java 代理模式（静态代理+动态代理）

静态代理：

ISubject：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午1:49:29
*/
public interface ISubject {
public void request();
}

RealSubject（真实角色）：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午1:51:37
*/
public class RealSubject implements ISubject{

@Override
public void request() {
System.out.println("realSubject requesting");
}
}

ProxySubject（代理类）：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午1:52:22
*/
public class ProxySubject implements ISubject{
private RealSubject realSubject;
public ProxySubject() {
realSubject = new RealSubject();
}

@Override
public void request() {
System.out.println("do something before");
realSubject.request();
System.out.println("do something after");
}
}

Test（客户端测试）:

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午1:54:47
*/
public class Test {
public static void main(String[] args) {
ISubject proxySubject = new ProxySubject();
proxySubject.request();
}
}

------------------------------------------------------------------------------------------------------------------------------

动态代理：

ISubject：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午2:51:31
*/
public interface ISubject {
public void request();
}

RealSubject：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午2:52:00
*/
public class RealSubject implements ISubject{

@Override
public void request() {
System.out.println("realSubject requesting");
}
}

SubjectInvocationHandler（调用处理类）：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午2:54:38
* 调用处理类
*/
public class SubjectInvocationHandler implements InvocationHandler{
private Object obj;

public SubjectInvocationHandler(Object obj) {
this.obj = obj;
}

/**
* 生成代理类工厂
* @author com.tiantian
* @param realObj
* @return 返回生成的代理类
*/
public static Object getProxyInstanceFactory(Object realObj){
Class<?> classType = realObj.getClass();
return Proxy.newProxyInstance(classType.getClassLoader(),
classType.getInterfaces(), new SubjectInvocationHandler(realObj));
}

@Override
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
System.out.println("before");

method.invoke(obj, args);

System.out.println("after");

return null;
}
}

Test：

/**
* @author com.tiantian
* @version 创建时间：2012-11-20 下午2:56:25
*/
public class Test {
public static void main(String[] args) {
RealSubject realSubject = new RealSubject();
//        InvocationHandler handler = new SubjectInvocationHandler(realSubject);
//        ISubject subject = (ISubject)Proxy.newProxyInstance(realSubject.getClass().getClassLoader(),
//                realSubject.getClass().getInterfaces(), handler);
ISubject subject = (ISubject)SubjectInvocationHandler.getProxyInstanceFactory(realSubject);
subject.request();

}
}