class UserServicelmpl implements UserService {
    
    	@Override
    	public void save() {
    		System.out.println("save");
    	}
    
    	@Override
    	public void delete() {
    		System.out.println("delete");
    	}
    
    	@Override
    	public void update() {
    		System.out.println("update");
    	}
    
    	@Override
    	public void find() {
    		System.out.println("find");
    	}
    
    }

UserServiceProxy.java:

package com.sikiedu.test;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.lang.reflect.Proxy;
    
    import com.sikiedu.service.UserService;
    import com.sikiedu.service.UserServicelmpl;
    
    public class UserServiceProxy {
    
    	public UserService getUserServiceProxy(UserService us){
    		
    		return (UserService)Proxy.newProxyInstance(UserService.class.getClassLoader(),
    				UserServicelmpl.class.getInterfaces(),
    				new InvocationHandler() {
    					
    					@Override
    					public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
    						System.out.println("开启事务");
    						Object invoke=method.invoke(us, args);
    						System.out.println("提交/回滚");
    						return invoke;
    						
    					}
    				});
    	}
    }

AopTest.java:

package com.sikiedu.test;
    
    import org.junit.Test;
    
    import com.sikiedu.service.UserService;
    import com.sikiedu.service.UserServicelmpl;
    
    public class AopTest {
    
    	@Test
    	public void Test(){
    		UserServiceProxy usProxy=new UserServiceProxy();
    		UserService us=new UserServicelmpl();
    		UserService us_PowerUp= usProxy.getUserServiceProxy(us);
    		us_PowerUp.find();
    	}
    }

运行结果：

![20190502124130501.png][]

# 2.aop的自定义通知和配置（before，after，afterReturning，afterThrowing，around） #

导入包：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 1][]

导入aop约束:

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 2][]

新建applicationContext.xml，并右键点击：【openwith】-【other...】-【spring config editor】-【namespace】-【勾选aop，beans】

![20190502130814560.png][]

然后applicationContext.xml就有如下约束了：

# ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 3][] #

MyAdvice.java:

package ssm.sikiedu.aop;
    
    import org.aspectj.lang.ProceedingJoinPoint;
    
    public class MyAdvice {
    
    	//before 前置通知 在目标方法前调用
    	public void before(){
    		System.out.println("before");
    	}
    	
    	//after 最终通知（后置通知） 在目标方法后调用，无论是否出现异常都会执行 类似finally
    	public void after(){
    		System.out.println("after");
    	}
    	
    	//afterReturning 成功通知（后置通知） 在目标方法执行后，并且执行成功才调用，如果方法出现异常则不调用
    	public void afterReturning(){
    		System.out.println("afterReturning");
    	}
    	
    	//afterThrowing 异常通知（后置通知） 在目标方法执行出现异常的时候才会调用
    	public void afterThrowing(){
    		System.out.println("afterThrowing");
    	}
    	
    	//环绕通知
    	public Object around(ProceedingJoinPoint pjp) throws Throwable{
    		
    		System.out.println("around before");
    		Object proceed = pjp.proceed();
    		System.out.println("around after");
    		return proceed;
    	}
    }

applicationContext.xml:

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
    	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    	xmlns:aop="http://www.springframework.org/schema/aop"
    	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
    		http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd">
    
    
    	<bean name="userService" class="com.sikiedu.service.UserServicelmpl"></bean>
    	
    
    	<bean name="myAdvice" class="ssm.sikiedu.aop.MyAdvice"></bean>
    	
    	<aop:config>
    
    
    
    
    		<aop:pointcut id="servicePc" expression="execution(public void com.sikiedu.service.UserServicelmpl.save())"/>
    		
    		
    
    		<aop:aspect ref="myAdvice">
    
    			<aop:before method="before" pointcut-ref="servicePc"/>
    			
    
    			<aop:after method="after" pointcut-ref="servicePc"/>
    			
    
    			<aop:after-returning method="afterReturning" pointcut-ref="servicePc"/>
    			
    
    			<aop:after-throwing method="afterThrowing" pointcut-ref="servicePc"/>
    			
    
    			<aop:around method="around" pointcut-ref="servicePc"/>
    		</aop:aspect>
    	</aop:config>
    </beans>

AopTest.java:

package com.sikiedu.test;
    
    import javax.annotation.Resource;
    
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.test.context.ContextConfiguration;
    import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
    
    import com.sikiedu.service.UserService;
    import com.sikiedu.service.UserServicelmpl;
    
    @RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration("classpath:applicationContext.xml")
    public class AopTest {
    
    	@Resource(name="userService")
    	UserService us;
    	@Test
    	public void Test2(){
    		us.delete();
    	}
    }

运行结果：（**下面是正常运行的结果，但是我并没有运行成功**）

![20190502161558991.png][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70]: /images/20210725/54489b1b1f45401e977008fee137d475.png
[20190502124130501.png]: /images/20210725/724847e2d1c94c2ba1db1692cb8217ed.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 1]: /images/20210725/457ad6ed207c4682be0751773b289bf8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 2]: /images/20210725/f83b1504e3f04e709385e4356d7f6ac7.png
[20190502130814560.png]: /images/20210725/b1352e56c6b94901b185bc9f77852797.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMzIzMjU2_size_16_color_FFFFFF_t_70 3]: /images/20210725/47137f0159814a7297b94811e100ce91.png
[20190502161558991.png]: /images/20210725/391fb8faac3b4452b85702235b8e9bc3.png