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Switching order for equals operator  RSS feed

 
Brian Schotky
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Hi all,

I've seen in several places that a way to avoid null pointer exceptions is to switch the order of the equals operator. For example, using



Instead of:



Although this seems like a good idea, doesn't this make it harder to debug down the line if you run into problems? Isn't is basically hiding the fact that you have a NPE where you shouldn't?

Just curious what your thoughts were.

Thanks!
 
Rob Spoor
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In my opinion, you should only write this code if otherwise you would have written In other words, if you already intended to have the null check in place.
 
Campbell Ritchie
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If there is any chance of "dog" being null, then dog.equals("Fido") will throw an Exception and "Fido".equals(dog) will not throw an Exception.
 
Patricia Samuel
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General Practice is this only that Rob has suggested.

 
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