Java InetAddress Create getFQDN(final InetAddress addr)

Description

get FQDN

License

Apache License

Declaration

public static String getFQDN(final InetAddress addr) 

Method Source Code

//package com.java2s;
/*//from  w  w w  .j av  a 2 s .  c o m
 * @(#)$Id$$
 *
 * Copyright 2006-2008 Makoto YUI
 *
 * 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.
 * 
 * Contributors:
 *     Makoto YUI - initial implementation
 */

import java.net.*;

public class Main {
    public static String getFQDN(final InetAddress addr) {
        String hostname = addr.getHostName();
        if (hostname.indexOf('.') >= 0) {
            return hostname;
        }
        hostname = addr.getCanonicalHostName();
        if (hostname.indexOf('.') >= 0) {
            return hostname;
        }
        String hostAddr = addr.getHostAddress();
        try {
            return InetAddress.getByName(hostAddr).getHostName();
        } catch (UnknownHostException e) {
            return hostAddr;
        }
    }
}

Related

1. getBytes(InetAddress addr, int port)
2. getClassPart(InetAddress ip, int partNumber)
3. getConnectionAddress(InetAddress addr)
4. getDestinationInetAddress(URI uri)
5. getExternalAddresses(InetAddress[] addresses)
6. getFreePort(InetAddress ipAddress)
7. getFreeSocket(InetAddress bindAddress, int portRangeStart, int portRangeEnd)
8. getFreeTCPPort(InetAddress ipAddress)
9. getFullHostName(InetAddress netAddress)