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About Hash Map

Raj chiru
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Joined: Aug 12, 2008
Posts: 142
Is it preferable to store large amount of data in Hash map?and what's disadvantage of hash map?
Maneesh Godbole
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Joined: Jul 26, 2007
Posts: 10828

"Large amounts" is a relative term. How do you define it?

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Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46412
Have a look at this Java™ Tutorials section.
Brian Legg
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Joined: Nov 07, 2008
Posts: 488
A HashMap is only as good as it's hashing algorithm. For instance a HashMap that throws everything into 1 bucket is equally as useless as a HashMap which throws everything into it's own bucket. The short answer to your question would be "yes", a HashMap or any of the HashXXX objects are designed to divide and conquer large sets of data. If you need other features such as index then a different collection would be needed.

Hope that helps somewhat... if not, please give more details.

~Currently preparing for SCJP6
I agree. Here's the link:
subject: About Hash Map
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