利用Dictionary的弱引用实现的动态内存管理

DynamicMemoryManager.as

/**
 * Copyright (c) 2013 Ray Yee. All rights reserved. 
 * 
 * @author Ray Yee 
 * Created 2013-2-16 下午3:37:51
 **/
package eg
{
  import flash.utils.Dictionary;

	public class DynamicMemoryManager
	{
		private var _memory:Dictionary = new Dictionary(true);
		
		/**
		 * Constructor 
		 */		
		public function DynamicMemoryManager()
		{
			
		}
		
		public function push(value:Object):*
		{
			var data:Array;
			var key:Class = value.constructor;
			for (var item:Array in _memory)
			{
				if (_memory[item] == key)
				{
					data = item;
					break;
				}
			}
			if (data == null)
			{
				data = [];
				_memory[data] = key;
			}
			data.push(value);
			return value;
		}
		
		public function pull(key:Class):*
		{
			var data:Array = _memory[key];
			for (var item:Array in _memory)
			{
				if (_memory[item] == key)
				{
					data = item;
					break;
				}
			}
			return (data && data.length) ? data.shift() : push(new key);
		}
		
		
	}
}