Jetty example source code file (chat.js)

This example Jetty source code file (chat.js) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Jetty tags/keywords

error, error, f, f, off, off

The Jetty chat.js source code

function $() {
  return document.getElementById(arguments[0]);
}

function $F() {
  return document.getElementById(arguments[0]).value;
}

var room = 
{
  _last: "",
  _username: null,
  
  join: function(name)
  {
    if (name == null || name.length==0 )
    {
      alert('Please enter a username!');
    }
    else
    {
       this._username=name;
       $('join').className='hidden';
       $('joined').className='';
       $('phrase').focus();
       Behaviour.apply();
       ajax.sendMessage('join', room._username);
    }
  },
  
  leave: function()
  {
       // switch the input form
       $('join').className='';
       $('joined').className='hidden';
       $('username').focus();
       Behaviour.apply();
       ajax.sendMessage('leave',room._username);
       room._username=null;
  },
  
  chat: function(text)
  {
    if (text != null && text.length>0 )
    {
        ajax.sendMessage('chat',text);
    }
  },
  
  _chat: function(message)
  {
     var divChat=document.getElementById("chat");
     var from=message.getAttribute('from');
     var special=message.getAttribute('alert');
     var text=message.childNodes[0].data;
     
     if ( special!='true' && from == room._last )
         from="...";
     else
     {
         room._last=from;
         from+=":";
     }
     
     
     
     var parentElement = divChat;
     if (special=='true')
     {
       var span = document.createElement("span");
       span.className="alert";
       divChat.appendChild(span);
       parentElement=span;
     }
     var spanFrom = document.createElement("span");
     spanFrom.className="from";
     spanFrom.innerHTML=from+" ";
     var spanText = document.createElement("span");
     spanText.className="text";
     spanText.innerHTML=text;
     var lineBreak = document.createElement("br");
     parentElement.appendChild(spanFrom);
     parentElement.appendChild(spanText);
     divChat.appendChild(lineBreak);
     divChat.scrollTop = divChat.scrollHeight - divChat.clientHeight;     
  },
   
  _members: function(message)
  {   
    try
    {
        var divMembers = document.getElementById("members");
        divMembers.innerHTML="";
        var spanMember = document.createElement("span");
        var ul = document.createElement("ul");
        spanMember.appendChild(ul);
        var x = message.getElementsByTagName("li");
        for (var i=0;i<x.length;i++)
        {
          var li = document.createElement("li");
          li.innerHTML = x[i].firstChild.nodeValue;
          ul.appendChild(li);
        } 
        divMembers.appendChild(spanMember);
    }
    catch(e)
    {
    	window.status="ERROR: members "+e.name + ": " + e.message;
        // alert("_members " + e);
    }
  }
};

ajax.addListener('chat',room._chat);
ajax.addListener('members',room._members);
ajax.addPollHandler(room._poll);

var chatBehaviours = 
{ 
  '#username' : function(element)
  {
    element.setAttribute("autocomplete","OFF"); 
    element.onkeyup = function(ev)
    {          
        var keyc=EvUtil.getKeyCode(ev);
        if (keyc==13 || keyc==10)
        {
          room.join($F('username'));
	  return false;
	}
	return true;
    } 
  },
  
  '#joinB' : function(element)
  {
    element.onclick = function(event)
    {
      room.join($F('username'));
      return false;
    }
  },
  
  '#phrase' : function(element)
  {
    element.setAttribute("autocomplete","OFF");
    element.onkeyup = function(ev)
    {   
        var keyc=EvUtil.getKeyCode(ev);
        if (keyc==13 || keyc==10)
        {
          room.chat($F('phrase'));
          $('phrase').value='';
	  return false;
	}
	return true;
    }
  },
  
  '#sendB' : function(element)
  {
    element.onclick = function(event)
    {
      room.chat($F('phrase'));
      $('phrase').value='';
      return false;
    }
  },
  
  
  '#leaveB' : function(element)
  {
    element.onclick = function()
    {
      room.leave();
      return false;
    }
  }
};

Behaviour.register(chatBehaviours);