HashMap memory usage


my program will do this:

- create HashMap a
- add mappings
- prune many mappings (maybe 80% or so)
- HashMap a will be stored as a property in Object b (b.hashMap)
- there will be many b objects.

I'm thinking that HashMap a might have much wasted space because of the objects that existed initially but are no longer there.

So I'm thinking about doing something like this (after pruning a):

- HashMap compactA = new HashMap(a)
- b.hashMap = compactA (instead of b.hashMap = a)

What do you think? Will this be more memory efficient? Or should I not bother?
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b.hashMap = a;
is better if all a is needed as it is, this will involve less memory operations

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I doubt you'll get much saving doing that (if any).
ycompAuthor Commented:
ok cool guys thanks.
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