Publish and stop endpoint web service in Java

Question

I am trying to start/stop an Endpoint web service in a separate thread from my main program with the click of a button. Starting works fine, i am able to access all my WebMethods without issue. The problem is, when i click the stop button to try and stop the web service endpoint, i get an exception and i don't know what it is. I am new to Java as well.

Thanks in advance.

Excetion thrown at 'ep.stop()':

WebService Running On: http://0.0.0.0:9898/

        Exception in thread "Thread-0" java.lang.NullPointerException
            at com.sun.xml.internal.ws.transport.http.server.ServerMgr.removeContext(Unknown Source)
            at com.sun.xml.internal.ws.transport.http.server.HttpEndpoint.stop(Unknown Source)
            at com.sun.xml.internal.ws.transport.http.server.EndpointImpl.stop(Unknown Source)
            at com.simba.Server.startWebSrv(Server.java:27)
            at com.simba.Server.run(Server.java:13)

Server class:

import javax.xml.ws.Endpoint;

public class Server extends Thread {

      public volatile boolean active = true;
      private Endpoint ep; 
      private String ip = "0.0.0.0";

      public void run(){
            ep = Endpoint.publish("http://" + ip + ":9898/",  new SWS());
            startWebSrv();
      }

      private void startWebSrv(){
          synchronized(this){
              try {
                  while (active) {
                      System.out.println("WebService Running On: http://" + ip + ":9898/");
                      wait();
                  }
              }catch (InterruptedException e) {
                  e.printStackTrace();
              }finally{
                if(!active){
                    ep.stop();
                    System.out.println("WebService Stopped!");
                }
              }
          }
      }
}

How i am attempting to stop the service/thread from my main program:

MenuItem mntmToggleWebservice = new MenuItem(menu_4, SWT.NONE);
        mntmToggleWebservice.addSelectionListener(new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                synchronized(srv){
                    srv.active = false;
                    srv.notifyAll();            
                }
            }
        });
        mntmToggleWebservice.setText("Toggle WebService");

Answer 1

Problem solved!

Don't use '0.0.0.0'. For some reason, creating the service on '0.0.0.0' works (uses the machine's actual ip), but Endpoint.stop() doesn't not play well with it.

Instead I just used 'System.getEvn('COMPUTERNAME')' and create the service with the machine name.