Java Broadcast Address Get getBroadcastAddresses()

Description

FROM edu.nps.moves.examples.EspduSender A number of sites get all snippy about using 255.255.255.255 for a bcast address; it trips their security software and they kick you off their network.

License

Open Source License

Return

set of all bcast addresses

Declaration

public static Set<InetAddress> getBroadcastAddresses()

Method Source Code


//package com.java2s;
//License from project: Open Source License 

import java.net.*;
import java.util.*;

public class Main {
    /**/*www  .  ja  v  a 2  s . com*/
     * FROM edu.nps.moves.examples.EspduSender
     * 
     * A number of sites get all snippy about using 255.255.255.255 for a bcast
     * address; it trips their security software and they kick you off their 
     * network. (Comcast, NPS.) This determines the bcast address for all
     * connected interfaces, based on the IP and subnet mask. If you have
     * a dual-homed host it will return a bcast address for both. If you have
     * some VMs running on your host this will pick up the addresses for those
     * as well--eg running VMWare on your laptop with a local IP this will
     * also pick up a 192.168 address assigned to the VM by the host OS.
     * 
     * @return set of all bcast addresses
     */
    public static Set<InetAddress> getBroadcastAddresses() {
        Set<InetAddress> bcastAddresses = new HashSet<InetAddress>();
        Enumeration<NetworkInterface> interfaces;

        try {
            interfaces = NetworkInterface.getNetworkInterfaces();

            while (interfaces.hasMoreElements()) {
                NetworkInterface anInterface = (NetworkInterface) interfaces.nextElement();

                if (anInterface.isUp()) {
                    Iterator<InterfaceAddress> it = anInterface.getInterfaceAddresses().iterator();
                    while (it.hasNext()) {
                        InterfaceAddress anAddress = (InterfaceAddress) it.next();
                        if ((anAddress == null || anAddress.getAddress().isLinkLocalAddress()))
                            continue;

                        //System.out.println("Getting bcast address for " + anAddress);
                        InetAddress abcast = anAddress.getBroadcast();
                        if (abcast != null)
                            bcastAddresses.add(abcast);
                    }
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }

        return bcastAddresses;
    }
}