This week's book giveaway is in the OO, Patterns, UML and Refactoring forum.
We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line!
See this thread for details.
The moose likes Beginning Java and the fly likes  null pointer exception Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login

JavaRanch » Java Forums » Java » Beginning Java
Bookmark " null pointer exception " Watch " null pointer exception " New topic

null pointer exception

Sonia Kapoor

Joined: Nov 01, 2005
Posts: 3
I am trying to understand why this piece of code does not give a null pointer exception:
String test = null;
someDoubleValue is any double number. Is this because valueOf() is a static method?
Thank you.
Ernest Friedman-Hill
author and iconoclast

Joined: Jul 08, 2003
Posts: 24189

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.

[Jess in Action][AskingGoodQuestions]
Sonia Kapoor

Joined: Nov 01, 2005
Posts: 3
Thank you!
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link:
subject: null pointer exception
It's not a secret anymore!