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== and != on wrappers
Joined: Aug 25, 2008
Nov 12, 2008 12:00:00
Solving some questions about wrappers I got really in doubt on how to use == and != operators.
I've read K&B 5 chapter about wrappers but the portugueese translation drove me nuts !
What do they compare ? They look if the reference instances the same object ?? Is that ??
Joined: Sep 28, 2004
Nov 12, 2008 12:24:00
If both sides are wrappers (meaning instances), then it is comparing the references. The two sides are equal if they are the same object.
If only one side is a wrapper, then autoboxing will unbox the wrapper -- and it is the values that will be compared. The two sides are equal if they represent the same value.
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Java Gems (contributor)
I agree. Here's the link:
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