public void receiveMsg(Message msg) {
   // System.out.println(msg.getSubject() + " : " + msg.getBody());
   String subject = msg.getSubject();
   if (subject != null) {
     if (subject.equals("online")) {
       onlineUsers.addElement(new HostItem(msg.getBody()));
       displayMessage(msg.getBody() + " : Online", onlineClientAttrSet);
     } else if (subject.equals("offline")) {
       onlineUsers.removeElement(new HostItem(msg.getBody()));
       displayMessage(msg.getBody() + " : Offline", offlineClientAttrSet);
     } else if (subject.equals("eavesdrop enabled")) {
       Object[] values = jListOnlineUsers.getSelectedValues();
       if (values == null) return;
       for (int i = 0; i < values.length; i++) {
         ((HostItem) values[i]).eavesDroppingEnabled = true;
       }
       jListOnlineUsers.updateUI();
     } else if (subject.equals("eavesdrop disabled")) {
       Object[] values = jListOnlineUsers.getSelectedValues();
       if (values == null) return;
       for (int i = 0; i < values.length; i++) {
         ((HostItem) values[i]).eavesDroppingEnabled = false;
       }
       jListOnlineUsers.updateUI();
     } else if (subject.equals("globaleavesdrop enabled")) {
       displayMessage("Global Eavesdropping Enabled", onlineClientAttrSet);
     } else if (subject.equals("globaleavesdrop disabled")) {
       displayMessage("Global Eavesdropping Disabled", offlineClientAttrSet);
     } else {
       String to = msg.getTo();
       String from = msg.getFrom() == null ? "server" : msg.getFrom();
       String body = msg.getBody() != null ? msg.getBody() : "";
       if (jTextFieldUser.getText().equals(to)) { // this message is sent to us
         displayMessage(subject, from, body, incomingMsgAttrSet);
       } else { // this is an eavesdrop message
         displayMessage(subject, to, from, body, eavesdropAttrSet);
       }
     }
   } else {
     subject = "";
     String to = msg.getTo();
     String from = msg.getFrom() == null ? "server" : msg.getFrom();
     String body = msg.getBody() != null ? msg.getBody() : "";
     if (jTextFieldUser.getText().equals(to)) { // this message is sent to us
       displayMessage(subject, from, body, incomingMsgAttrSet);
     } else { // this is an eavesdrop message
       displayMessage(subject, to, from, body, eavesdropAttrSet);
     }
   }
 }