ASpectJ对AOP的实现

切入点表达式

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基于注解

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@Aspect // 表示当前类切面
public class MyAspect {

    @Before("execution(* *..ISomeService.doFirst(..))")
    public void before(JoinPoint jp) {
        System.out.println("执行 before2" + jp);
    }

    @AfterReturning(value = "execution(* *..ISomeService.doSecond(..))", returning = "result")
    public void myAfterReturning(Object result) {
        System.out.println("执行 my after, result" + result);
    }

    // 定义了一个切入点
    @Pointcut("execution(* *..ISomeService.doThird(..))")
    public void doThirdPointCut(){}

    @Around("doThirdPointCut()")
    public Object myAround(ProceedingJoinPoint pp) throws Throwable {
        System.out.println("执行around1");
        Object res = pp.proceed();
        System.out.println("执行around2 " + res);
        return res;
    }

}

        <bean id="myAspect" class="day1208.MyAspectXML"/>
        <bean id="someService" class="day1208.ServiceImpl"/>
        <aop:aspectj-autoproxy/>

如果运行的时候出现error at ::0 can't find referenced pointcut, 一般是因为jdk版本和AspectJ.Weaver不一致.

1.6以下的aspectj需要用jdk1.6运行. 

基于XML

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public class MyAspectXML {

    public void before(JoinPoint jp) {
        System.out.println("执行 before2" + jp);
    }

    public void myAfterReturning(Object result) {
        System.out.println("执行 my after, result" + result);
    }
    public void myAfterReturning() {
        System.out.println("执行 my after, no result");
    }

    public void doThirdPointCut(){}

    public Object myAround(ProceedingJoinPoint pp) throws Throwable {
        System.out.println("执行around1");
        Object res = pp.proceed();
        System.out.println("执行around2 " + res);
        return res;
    }

}

        <aop:config>
                <aop:pointcut id="secondPT" expression="execution(* *..ISomeService.doSecond(..))"/>
                <aop:aspect ref="myAspect">
                        <aop:before method="before" pointcut="execution(* *..ISomeService.doFirst(..))"/>
                        <aop:after-returning method="myAfterReturning(java.lang.Object)" pointcut-ref="secondPT" returning="result"/>
                </aop:aspect>
        </aop:config>