javascript中利用數組實現的迴圈隊列代碼

//迴圈隊列
function CircleQueue(size){
this.initQueue(size);
}
CircleQueue.prototype = {
//初始化隊列
initQueue : function(size){
this.size = size;
this.list = new Array();
this.capacity = size + 1;
this.head = 0;
this.tail = 0;
},
//壓入隊列
enterQueue : function(ele){
if(typeof ele == "undefined" || ele == ""){
return;
}
var pos = (this.tail + 1) % this.capacity;
if(pos == this.head){//判斷隊列是否已滿
return;
}else{
this.list[this.tail] = ele;
this.tail = pos;
}
},
//從隊列中取出頭部資料
delQueue : function(){
if(this.tail == this.head){ //判斷隊列是否為空白
return;
}else{
var ele = this.list[this.head];
this.head = (this.head + 1) % this.capacity;
return ele;
}
},
//查詢隊列中是否存在此元素，存在返回下標，不存在返回-1
find : function(ele){
var pos = this.head;
while(pos != this.tail){
if(this.list[pos] == ele){
return pos;
}else{
pos = (pos + 1) % this.capacity;
}
}
return -1;
},
//返回隊列中的元素個數
queueSize : function(){
return (this.tail - this.head + this.capacity) % this.capacity;
},
//清空隊列
clearQueue : function(){
this.head = 0;
this.tail = 0;
},
//判斷隊列是否為空白
isEmpty : function(){
if(this.head == this.tail){
return true;
}else{
return false;
}
}
}