工具類方法

實現原理

List list = new ArrayList();//非同步的。

list = MyCollections.synList(list);//返回一個同步的list.







//給非同步的集合加鎖。

class MyCollections{

	public static  List synList(List list){
		
		return new MyList(list);
	}

	private class MyList implements List{
	private List list;
	
	private static final Object lock = new Object();
	MyList(List list){	
		this.list = list;	
	}
	
	public boolean add(Object obj){
		synchronized(lock)
		{
			return list.add(obj);
		}
	}
	
	public boolean remove(Object obj){
		synchronized(lock)
		{
			return list.remove(obj);
		}
	}

}
}