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Date: Mon, 25 Feb 2013 19:54:22 +0000
From: lipska the kat <"nospam at neversurrender dot co dot uk">
Organization: Trollbusters 3
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Subject: Re: BlueJ don't know what i did wrong
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On 25/02/13 18:52, John B. Matthews wrote:
> In article<PqydnQ_Wh-MT9bbMnZ2dnUVZ8tGdnZ2d@bt.com>,
>   lipska the kat<"nospam at neversurrender dot co dot uk">  wrote:
>
>> On 25/02/13 12:50, John B. Matthews wrote:
>>> In article<veSdnb08Iq8m27bMnZ2dnUVZ8g2dnZ2d@bt.com>,
>>>    lipska the kat<"nospam at neversurrender dot co dot uk">   wrote:
>>>
>>>> <http://docs.oracle.com/javase/6/docs/api/java/util/Stack.html>
>>>>
>>>> <pseudo-code>
>>>>
>>>> Stack s = new Stack()
>>>> ...
>>>> </pseudo-code>
>>>
>>> Please don't recommend raw types for new code, and don't recommend
>>> an API that says explicitly, "A more complete and consistent set of
>>> LIFO stack operations is provided by the Deque interface and its
>>> implementations, which should be used in preference to this class."

Why? why use a Deque instead of a Stack? ... because the documentation 
says so? ... A Stack is an abstraction, it's a very widely understood 
abstraction, everyone who has ever read a book on software knows what a 
stack is. push, pop, peek, they are Stack methods, you don't need 
anything else for a Stack, even peek is questionable. Providing a method 
to add something to the bottom of a Stack doesn't make sense in terms of 
the 'stackness' of a Stack. It just adds meaningless and unneeded 
complexity and confusion, particularly for a beginner to Java.

If you are reading someone else's code and you see

Stack s = new Stack();

you know EXACTLY what to expect. What are you to expect when you see a 
Deque ... could be anything.

Can you give me one good reason to use a Deque instead of a Stack when a 
stack is what I want apart from "because the documentation says so"

lipska

-- 
Lipska the Kat©: Troll hunter, sandbox destroyer
and farscape dreamer of Aeryn Sun