Javascript Data Structure Queue Priority Queue

var priorityQueue = new PriorityQueue();
priorityQueue.enqueue("John", 2);
priorityQueue.enqueue("Jack", 1);
priorityQueue.enqueue("Camila", 1);

console.log(priorityQueue.size());//from   ww  w. ja v a  2 s. c  om


function PriorityQueue(){

  var items = [];

  function QueueElement(element, priority){
    this.element = element;
    this.priority = priority;
  }

  this.enqueue = function(element, priority){

    //Create an object to insert.
    var queueElement = new QueueElement(element, priority);

    if(this.isEmpty()){
      items.push(queueElement);
    }else{

      var added = false;
      for(var i=0; i<items.length; i++){
        if(queueElement.priority < items[i].priority){
          items.splice(i, 0, queueElement);
          added = true;
          break;
        }
      }

      if(!added){
        items.push(queueElement);
      }

    }

  }


  this.dequeue = function(){
    return items.shift();
  }

  this.size = function(){
    return items.length;
  }

  this.isEmpty  = function(){
    return items.length == 0;
  }


}