關於Spring的代理問題

1.   設定一個BeanFactory

package com.proxy;import java.io.IOException;import java.io.InputStream;import java.util.Properties;public class BeanFactory { /* * 從設定檔中讀取 */Properties props = new Properties();public BeanFactory(InputStream ips){try {props.load(ips);} catch (IOException e) {e.printStackTrace();}}public Object getBean(String name){String className = props.getProperty(name);Object bean = null;try {Class clazz = Class.forName(className);bean = clazz.newInstance();} catch (Exception e) {e.printStackTrace();} if(bean instanceof ProxyFactoryBean){Object proxy = null;ProxyFactoryBean proxyFactoryBean = (ProxyFactoryBean)bean;try {Advice advice = (Advice)Class.forName(props.getProperty(name + ".advice")).newInstance();Object target = Class.forName(props.getProperty(name + ".target")).newInstance();proxyFactoryBean.setAdvice(advice);proxyFactoryBean.setTarget(target);proxy = proxyFactoryBean.getProxy();} catch (Exception e) {e.printStackTrace();}return proxy;}return bean;}}

2.  設定一個代理工廠 

package com.proxy;import java.lang.reflect.InvocationHandler;import java.lang.reflect.Method;import java.lang.reflect.Proxy;public class ProxyFactoryBean {private Advice advice;private Object target;public Advice getAdvice() {return advice;}public void setAdvice(Advice advice) {this.advice = advice;}public Object getTarget() {return target;}public void setTarget(Object target) {this.target = target;}public Object getProxy() {Object proxy3 = Proxy.newProxyInstance(target.getClass().getClassLoader(),target.getClass().getInterfaces(),new InvocationHandler(){public Object invoke(Object proxy, Method method, Object[] args)throws Throwable {advice.beforeMethod(method);Object retVal = method.invoke(target, args);advice.afterMethod(method);return retVal;}});return proxy3;}}

3.   設定Advice介面

 

package com.proxy;import java.lang.reflect.Method;public  interface Advice { void beforeMethod(Method method); void afterMethod(Method method);}

4. 實現Advice介面 

package com.proxy;import java.lang.reflect.Method;public class MyAdvice implements Advice {long beginTime = 0;public void afterMethod(Method method) {System.out.println("建議前");long endTime = System.currentTimeMillis();System.out.println(method.getName() + " running time of " + (endTime - beginTime));}public void beforeMethod(Method method) {System.out.println("建議後！");beginTime = System.currentTimeMillis();}}

5  寫好一個設定檔 config.properties

#直接指定類#xxx=java.util.ArrayList#指定代理類xxx=com.proxy.ProxyFactoryBeanxxx.advice=com.proxy.MyAdvicexxx.target=java.util.ArrayList

 

6. 寫一個測試類別

package com.proxy;import java.io.InputStream;import java.util.Collection;public class AopFrameworkTest {/**測試是否能夠動態代理 * @param args */public static void main(String[] args) throws Exception {InputStream ips = AopFrameworkTest.class.getResourceAsStream("config.properties");Object bean = new BeanFactory(ips).getBean("xxx");System.out.println(bean.getClass().getName());((Collection)bean).clear();}}