@Override
	public boolean offer(E e) {
		if(size() >= capacity) {
			E head = peek();
			if (this.comparator().compare(e, head) <= 0){
				return true;
			}
			//当队列满时，就要淘汰顶端队列
			poll();
		}
		return super.offer(e);
	}
@ Override public boolean offer ( E e ) { if ( size ( ) >= capacity ) { E head = peek ( ) ; if ( this . comparator ( ) . compare ( e , head ) <= 0 ) { return true ; } poll ( ) ; } return super . offer ( e ) ; }
加入元素，当队列满时，淘汰末尾元素
@param e 元素
@return 加入成功与否