InetAddress

package test;

import java.io.IOException;
import java.net.InetAddress;

public class Test {  
	  
    public static void main(String[] args) throws IOException {
    	String url="www.baidu.com";//不知为什么加上http://报错
    	InetAddress address=InetAddress.getByName(url);
    	System.out.println("baidu的IP地址：" + address.getHostAddress()) ;
    }
    
   
    /**
     *baidu的IP地址：119.75.217.109
		
     */
}

InetAddress

原文：http://blog.csdn.net/ztt_1119/article/details/46626189