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null pointer exception

Sonia Kapoor
Greenhorn

Joined: Nov 01, 2005
Posts: 3
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.
Ernest Friedman-Hill
author and iconoclast
Marshal

Joined: Jul 08, 2003
Posts: 24183
    
  34

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.


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Sonia Kapoor
Greenhorn

Joined: Nov 01, 2005
Posts: 3
Thank you!
 
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