Java InetAddress Create getInetAddress(String str)

Description

get Inet Address

License

Open Source License

Declaration

private static InetAddress getInetAddress(String str) 

Method Source Code

//package com.java2s;
/*//  w ww  . j  ava2 s .  c o m
 * Copyright 2012-2013 James Geboski <jgeboski@gmail.com>
 *
 * 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.UnknownHostException;
import java.util.Arrays;

public class Main {
    private static InetAddress getInetAddress(String str) {
        byte addr[];

        addr = getNumericAddress4(str);

        if (addr == null)
            addr = getNumericAddress6(str);

        if (addr == null)
            return null;

        try {
            return InetAddress.getByAddress(new String(), addr);
        } catch (UnknownHostException e) {
            return null;
        }
    }

    private static byte[] getNumericAddress4(String str) {
        String ss[];
        byte bs[];
        int i;
        int v;

        ss = str.split("\\.");

        if (ss.length != 4)
            return null;

        bs = new byte[4];

        try {
            for (i = 0; i < bs.length; i++) {
                v = Integer.parseInt(ss[i]);

                if ((v < 0) || (v > 255))
                    return null;

                bs[i] = (byte) v;
            }
        } catch (NumberFormatException e) {
            return null;
        }

        return bs;
    }

    private static byte[] getNumericAddress6(String str) {
        char cs[];
        byte bs[];
        int i;
        int c;
        int o;
        int val;
        int vch;

        boolean cold;

        cs = str.toCharArray();
        bs = new byte[16];
        cold = false;
        val = i = c = 0;

        if ((cs[0] == ':') && (cs[1] != ':'))
            return null;

        while ((i < cs.length) && (c < bs.length)) {
            if (cs[i] == ':') {
                cold = true;

                if (++i >= cs.length)
                    return null;

                if (cs[i] != ':')
                    continue;

                if (++i >= cs.length)
                    return bs;

                o = i - 1;
                c += bs.length - (c + 2);

                while ((o = Arrays.binarySearch(cs, ++o, cs.length, ':')) >= 0)
                    c += 2;

                if (c >= bs.length)
                    return null;
            }

            while (i < cs.length) {
                vch = Character.digit(cs[i], 16);

                if (vch < 0) {
                    if (cs[i] == ':')
                        break;

                    return null;
                }

                val <<= 4;
                val |= (byte) vch;
                i++;
            }

            if (val > 0xFFFF)
                return null;

            bs[c++] = (byte) ((val >> 8) & 0xFF);
            bs[c++] = (byte) (val & 0xFF);
            val = 0;
        }

        return cold ? bs : null;
    }
}

Related

1. getInetAddress(Socket socket)
2. getInetAddress(String dottedNotation)
3. getInetAddress(String host)
4. getInetAddress(String hostName)
5. getInetAddress(String name)
6. getInetAddressByName(String name)
7. getInetAddresses()
8. getInetAddresses(String filter)
9. getInetAddressFor(final Inet6Address inetAddress, String scope)