Scheme base方式实现通知（Spring Aop）

喜欢ヅ旅行 2023-06-06 07:57 38阅读 0赞

使用Scheme Aop方式来实现Spring Aop，分别有前置通知，后置通知，环绕通知，异常通知。

## **前置通知：（实现MethodBeforeAdvice接口）** ##

package com.bjsxt.advice;
    
    import org.springframework.aop.MethodBeforeAdvice;
    
    import java.lang.reflect.Method;
    
    public class BeforAdvice  implements MethodBeforeAdvice {
    
        /**
         *
         * method:切点方法对象
         *
         * objects：切点中参数的集合
         *
         * o:切点所在的类对象
         * */
    
    
        @Override
        public void before(Method method, Object[] objects, Object o) throws Throwable {
    
           // System.out.println(method+"--"+objects[0]+"--"+o);
    
            System.out.println("--前置通知执行--");
    
        }
    }

## **后置通知：（实现AfterReturningAdvice接口）** ##

package com.bjsxt.advice;
    
    import org.springframework.aop.AfterReturningAdvice;
    
    import java.lang.reflect.Method;
    
    public class AfterAdvice implements AfterReturningAdvice {
    
    
        /**
         *  o：切点方法的返回值
         *
         *   method：切点对应的方法对象
         *
         *    objects：切点中的参数类表
         *
         *    o1：切点所在的类对象
         * */
        @Override
        public void afterReturning(Object o, Method method, Object[] objects, Object o1) throws Throwable {
    
            //System.out.println( o+"--"+method+"--"+objects+"--"+o1);
    
            System.out.println("--后置通知执行--");
        }
    }

## 环绕通知：（实现MethodIntecepter接口） ##

package com.bjsxt.advice;
    
    import org.aopalliance.intercept.MethodInterceptor;
    import org.aopalliance.intercept.MethodInvocation;
    
    public class RundAdvice implements MethodInterceptor {
    
        /**
         * methodInvocation
         *      切点对象和切点所在的类的对象
         *
         * */
    
        @Override
        public Object invoke(MethodInvocation methodInvocation) throws Throwable {
    
            System.out.println(methodInvocation);
    
            System.out.println("--环绕通知（前）--");
    
            //执行切点中的目标方法
            Object proceed = methodInvocation.proceed();
    
            System.out.println("--环绕通知（后）--");
    
    
            return proceed;
        }
    }

## 异常通知（出现异常的时候）实现ThrowsAdvice接口 ##

package com.bjsxt.advice;
    
    import org.springframework.aop.ThrowsAdvice;
    
    public class ThrAdvice implements ThrowsAdvice {
    
    
        public void afterThrowing(Exception ex) throws Throwable {
    
            /*
            * Exception ：异常的信息对象
            * */
            System.out.println("异常通知");
    
        }
    }

## **配置xml文件** ##

<?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:tx="http://www.springframework.org/schema/tx"
           xmlns:context="http://www.springframework.org/schema/context"
           xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd
           http://www.springframework.org/schema/aop
           http://www.springframework.org/schema/aop/spring-aop.xsd
           http://www.springframework.org/schema/tx
            http://www.springframework.org/schema/tx/spring-tx.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context.xsd">
    
    
        
    
         <bean id="us" class="com.bjsxt.aop01.User"></bean>
    
    
        
        <bean id="befor" class="com.bjsxt.advice.BeforAdvice"></bean>
    
         
        <bean id="after" class="com.bjsxt.advice.AfterAdvice"></bean>
    
        
        <bean id="rund" class="com.bjsxt.advice.RundAdvice"></bean>
    
        
        <bean id="exp" class="com.bjsxt.advice.ThrAdvice"></bean>
    
    
    
        
        <aop:config>
    
            
            <aop:pointcut id="pt1" expression="execution(* com.bjsxt.aop01.User.b(..))"></aop:pointcut>
    
            <aop:advisor advice-ref="befor" pointcut-ref="pt1"></aop:advisor>
    
            <aop:advisor advice-ref="after" pointcut-ref="pt1"></aop:advisor>
    
            <aop:advisor advice-ref="rund" pointcut-ref="pt1"></aop:advisor>
    
            <aop:advisor advice-ref="exp" pointcut-ref="pt1"></aop:advisor>
    
        </aop:config>
    
    
    </beans>

## 需要添加的方法实体： ##

package com.bjsxt.aop01;
    
    public class User {
        public void a(){
            System.out.println("A");
        }
        public void b(){
            System.out.println("B");
        }
        public void c(){
            System.out.println("C");
        }
    }

## 测试： ##

package com.bjsxt.aop01;
    
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    public class TestA {
        public static void main(String[] args) {
            ClassPathXmlApplicationContext classPathXmlApplicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
            User user = classPathXmlApplicationContext.getBean("user", User.class);
            user.b();
    
        }
    }

## 如果所有的通知都进行添加则执行的顺序是： ##

前置通知

环绕前置通知

方法体

环绕后置通知

后置通知

# #

## 当出现异常时： ##

前置通知

环绕前置通知

异常通知