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null pointer exception

 
Greenhorn
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Hi,
I am trying to understand why this piece of code does not give a null pointer exception:
String test = null;
test.valueOf(someDoubleValue);
someDoubleValue is any double number. Is this because valueOf() is a static method?
Thank you.
 
author and iconoclast
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Originally posted by Sonia Kapoor:
Is this because valueOf() is a static method?



Yes. As you know, an object isn't needed to call the static method. The compiler generates code here that never actually uses the variable "test" -- the compiled code just mentions the String class, where the method is defined.

Note that a good IDE (development environment) will warn you here, saying that you're calling a static method via a non-static context -- which is bad style, even though it's not an error.
 
Sonia Kapoor
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Thank you!
 
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