Java中Linked中push（），pop（）方法

先看代码：

LinkedList books=new LinkedList();          books.offerFirst("java");          books.offer("C#");                   System.out.println(books);

结果自然是：[java, C#]
改变代码：

 LinkedList books=new LinkedList();          books.push("C");                  books.offer("C#");          books.offerFirst("java");          System.out.println(books);

加入了push后，代码结果变成：[java, C, C#]
改变代码：

 LinkedList books=new LinkedList();                     books.offer("C#");          books.offerFirst("java");          books.push("C");            System.out.println(books);

代码结果变成：[C, java, C#]
这时，原因观察push的方法说明：

Pushes an element onto the stack represented by this list. In other words, inserts the element at the front of this list. This method is equivalent to addFirst.Specified by: push(...) in DequeParameters:e the element to pushSince:1.6

注意上述文字中：equivalent 等同于的意思，自然就明白了上面的结果原因了。继续改进代码：

 LinkedList books=new LinkedList();                     books.offer("C#");          books.offerFirst("java");          books.push("C");          books.pop();          System.out.println(books);

查看pop的解释：

Pops an element from the stack represented by this list. In other words, removes and returns the first element of this list. This method is equivalent to removeFirst().Specified by: pop() in DequeReturns:the element at the front of this list (which is the top of the stack represented by this list)Throws:NoSuchElementException - if this list is emptySince:1.6

只要注意到This method is equivalent to removeFirst().自然就明白答案：[java, C#]的原因了。
要多看api，自然就能明白很多了。