Java IP Address Get getHostIp()

Description

get Host Ip

License

Open Source License

Declaration

public static String getHostIp() 

Method Source Code

//package com.java2s;
/*//w  w w . j  ava2  s .co m
 * Biocep: R-based Platform for Computational e-Science.
 *  
 * Copyright (C) 2007-2009 Karim Chine - karim.chine@m4x.org
 *  
 * Copyright (C) 2007 EMBL-EBI-Microarray Informatics
 *  
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.net.InetAddress;

import java.net.NetworkInterface;

import java.util.Enumeration;

import java.util.Vector;

public class Main {
    public static final String UNKOWN = "Unknown";
    private static String _hostIp = null;

    public static String getHostIp() {
        if (_hostIp == null) {
            try {

                if (System.getProperty("host.ip.forced") != null
                        && !System.getProperty("host.ip.forced").equals("")) {
                    _hostIp = System.getProperty("host.ip.forced");
                } else {
                    //if (isAmazonCloud()) {               
                    //   _hostIp=getAMIHostIp();
                    //} else 
                    {
                        if (publicIPUnavilable()) {
                            String IPAddressFromNetworkInterfaces = getIPAddressFromNetworkInterfaces();
                            if (IPAddressFromNetworkInterfaces != null)
                                _hostIp = IPAddressFromNetworkInterfaces;
                            else
                                _hostIp = "127.0.0.1";
                        } else {
                            _hostIp = InetAddress.getLocalHost().getHostAddress();
                        }
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
                _hostIp = UNKOWN;
            }

            System.out.println("$$$ HOST IP:" + _hostIp);

        }
        return _hostIp;
    }

    public static boolean publicIPUnavilable() {
        try {
            return isLoopBackIP(InetAddress.getLocalHost().getHostAddress());
        } catch (Exception e) {
            e.printStackTrace();
            return true;
        }
    }

    public static String getIPAddressFromNetworkInterfaces() {
        Vector<String> IPs = new Vector<String>();
        try {
            NetworkInterface iface = null;
            for (Enumeration<?> ifaces = NetworkInterface.getNetworkInterfaces(); ifaces.hasMoreElements();) {
                iface = (NetworkInterface) ifaces.nextElement();
                InetAddress ia = null;
                for (Enumeration<?> ips = iface.getInetAddresses(); ips.hasMoreElements();) {
                    ia = (InetAddress) ips.nextElement();
                    boolean matches = isValidIPAddress(ia.getHostAddress()) && !isLoopBackIP(ia.getHostAddress());
                    if (matches) {
                        IPs.add(ia.getHostAddress());
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        if (IPs.size() == 1)
            return IPs.elementAt(0);
        return null;
    }

    public static boolean isLoopBackIP(String ipAddress) {
        return ipAddress.startsWith("127.");
    }

    public static boolean isValidIPAddress(String ipAddress) {
        String[] parts = ipAddress.split("\\.");
        if (parts.length != 4) {
            return false;
        }
        for (String s : parts) {
            int i = Integer.parseInt(s);
            if ((i < 0) || (i > 255)) {
                return false;
            }
        }
        return true;
    }
}

Related

1. getFirstLocalNonLoopbackIpAddress()
2. getFirstNonLoopbackAddress(boolean preferIpv4, boolean preferIPv6)
3. getFirstNonLoopBackAddress(boolean preferIpv4, boolean preferIPv6)
4. getHostIp()
5. getHostIP()
6. getHostIP()
7. getHostIP()
8. getHostIpAddress()
9. getHostIPByHostName(String host)