Spring学习之旅（七）基于XML配置与基于AspectJ注解配置的AOP编程比较

package com.edu.aop;

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.edu.aop;

public class ArithmeticCalculatorImpl implements ArithmeticCalculator {

    @Override
    public int add(int i, int j) {
        return i+j;
    }

    @Override
    public int sub(int i, int j) {
        return i-j;
    }

    @Override
    public int mul(int i, int j) {
        return i*j;
    }

    @Override
    public int div(int i, int j) {
        return i/j;
    }

}

package com.edu.aop;

import java.util.Arrays;

import org.aspectj.lang.JoinPoint;

public class LoggingAspect {
/**
 * 日志切面类
 */
    
    public void beforeMethod(JoinPoint joinPoint){
        //获取方法名
        String methodName=joinPoint.getSignature().getName();
        //获取方法实参值列表
        Object[] args=joinPoint.getArgs();
        System.out.println("The method "+methodName+" begin with "+Arrays.asList(args));
    }
    
    public void afterMethod(JoinPoint joinPoint){
        String methodName=joinPoint.getSignature().getName();
        System.out.println("The method "+methodName+" ends");
    }
}

package com.edu.aop;

import java.util.Arrays;

import org.aspectj.lang.JoinPoint;

public class ValidationAspect {

    public void validationArgs(JoinPoint joinPoint){
        String methodName=joinPoint.getSignature().getName();
        Object[] args=joinPoint.getArgs();
        System.out.println("待验证参数："+Arrays.asList(args));
        if(args!=null&&args.length>0){
            for(int i=0;i<args.length;++i){
                if(((Integer)args[i]).intValue()<0){
                    System.out.println("警告：方法"+methodName+"()第"+(i+1)+"个参数为负数："+args[i]);
                }
            }
        }
    }
}

<?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"
    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">

<!-- 配置bean -->
<bean id="arithmetic" class="com.edu.aop.ArithmeticCalculatorImpl"></bean>

<!-- 分别将切面类声明配置成一个bean -->
<bean id="logging" class="com.edu.aop.LoggingAspect"></bean>
<bean id="validation" class="com.edu.aop.ValidationAspect"></bean>

<aop:config>
<!-- 配置日志切片类 -->
<aop:aspect ref="logging">
<!-- 配置前置通知 及前置通知的切入点-->
<aop:before method="beforeMethod" pointcut="execution(* com.edu.aop.ArithmeticCalculatorImpl.*(..))"></aop:before>
<!-- 配置后置通知及后置通知的切入点 -->
<aop:after method="afterMethod" pointcut="execution(* com.edu.aop.ArithmeticCalculatorImpl.*(..))"></aop:after>
</aop:aspect>

<!-- 配置检测参数切片类 -->
<aop:aspect ref="validation">
<!-- 配置前置通知 及前置通知的切入点-->
<aop:before method="validationArgs" pointcut="execution(* com.edu.aop.ArithmeticCalculatorImpl.*(..))"></aop:before>
</aop:aspect>
</aop:config>
</beans>

package com.edu.aop;

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

public class Main {

    public static void main(String[] args) {

        ApplicationContext act=new ClassPathXmlApplicationContext("applicationContext.xml");
        ArithmeticCalculator arithmetic=(ArithmeticCalculator)act.getBean("arithmetic");
        int result=arithmetic.add(10, 20);
        System.out.println("result:"+result);
        result=arithmetic.div(-36, 4);
        System.out.println("result:"+result);
    }

}