public void actionPerformed(ActionEvent evt) {
    Object src = evt.getSource();

    try {
      if (src == propDialog) {
        propDialog_actionPerformed(evt);
      } else {
        pdu = new BlockPdu(context);
        if (src == setButton) {
          pdu.setPduType(BlockPdu.SET);
          pdu.addOid(toid.getText(), new AsnOctets(tvalue.getText()));
        } else if (src == getButton) {
          pdu.setPduType(BlockPdu.GET);
          pdu.addOid(toid.getText());
        } else if (src == getNextButton) {
          pdu.setPduType(BlockPdu.GETNEXT);
          pdu.addOid(toid.getText());
        }
        sendRequest(pdu);
      }
    } catch (Exception exc) {
      exc.printStackTrace();
      lmessage.setText("Exception: " + exc.getMessage());
      lmessage.setBackground(Color.red);
    }
  }
  public void actionPerformed(ActionEvent evt) {
    Object src = evt.getSource();

    try {
      if (src == propDialog) {
        propDialog_actionPerformed(evt);
      }
    } catch (Exception exc) {
      exc.printStackTrace();
    }
  }
 void propDialog_actionPerformed(ActionEvent evt) {
   String cmd = evt.getActionCommand();
   if (cmd.equals("Cancel") == false) {
     createContext(
         propDialog.getHost(),
         propDialog.getPort(),
         propDialog.getCommunityName(),
         propDialog.getSocketType());
     sendGetRequest(toid.getText());
   } else {
     // System.exit(0);
   }
 }