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此段小代码演示了spring aop中@Around @Before @After三个注解的区别

@Before是在所拦截方法执行之前执行一段逻辑。

@After 是在所拦截方法执行之后执行一段逻辑。

@Around是可以同时在所拦截方法的前后执行一段逻辑。

package com.itsoft.action;import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Controller;/*** * @author zxf* 演示aop测试类*/
@Controller
public class UserAction {public void queryUsers(){System.out.println("查询所有用户【all users list】");}public static void main(String[] args) {ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("application-aop.xml");UserAction userAction = (UserAction)ctx.getBean("userAction");userAction.queryUsers();ctx.destroy();}
}

package com.itsoft;import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;/*** * @author Administrator* 通过aop拦截后执行具体操作*/
@Aspect
@Component
public class LogIntercept {@Pointcut("execution(public * com.itsoft.action..*.*(..))")public void recordLog(){}@Before("recordLog()")public void before() {this.printLog("已经记录下操作日志@Before 方法执行前");}@Around("recordLog()")public void around(ProceedingJoinPoint pjp) throws Throwable{this.printLog("已经记录下操作日志@Around 方法执行前");pjp.proceed();this.printLog("已经记录下操作日志@Around 方法执行后");}@After("recordLog()")public void after() {this.printLog("已经记录下操作日志@After 方法执行后");}private void printLog(String str){System.out.println(str);}
}

演示@Around @Before @After 区别

<?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"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-3.0.xsdhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsdhttp://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"><context:annotation-config /><context:component-scan base-package="com.itsoft"/><aop:aspectj-autoproxy />
</beans>