package test.proxy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import junit.framework.TestCase;
public class TestProxy extends TestCase {
protected void setUp() throws Exception {
super.setUp();
}
public void testProxy(){
HelloWorld hw = new HelloWorldImpl();
InvocationHandler handler = new HelloWorldHandler(hw);
HelloWorld proxy = (HelloWorld) Proxy.newProxyInstance(
hw.getClass().getClassLoader(),
hw.getClass().getInterfaces(),
handler);
proxy.sayHelloWorld();
System.out.println();
proxy.setName("liukaiyi");
proxy.getName();
}
}
interface HelloWorld {
void sayHelloWorld() ;
void getName();
void setName(String name);
}
class HelloWorldImpl implements HelloWorld {
private String name = "";
public void setName(String name) {
this.name = name;
}
public void sayHelloWorld() {
System.out.println("Hello World!");
}
public void getName() {
System.out.println(this.name);
}
}
class HelloWorldHandler implements InvocationHandler {
//要代理的原始对象   
            private Object objOriginal;
/**
* 构造函数。
* @param obj 要代理的原始对象。
*/
public HelloWorldHandler(Object obj) {
this.objOriginal = obj ;
}
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
Object result = null ;
String meName = method.getName();
if(meName.indexOf("set")>-1 ){
return method.invoke(this.objOriginal ,args);
}
if( meName.equals("getName") ){
//方法调用之前   
                           doBefore(); //仿佛是AOP的影子，呵呵   
                   }
//调用原始对象的方法   
                           result = method.invoke(this.objOriginal ,args);
//方法调用之后   
                           doAfter();
return result ;
}
private void doBefore() {
System.out.println("before method invoke!");
}
private void doAfter() {
System.out.println("after method invoke!");
}
}