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Double.NaN

 
rani bedi
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Can you explain me the output..??
 
Hanna Habashy
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hi:
NaN is a constant holding a Not-a-Number value.
NaN doesn't equal anything, not even itself.
so
Double.NaN == Double.Nan// is false
Your created two objects references of type Double. The bit holders for both references refere to Double.NaN.
Then
a.equal(b) will return true
 
William Brogden
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It is instructive to look at the source for java.lang.Double - look at the method for equals and for isNaN.
Everybody studying for the exam should have the source (unzip src.zip) and study it when these questions come up.
Bill
 
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