Re: idea for more efficient HashMap

From:
Lars Enderin <lars.enderin@telia.com>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 17 Jan 2013 10:23:19 +0100
Message-ID:
<50F7C307.7060407@telia.com>
2013-01-16 23:31, Robert Klemme skrev:

On Tuesday, January 15, 2013 6:56:29 AM UTC+1, Kevin McMurtrie wrote:

In article <9hc2f8ltgn1bmdsrk8vb9kuu1vi5dkl2r5@4ax.com>,
 Roedy Green <see_website@mindprod.com.invalid> wrote:

Inside HashMap are little glue Entry objects that point to the key and
value.

What if you could implement an interface on your objects so that
HashMap could use them directly without separate key or Entry glue?.

e.g. getKey()
       getPrev()
       getNext()
       setPrev()
       setNext()

One drawback would be your objects could live on only one such
space-efficient HashMap.


I've done this when efficiency demanded it. The downside is that you
can't implement java.util.Map or java.util.Dictionary because of the way
put(K,V) is declared.


Why that? I actually have done that implementation (see above) and it is consistent with the Map interface.

I will not see posts from Google because I must filter them as spam


That might be a mistake - you'll might lose valuable feedback that way.


He will not see your post then...

--
Lars Enderin

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