Java

面向切面的Spring

略

  • 面向切面编程的基本原理
  • 通过POJO创建切面
  • 使用@AspectJ注解
  • 为AspectJ切面注入依赖

面向切面的编程

定义术语

  1. 通知(Advice)
  2. 连接点(Join point)
  3. 切点(Pointcut)
  4. 切面(Aspect)
  5. 引入(introduction)
  6. 织入(Weaving)

使用xml

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<aop:config expose-proxy="true" proxy-target-class="true">

        <aop:pointcut id="test_point_cut" expression="execution(* com.yuda.component.MyTest.*(..))"/>

        <aop:aspect ref="my_advice">

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

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

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

            <aop:after-returning method="afterReturning" pointcut-ref="test_point_cut" returning="val"/>

        </aop:aspect>
    </aop:config>

使用注解

xml

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<aop:aspectj-autoproxy proxy-target-class="true"/>

java

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@Aspect
public class MyAspect {
    @Pointcut("execution(* *.*(..))")
    public void myPointCut(){}

    @Before("myPointCut()")
    public void before() {
        System.out.println("MyAspect.before");
    }

    @After("myPointCut()")
    public void after(){
        System.out.println("MyAspect.after");
    }

    @Around("myPointCut()")
    public Object around(ProceedingJoinPoint pjp){

        Object proceed = null;
        try {
            System.out.println("前");
            System.out.println(pjp.getSignature().getName());
            proceed = pjp.proceed();
            System.out.println(pjp.getSignature().getName());
            System.out.println("后");
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
        return proceed;
    }

    @AfterReturning(value = "myPointCut()",returning = "val")
    public void afterReturning(JoinPoint jp,Object val){
        System.out.println("啦啦啦啦"+jp.getSignature().getName());
        System.out.println("MyAspect.afterReturning");
    }
}