初学AOP

Posted 2020-08-22 何甜甜在吗

src\dayday\Count.java

package dayday;

import org.springframework.stereotype.Component;

/**
 * Created by I am master on 2016/12/3.
 */
@Component
public interface Count {
   int add(int i, int j);
   int mul(int i, int j);
   int div(int i, int j);
   int sub(int i, int j);
}

src\dayday\CountImpl.java

package dayday;

import dayday.Count;
import org.springframework.stereotype.Component;

/**
 * Created by I am master on 2016/12/3.
 */
@Component
public class CountImpl implements Count {
    public int add(int i,int j){
        int result=i+j;
        return result;
    }
    public int sub(int i,int j){
        int result=i-j;
        return result;
    }
    public int mul(int i,int j){
        int result=i*j;
        return result;
    }
    public int div(int i,int j){
        int result=i/j;
        return result;
    }
}

src\dayday\LogginAspect.java

package dayday;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;

import org.springframework.stereotype.Component;

import java.util.Arrays;
import java.util.List;

/**
 * Created by I am master on 2016/12/3.
 */
@Aspect
@Component
public class LogginAspect {
    @Before("execution(public int dayday.Count.add(int,int))")
    public  void beforeMethod(JoinPoint joinpoint){
        String methodName=joinpoint.getSignature().getName();
        List<Object>args= Arrays.asList(joinpoint.getArgs());
        System.out.println("method is "+methodName+" begins with "+args);
    }
    @After("execution(public int dayday.Count.add(int,int))")
    public void afterMethod(){
        System.out.println("After...");
    }
    @AfterReturning(value="execution(public int dayday.Count.add(int,int))",returning = "result")
    public void afterReturning(JoinPoint joinpoint,Object result){
         String methodName=joinpoint.getSignature().getName();
         System.out.println("method is "+methodName+" result is "+result);
    }
    @AfterThrowing(value="execution(public int dayday.Count.div(int,int))",throwing ="exception")
    public void afterThrowing(JoinPoint joinpoint,Exception exception){
        String methodName=joinpoint.getSignature().getName();
        System.out.println("method is "+methodName+" occurs "+exception);
    }
    @Around("execution(public int dayday.Count.add(int,int))")
    public Object aroundMethod(ProceedingJoinPoint pjd){

        Object result = null;
        String methodName = pjd.getSignature().getName();

        try {
            //前置通知
            System.out.println("The method " + methodName + " begins with " + Arrays.asList(pjd.getArgs()));
            //执行目标方法
            result = pjd.proceed();
            //返回通知
            System.out.println("The method " + methodName + " ends with " + result);
        } catch (Throwable e) {
            //异常通知
            System.out.println("The method " + methodName + " occurs exception:" + e);
            throw new RuntimeException(e);
        }
        //后置通知
        System.out.println("The method " + methodName + " ends");
        return result;
    }
}

src\dayday\Main.java

package dayday;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * Created by I am master on 2016/12/3.
 */
public class Main {
    public static void main(String[] args){
        ApplicationContext ctx=new ClassPathXmlApplicationContext("beans.xml");
        Count c = ctx.getBean(Count.class);
        int result=c.add(8,3);
    }
}

src\beans.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:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
       <context:component-scan base-package="dayday"/>
       <!--使AspectJ注释起作用，自动为匹配的类生成代理对象-->
       <aop:aspectj-autoproxy/>
</beans>