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PODetecting all available network's broadcast addresses in Java
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  1. PODetecting all available network's broadcast addresses in Java
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    copied!<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>
 

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