AS3: Data-tube ... an evolved concept

A data-tube concept based class.

package engine 
{
 /**
  * @file CDataTube.as
  * @author Abhishek Kumar
  */
 public class CDataTube
 {
  
  public function CDataTube() 
  {
   
  }
  
  public function manageItem(iCommand:Boolean, iItem:*, iList:*):Array
  {
   if (iList == undefined)
   {
    iList = [];
    iList = addItem(iItem, iList);
   }
   else
    iList = (iCommand)? addItem(iItem, iList) : deleteItem(isPresent(iItem, iList), iList);
   return iList;
  }
  
  private function addItem(iItem:*, iList:Array):Array
  {
   iList.push(iItem);
   return iList;
  }
  
  private function deleteItem(iIndex:int, iList:Array):Array
  {
   for (var j:int = iIndex; j < iList.length; j++)
    iList[j] = iList[j + 1];
   iList.length--;
   return iList;
  }
  
  private function isPresent(iItem:*, iList:Array):int
  {
   for (var i:int = 0; i < iList.length; i++ )
    if (iList[i] == iItem)
     return i;
   return -1;
  }
  
 }

}