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Java實(shí)現(xiàn)AOP功能的封裝與配置的小框架實(shí)例代碼

更新時(shí)間：2018年02月06日 14:14:42 作者：brianway

這篇文章主要介紹了Java實(shí)現(xiàn)AOP功能的封裝與配置的小框架實(shí)例代碼，分享了相關(guān)代碼示例，小編覺(jué)得還是挺不錯(cuò)的，具有一定借鑒價(jià)值，需要的朋友可以參考下

本文通過(guò)是動(dòng)態(tài)代理實(shí)現(xiàn)的AOP功能的封裝與配置的小框架.加深對(duì)動(dòng)態(tài)代理和AOP編程的理解

設(shè)計(jì)

根據(jù)配置文件的鍵xxx對(duì)應(yīng)的值(類全名)創(chuàng)建相應(yīng)類的對(duì)象。

當(dāng)且僅當(dāng)xxx對(duì)應(yīng)的值為com.iot.proxy.aopframework.ProxyFactoryBean時(shí)，則生成相應(yīng)的動(dòng)態(tài)代理類對(duì)象。代理對(duì)象的目標(biāo)類和通知實(shí)現(xiàn)類分別由xxx.target和xxx.advice配置

配置文件

config.propertiest位于aopframework包下

xxx代表要加載的類
xxx.advice代表通知接口的某個(gè)實(shí)現(xiàn)類
xxx.target代表委托類

#xxx=java.util.ArrayList
xxx=com.iot.proxy.aopframework.ProxyFactoryBean
xxx.advice=com.iot.proxy.MyAdvice
xxx.target=java.util.ArrayList

包:com.iot.proxy.aopframework,有如下幾個(gè)類/接口：

BeanFactory,用于讀取配置文件，根據(jù)配置創(chuàng)建相應(yīng)的對(duì)象
ProxyFactoryBean,用于生成代理對(duì)象，含有兩個(gè)私有屬性:目標(biāo)和通知
Advice,通知接口，用于把切面的代碼以對(duì)象的形式傳遞給InvocationHandler的的invoke方法
MyAdvice,Advice接口的一個(gè)實(shí)現(xiàn)類，打印執(zhí)行方法前的時(shí)間及執(zhí)行耗時(shí)
AopFrameWorkTest，測(cè)試效果

代碼

Advice接口

package com.iot.proxy.aopframework;

import java.lang.reflect.Method;
/**
 * Created by brian on 2016/2/2.
 */
public interface Advice {
  void beforeMethod(Method method);
  void aftereMethod(Method method);
}

MyAdvice類

package com.iot.proxy.aopframework;
import java.lang.reflect.Method;
/**
 * Created by brian on 2016/2/2.
 */
public class MyAdvice implements Advice{
	long beginTime = 0 ;
	@Override
	  public void beforeMethod(Method method) {
		System.out.println(method.getName()+" before at "+beginTime);
		beginTime = System.currentTimeMillis();
	}
	@Override
	  public void aftereMethod(Method method) {
		long endTime = System.currentTimeMillis();
		System.out.println(method.getName()+" cost total "+ (endTime-beginTime));
	}
}

BeanFactory類

package com.iot.proxy.aopframework;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
/**
 * Created by brian on 2016/2/2.
 */
public class BeanFactory {
	Properties properties = new Properties();
	public BeanFactory(InputStream inputStream){
		try {
			properties.load(inputStream);
		}
		catch (IOException e) {
			e.printStackTrace();
		}
	}
	public Object getBean(String name){
		String className = properties.getProperty(name);
		Object bean = null;
		try {
			Class clazz = Class.forName(className);
			bean = clazz.newInstance();
		}
		catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
		catch (InstantiationException e) {
			e.printStackTrace();
		}
		catch (IllegalAccessException e) {
			e.printStackTrace();
		}
		if (bean instanceof ProxyFactoryBean){
			ProxyFactoryBean proxyFactoryBean = (ProxyFactoryBean)bean;
			Advice advice = null;
			Object target = null;
			try {
				advice = (Advice) Class.forName(properties.getProperty(name+".advice")).newInstance();
				target = Class.forName(properties.getProperty(name+".target")).newInstance();
			}
			catch (InstantiationException e) {
				e.printStackTrace();
			}
			catch (IllegalAccessException e) {
				e.printStackTrace();
			}
			catch (ClassNotFoundException e) {
				e.printStackTrace();
			}
			proxyFactoryBean.setAdvice(advice);
			proxyFactoryBean.setTarget(target);
			Object proxy = ((ProxyFactoryBean) bean).getProxy();
			return proxy;
		}
		return bean;
	}
}

ProxyFactoryBean類

package com.iot.proxy.aopframework;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
/**
 * Created by brian on 2016/2/3.
 */
public class ProxyFactoryBean {
	private Object target;
	private Advice advice;
	public Object getProxy(){
		Object proxy = Proxy.newProxyInstance(
		        target.getClass().getClassLoader(),
		        target.getClass().getInterfaces(),
		        new InvocationHandler() {
			@Override
			          public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
				advice.beforeMethod(method);
				Object retVal = method.invoke(target,args);
				advice.aftereMethod(method);
				return retVal;
			}
		}
		);
		return proxy;
	}
	public Object getTarget() {
		return target;
	}
	public void setTarget(Object target) {
		this.target = target;
	}
	public Advice getAdvice() {
		return advice;
	}
	public void setAdvice(Advice advice) {
		this.advice = advice;
	}
}

AopFrameWorkTest類

package com.iot.proxy.aopframework;
import java.io.InputStream;
import java.util.Collection;
/**
 * Created by brian on 2016/2/3.
 */
public class AopFrameWorkTest {
	public static void main(String[] args) {
		InputStream inputStream = AopFrameWorkTest.class.getResourceAsStream("config.properties");
		Object bean = new BeanFactory(inputStream).getBean("xxx");
		System.out.println(bean.getClass().getName());
		((Collection) bean).clear();
	}
}