java得到返回重定向地址

package com.webkfa.test;

import java.net.HttpURLConnection;
import java.net.URL;
public class Test {
	/**
	 * 返回重定向地址
	 * @param url
	 * @return
	 */
	public static String urlto320url(String url){
		String tempstr=url;
		HttpURLConnection conn=null;
		try{
			URL durl = new URL(url);
			conn = (HttpURLConnection) durl.openConnection();
			tempstr=conn.getURL().toString();
			durl = new URL(url);
			conn = (HttpURLConnection) durl.openConnection();
			tempstr=conn.getURL().toString();
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			if(conn!=null)conn.disconnect();
		}
		System.out.println(tempstr);
		return tempstr;
	}
	public static void main(String[] args){
		//要自己把http://www.webkfa.com换成有302的地十
		String url=urlto320url("http://www.webkfa.com");
		System.out.println(url);
	}
}