Re: Map.get(key) returns null after inserting key

In a previous article, "Mize-ze" <zahy.bnaya@xxxxxxxxx> said:
Hello,
I am inserting a key and a object into a Map. later in the code I try
to retrieve the object by calling
Map.get(key) and I get a null.
I can't see where is my problem...

I only had to read this far to guess what the problem is - you haven't
implemented hashCode on your key class, or if you have, you haven't
implemented it properly, and you're using HashMap.

I know this, because I made the same mistake (AGAIN) a few weeks ago. I
changed something from TreeSet to HashSet and things weren't working the
way I expected.

--
Paul Tomblin <ptomblin@xxxxxxxxx> http://blog.xcski.com/
It might not be practical, it might not be a good idea, but it could work.
Sort of like Windows.
-- berry
.

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