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內容java基礎鞏固筆記 - 實現AOP功能的封裝與配置的小框架設計（目錄）：XXX = java.util.ArrayList中代碼Advice介面MyAdvice類BeanFactory類ProxyFactoryBean類AopFrameWorkTest類輸出本文通過是動態代理實現的AOP功能的封裝與配置的小框架.加深對動態代理和AOP編程的理解設計根據配置文件的鍵xxx對應的值(類全名)創建相應類的對象。當且僅當xxx對應的值為com.iot.proxy.aopframework.ProxyFactoryBean時，則生成相應的動態代理類對象。代理對象的目標類和通知實現類分別由xxx.target和xxx.advice配置配置文件config.propertiest位於aopframework包下xxx代表要載入的類xxx.advice代表通知介面的某個實現類xxx.target代表委託類#xxx=java.util.ArrayListxxx=com.iot.proxy.aopframework.ProxyFactoryBeanxxx.advice=com.iot.proxy.MyAdvicexxx.target=java.util.ArrayList包:com.iot.proxy.aopframework,有如下幾個類/介面：BeanFactory,用於讀取配置文件，根據配置創建相應的對象ProxyFactoryBean,用於生成代理對象，含有兩個私有屬性:目標和通知Advice,通知介面，用於把切面的代碼以對象的形式傳遞給InvocationHandler的的invoke方法MyAdvice,Advice介面的一個實現類，列印執行方法前的時間及執行耗時AopFrameWorkTest，測試效果代碼Advice介面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 ;@Overridepublic void beforeMethod(Method method) {System.out.println(method.getName+" before at "+beginTime);beginTime = System.currentTimeMillis;}@Overridepublic 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 {@Overridepublic 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;}}輸出配置xxx=com.iot.proxy.aopframework.ProxyFactoryBean輸出為：com.sun.proxy.$Proxy0clear before at 0clear cost total 0配置xxx=java.util.ArrayList輸出為：java.util.ArrayList可以看出，只改變配置文件，就可改變代碼的運行結果，從而達到靈活的效果