Java Local Host Get getLocalHostAddress()

Description

Returns the real IP Address of the NIC for the localhost.

License

Apache License

Exception

Parameter	Description
RuntimeException	If unable to resolve address

Return

String representation of IP Address

Declaration

public static String getLocalHostAddress() throws RuntimeException 

Method Source Code

//package com.java2s;
/*/*from  ww w .ja va2 s  .  co m*/
 * Copyright (C) 2008 Yohan Liyanage. 
 * 
 * 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.InetAddress;
import java.net.UnknownHostException;

public class Main {
    /**
     * Returns the real IP Address of the NIC for the localhost.
     * 
     * @return String representation of IP Address
     * 
     * @throws RuntimeException If unable to resolve address
     */
    public static String getLocalHostAddress() throws RuntimeException {
        try {
            return InetAddress.getLocalHost().getHostAddress();
        } catch (UnknownHostException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Returns the Host Address (IP Address) of the given 
     * URL. This method uses {@link InetAddress#getByName(String)}
     * to detect the IP Address of the given host.
     * 
     * @param url URL as a String
     * @return Host Address as String
     */
    public static String getHostAddress(String url) throws UnknownHostException {

        // Split from :// and : and get Host Name Part
        String hostAddress = url.split("://")[1].split(":")[0];

        // For localhost loopback, detect real network name
        if (hostAddress.equals("localhost") || hostAddress.equals("127.0.0.1")) {

            // Local Address : Find Real Network IP
            hostAddress = InetAddress.getLocalHost().getHostAddress();

        } else {
            // Find IP Address
            hostAddress = InetAddress.getByName(hostAddress).getHostAddress();
        }

        return hostAddress;
    }
}

Related

1. getLocalHost()
2. getLocalHost()
3. getLocalHost()
4. getLocalHost()
5. getLocalHost()
6. getLocalHostAddress()
7. getLocalhostAddress()
8. getLocalHostID()
9. getLocalHostLANAddress()