Change key in HashMap

Hi!
Is it possible to change some key in HashMap?
I mean: I've got HashMap<String,Object> and I want to update String (key).
There is one solution possible: to make a temporary object with value, remove the whole row in HashMap and then add a new row <new_String,temporary_value>....
but is there any more elegant way to do this?
thanks

Peter__Lawrey wrote:
McNepp wrote:
Peter__Lawrey wrote:
Keys are generally considered immutable. i.e. they usually don't change. However, what you suggest is a one liner.
map.put(newKey, map.remove(oldKey));
looks alluringly elegant, but adds a mapping from "newKey" to null even if there was no such mapping before.Unless the map doesn't accept nulls in which case it throws an Exception. :-/
Object value = map.remove(oldKey);
if (value != null)
map.put(newKey, value);
And now you've broken it the other way. Maps that do accept null and have an entry for { oldKey --> null } won't get the newKey mapping.
if (map.containsKey(oldKey))
map.put(newKey, map.remove(oldKey));

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Change key in HashMap

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