package com.cn.spring.aop.impl;//加减乘除的接口类public interface ArithmeticCalculator {    int add(int i, int j);    int sub(int i, int j);    int mul(int i, int j);    int div(int i, int j);}

package com.cn.spring.aop.impl;import org.springframework.stereotype.Component;//实现类@Componentpublic class ArithmeticCalculatorImpl implements ArithmeticCalculator {    @Override    public int add(int i, int j) {        int result = i + j;        return result;    }    @Override    public int sub(int i, int j) {        int result = i - j;        return result;    }    @Override    public int mul(int i, int j) {        int result = i * j;        return result;    }    @Override    public int div(int i, int j) {        int result = i / j;        return result;    }}

<?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="com.cn.spring.aop.impl">    </context:component-scan>    <!--使AspjectJ注解起作用：自动为匹配的类生成代理对象-->    <aop:aspectj-autoproxy></aop:aspectj-autoproxy></beans>

package com.cn.spring.aop.impl;import org.aspectj.lang.JoinPoint;import org.aspectj.lang.ProceedingJoinPoint;import org.aspectj.lang.annotation.After;import org.aspectj.lang.annotation.AfterReturning;import org.aspectj.lang.annotation.AfterThrowing;import org.aspectj.lang.annotation.Aspect;import org.aspectj.lang.annotation.Before;import org.springframework.stereotype.Component;import java.util.Arrays;import java.util.List;//把这个类声明为一个切面：首先需要把该类放入到IOC容器中，在声明为一个切面@Aspect@Componentpublic class LoggingAspect {

@Pointcut("execution(** ArithmeticCalculator.*(..))")
public void declareJointPointExpression(){

}
//声明该方法是一个前置通知：在目标方法开始之前执行
//@Before("execution(public int ArithmeticCalculator.*(int, int))")


//前置通知
@Before("declareJointPointExpression()")
public void beforeMethod(JoinPoint joinPoint) {
String methodName = joinPoint.getSignature().getName();
List<Object> args = Arrays.asList(joinPoint.getArgs());
Object target = joinPoint.getTarget();
System.out.println("The method " + methodName + " begins with " + args + target);
}

//后置通知    @After("execution(** ArithmeticCalculator.*(int, int))")    public void afterMethod(JoinPoint joinPoint){        String methodName = joinPoint.getSignature().getName();         System.out.println("The method " +  methodName + " ends ");    }    //返回通知，在方法正常结束后执行的方法，可以访问到方法的返回值    @AfterReturning(value=http://www.mamicode.com/"execution(** ArithmeticCalculator.*(int, int))",            returning = "result")    public void afterReturning(JoinPoint joinPoint , Object result){        String methodName = joinPoint.getSignature().getName();                 System.out.println("The method " +  methodName + " ends with " + result);    }    //异常通知    @AfterThrowing(value=http://www.mamicode.com/"execution(** ArithmeticCalculator.*(int, int))",            throwing = "ex")    public void afterThrowing(Exception ex){                System.out.println(ex);    }    }/* * JoinPoint访问到连接点上下文的信息 * JoinPoint ?             java.lang.Object[] getArgs()：获取连接点方法运行时的入参列表； ?             Signature getSignature() ：获取连接点的方法签名对象； ?             java.lang.Object getTarget() ：获取连接点所在的目标对象； ?              java.lang.Object getThis() ：获取代理对象本身；  * */

//功能最强大的环绕通知    //ProceedingJoinPoint 类型的参数可以决定是否执行目标方法    @Around("execution(** ArithmeticCalculator.*(..))")    public Object aroundMethod(ProceedingJoinPoint pjd){        Object result = null ;        String methodName = pjd.getSignature().getName();                try {            System.out.println("before");            result = pjd.proceed();            System.out.println("after " + result);        } catch (Throwable e) {            // TODO Auto-generated catch block            e.printStackTrace();            System.out.println("Exception " + e);        }        System.out.println("return " + result);        return result;    }