Databases
StackOverflow2013
Postsdbo
POJava Multicast doesnt work in windows
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POJava Multicast doesnt work in windows
    primarykey
    data
    text
    <p>I have this code but it doens't work in 2 diferent computers, I changed my firewall but it doesnt work.</p> <pre><code>import java.io.IOException; import java.lang.management.ManagementFactory; import java.net.DatagramPacket; import java.net.InetAddress; import java.net.MulticastSocket; import java.rmi.RMISecurityManager; import java.util.ArrayList; import java.util.HashMap; public class TestingDota{ private static String name; public static void main(String args[]){ name = args[0]; final InetAddress group; final String address = "230.0.0.1"; final int port = 9876; try{ group = InetAddress.getByName(address); }catch(Exception e){ e.printStackTrace(); return; } HashMap&lt;String, Tupla&gt; map = new HashMap&lt;String,Tupla&gt;(); try{ final MulticastSocket socket = new MulticastSocket(port); socket.setReuseAddress(true); socket.joinGroup(group); socket.setTimeToLive(2); new Thread(){ public void run(){ while(true){ String msg = ManagementFactory.getRuntimeMXBean().getName()+ "," + name; DatagramPacket packet = new DatagramPacket(msg.getBytes(), msg.length(), group, port); try { socket.send(packet); Thread.sleep(1000); } catch (IOException e){ e.printStackTrace(); } catch (InterruptedException e) { e.printStackTrace(); } } } }.start(); while(true){ byte[] buf = new byte[512]; DatagramPacket packet = new DatagramPacket(buf, buf.length); socket.receive(packet); String msg = new String(packet.getData()).trim(); int index = msg.indexOf(','); String key = msg.substring(0,index); String name = msg.substring(index+1, msg.length()); long time = System.currentTimeMillis(); if(map.containsKey(key)){ Tupla t = map.get(key); t.time = time; }else{ Tupla t = new Tupla(); t.name = name; t.time = time; map.put(key, t); mostrar(map); } int size = map.size(); ArrayList&lt;String&gt; list = new ArrayList&lt;String&gt;(); for(String k : map.keySet()){ Tupla t = map.get(k); if(time - t.time&gt; 1500 ){ list.add(k); } } for(String x : list) map.remove(x); if(size &gt; map.size()){ mostrar(map); } Thread.sleep(100); } }catch(Exception e){ e.printStackTrace(); } } private static void mostrar(HashMap&lt;String, Tupla&gt; map) { for(String k : map.keySet()){ Tupla t = map.get(k); System.out.println(t.name); } System.out.println(); } static class Tupla{ String name; long time; } } </code></pre> <p>To run this program please write: $ java TestingDota someName, it works with several terminals in the same computer, but it doesnt work in diferent computers</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USuser207421
    1. USuser1351870
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COIt could be your router. AFAIK, most home routers, and even some enterprise-class routers do not implement IP Multicast.
      singulars
      1. POJava Multicast doesnt work in windows
      1. USGreyBeardedGeek
    2. COCalling setReuseAddress() after you have already bound the socket to the port accomplishes precisely nothing.
      singulars
      1. POJava Multicast doesnt work in windows
      1. USuser207421
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload