Here you can find the source of getHostAddress()
public static String getHostAddress() throws SocketException, UnknownHostException
//package com.java2s; /**//from ww w . j a v a2 s . c o m * Copyright (C) 2014-2015 LinkedIn Corp. (pinot-core@linkedin.com) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.net.DatagramSocket; import java.net.InetAddress; import java.net.SocketException; import java.net.UnknownHostException; public class Main { private static final String DUMMY_OUT_IP = "74.125.224.0"; /** * Get the ip address of local host. */ public static String getHostAddress() throws SocketException, UnknownHostException { DatagramSocket ds = new DatagramSocket(); ds.connect(InetAddress.getByName(DUMMY_OUT_IP), 80); InetAddress localAddress = ds.getLocalAddress(); if (localAddress.getHostAddress().equals("0.0.0.0")) { localAddress = InetAddress.getLocalHost(); } return localAddress.getHostAddress(); } }