Spring AOP 之 HelloWorld（简单例子）

java代码

Java代码



import org.aspectj.lang.JoinPoint;

import org.aspectj.lang.ProceedingJoinPoint;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class AopTest {

/**

* @param args

*/

public static void main(String[] args) {

ApplicationContext ctx = new ClassPathXmlApplicationContext("benx.xml");

HelloWorld helloWorld = (HelloWorld) ctx.getBean("helloWorld");

helloWorld.sayHelloWorld();

}

}

interface HelloWorld {

void sayHelloWorld();

}

interface HelloChina {

void sayHelloChina();

}

class HelloWorldImpl implements HelloWorld {

public void sayHelloWorld() {

System.out.println("Hello World!");

//制造异常

String str = null;

str.substring(1);

}

}

/**

* 日志拦截器

*

* @author jin.xiong

*

*/

class LogAdvice {

/**

* 执行方法前拦截器

*

* @param joinPoint

*/

public void methodBefore(JoinPoint joinPoint) {

System.out.println(joinPoint.getTarget().getClass().getName() + "."

+ joinPoint.getSignature().getName() + " Start");

}

/**

* 方法执行后拦截器

*

* @param joinPoint

*/

public void methodAfter(JoinPoint joinPoint) {

System.out.println(joinPoint.getTarget().getClass().getName() + "."

+ joinPoint.getSignature().getName() + " end");

}

/**

* 方法出现异常拦截器

*

* @param joinPoint

*/

public void methodException(JoinPoint joinPoint) {

System.out.println(joinPoint.getTarget().getClass().getName() + "."

+ joinPoint.getSignature().getName() + " mett Error");

}

/**

* 方法环绕拦截器，如果使用了这个，可以忽视上面的方法

* 注意该方法参数为ProceedingJoinPoint ，这是可以执行的，只有round可以使用

* @param joinPoint

* @return

*/

public Object methodRound(ProceedingJoinPoint joinPoint) {

methodBefore(joinPoint);

Object ob = null;

try {

ob = joinPoint.proceed();

} catch (Throwable error) {

methodException(joinPoint);

}

methodAfter(joinPoint);

return ob;

}

}

benx.xml

Java代码



<?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-2.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
<bean id="helloWorld" class="HelloWorldImpl"/>

<bean id="logAdvice" class="LogAdvice"/>

<aop:config>

<aop:aspect ref="logAdvice">

<aop:pointcut id="logPointcut" expression="execution(* *.*(..))" />

<aop:before method="methodBefore" pointcut-ref="logPointcut" />

<aop:after method="methodAfter" pointcut-ref="logPointcut" />

<aop:after-throwing method="methodException" pointcut-ref="logPointcut" />

<!-- aroun最好不要和他们同时使用 -->

<aop:around method="methodRound" pointcut-ref="logPointcut" />

</aop:aspect>

</aop:config>

</beans>

打印结果，之所以会重复，使用为使用了round，可以把benx.xml中的methodRound去掉

Java代码



HelloWorldImpl.sayHelloWorld Start

HelloWorldImpl.sayHelloWorld Start

Hello World!

HelloWorldImpl.sayHelloWorld end

HelloWorldImpl.sayHelloWorld mett Error

HelloWorldImpl.sayHelloWorld mett Error

HelloWorldImpl.sayHelloWorld end