Java代理类Proxy

import java.lang.reflect.*;
import java.util.*;

public class ProxyTest
{
	public static void main(String[] args)
	{
		Object[] elements = new Object[1000];
		
		//fill elements with proxies for the integers 1...1000
		for(int i=0; i<elements.length; i++)
		{
			Integer value = i+1;
			Class[] interfaces = value.getClass().getInterfaces();
			InvocationHandler handler = new TraceHandler(value);
			Object proxy = Proxy.newProxyInstance(null, interfaces, handler);
			elements[i] = proxy;
		}
		
		//construct a random integer
		Integer key = new Random().nextInt(elements.length) + 1;
		
		//search for the key
		int result = Arrays.binarySearch(elements, key);
		
		//print match if found
		if(result >= 0)
			System.out.println(elements[result]);
			
	}
}

class TraceHandler implements InvocationHandler
{
	public TraceHandler(Object t)
	{
		target = t;
	}
	
	public Object invoke(Object proxy, Method m, Object[] args) throws Throwable
	{
		//print implicit argument
		System.out.print(target);
		//print method name
		System.out.print("."+m.getName()+"(");
		//print explicit arguments
		if(args != null)
		{
			for(int i=0; i<args.length; i++)
			{
				System.out.print(args[i]);
				if(i < args.length-1)
					System.out.print(", ");
			}
		}
		System.out.println(")");
		
		//invoke actual method
		return m.invoke(target, args);
	}
	
	private Object target;
}