Program: 80695
Project: 80695
Buggy source:
private void connect(PersonalKey key){
  this.disconnect();
  mModel.statusChanged(Kontalk.Status.CONNECTING);
  String network=mConfig.getString("String_Node_Str");
  String host=mConfig.getString("String_Node_Str");
  int port=mConfig.getInt("String_Node_Str");
  EndpointServer Server=new EndpointServer(network,host,port);
synchronized (this) {
    try {
      mConn=new KonConnection(Server,key.getBridgePrivateKey(),key.getBridgeCertificate());
    }
 catch (    XMPPException|PGPException ex) {
      LOGGER.log(Level.WARNING,"String_Node_Str",ex);
      mModel.statusChanged(Kontalk.Status.FAILED);
      mModel.handleException(new KonException(KonException.Error.CLIENT_CONNECTION,ex));
      return;
    }
    LOGGER.info("String_Node_Str");
    try {
      mConn.connect();
    }
 catch (    XMPPException|SmackException|IOException ex) {
      LOGGER.log(Level.WARNING,"String_Node_Str",ex);
      mModel.statusChanged(Kontalk.Status.FAILED);
      mModel.handleException(new KonException(KonException.Error.CLIENT_CONNECT,ex));
      return;
    }
    System.out.println("String_Node_Str");
    RosterListener rl=new KonRosterListener(mConn.getRoster(),this);
    mConn.getRoster().addRosterListener(rl);
    PacketFilter messageFilter=new PacketTypeFilter(Message.class);
    mConn.addPacketListener(new MessageListener(this),messageFilter);
    PacketFilter vCardFilter=new PacketTypeFilter(VCard4.class);
    mConn.addPacketListener(new VCardListener(),vCardFilter);
    PacketFilter blockingCommandFilter=new PacketTypeFilter(BlockingCommand.class);
    mConn.addPacketListener(new BlockingCommandListener(),blockingCommandFilter);
    mConn.addPacketListener(this,new AndFilter(new NotFilter(messageFilter),new NotFilter(vCardFilter),new NotFilter(blockingCommandFilter)));
    try {
      mConn.login("String_Node_Str","String_Node_Str");
    }
 catch (    XMPPException|SmackException|IOException ex) {
      LOGGER.log(Level.WARNING,"String_Node_Str",ex);
      mModel.statusChanged(Kontalk.Status.FAILED);
      mModel.handleException(new KonException(KonException.Error.CLIENT_LOGIN,ex));
      return;
    }
  }
  LOGGER.info("String_Node_Str");
  this.sendPresence();
  this.sendBlocklistRequest();
  mModel.statusChanged(Kontalk.Status.CONNECTED);
}

Fixed version (ground truth):
public void connect(PersonalKey key){
  this.disconnect();
  mModel.statusChanged(Kontalk.Status.CONNECTING);
  String network=mConfig.getString("String_Node_Str");
  String host=mConfig.getString("String_Node_Str");
  int port=mConfig.getInt("String_Node_Str");
  EndpointServer Server=new EndpointServer(network,host,port);
  try {
    mConn=new KonConnection(Server,key.getBridgePrivateKey(),key.getBridgeCertificate());
  }
 catch (  XMPPException|PGPException ex) {
    LOGGER.log(Level.WARNING,"String_Node_Str",ex);
    mModel.statusChanged(Kontalk.Status.FAILED);
    mModel.handleException(new KonException(KonException.Error.CLIENT_CONNECTION,ex));
    return;
  }
  RosterListener rl=new KonRosterListener(mConn.getRoster(),this);
  mConn.getRoster().addRosterListener(rl);
  PacketFilter messageFilter=new PacketTypeFilter(Message.class);
  mConn.addPacketListener(new MessageListener(this),messageFilter);
  PacketFilter vCardFilter=new PacketTypeFilter(VCard4.class);
  mConn.addPacketListener(new VCardListener(),vCardFilter);
  PacketFilter blockingCommandFilter=new PacketTypeFilter(BlockingCommand.class);
  mConn.addPacketListener(new BlockingCommandListener(),blockingCommandFilter);
  mConn.addPacketListener(this,new AndFilter(new NotFilter(messageFilter),new NotFilter(vCardFilter),new NotFilter(blockingCommandFilter)));
  List args=new ArrayList(0);
  Client.TASK_QUEUE.offer(new Client.Task(Client.Command.CONNECT,args));
}