title: Detecting all available network's broadcast addresses in Java
body: <p>For my project I wanted to get a list of all available broadcast addresses so I could broadcast a request and my other application located on other computer in the unspecified network would respond and to get the list I (now using little modified version with contribution of Mike) came up with this:</p>
  
  <pre>
  <code>
  private ArrayList&lt;InetAddress> getBroadcastAddresses() {
          ArrayList&lt;InetAddress> listOfBroadcasts = new ArrayList();
          Enumeration list;
          try {
              list = NetworkInterface.getNetworkInterfaces();
  
              while(list.hasMoreElements()) {
                  NetworkInterface iface = (NetworkInterface) list.nextElement();
  
                  if(iface == null) continue;
  
                  if(!iface.isLoopback() && iface.isUp()) {
                      System.out.println("Found non-loopback, up interface:" + iface);
  
                      Iterator it = iface.getInterfaceAddresses().iterator();
                      while (it.hasNext()) {
                          InterfaceAddress address = (InterfaceAddress) it.next();
  
                          System.out.println("Found address: " + address);
  
                          if(address == null) continue;
                          InetAddress broadcast = address.getBroadcast();
                          if(broadcast != null) listOfBroadcasts.add(broadcast);
                      }
                  }
              }
          } catch (SocketException ex) {
              return new ArrayList&lt;InetAddress>();
          }
  
          return site;
  }
  </code>
  </pre>
  
  <p>It works quite well for reqular LAN however when it comes to the WiFi LAN it just skips the second while loop after one step because of having <code>address</code> equals null even though when I used <code>System.out.println(interfaceItem)</code> just to view what interfaces are being gone through it wrote wireless LAN's name and my IP corresponding to the network.</p>
  
  <p><b>EDIT 1:</b>
  <a href="http://aetips.wz.cz/output.txt" rel="noreferrer">This</a> is the output where 172.16.1.104 is my IP in the wireless network. The problem appears ONLY on my notebook with Wifi. The output is from my notebook where I mostly use wireless and sometimes I use UTP to connect with my friend. There is also one network interface of VirtualBox on my notebook.</p>
  
  <p>Could you tell me what's wrong with it? Thank you!</p>
  
  <p><i>Note: So it turns out that this might be problem for my notebook in particular and the code works for everybody else in general, I love this kind of problem :-) Seems like a dead end to me but thank for help anyway :-)<br><br>Still love you! ;-)</i></p>