Why do Double.parseDouble(null) and Integer.parseInt(null) throw different exceptions?

java exception nullpointerexception numberformatexception
pho79 picture pho79 · May 1, 2013 · Viewed 40.7k times · Source

Why do Double.parseDouble(null) and Integer.parseInt(null) throw different exceptions?

Is this a historical accident or intentional? The documentation clearly states two types of exceptions for Double.parseDouble(...) and one for Integer.parseInt(), but it seems inconsistent:

Integer.parseInt(null); // throws java.lang.NumberFormatException: null

However 

Double.parseDouble(null); // throws java.lang.NullPointerException

Answer

Floris Velleman picture Floris Velleman · May 1, 2013

It is reasonable to expect the same exceptions to be thrown for null; however, these api's are very old and may not be able to be changed at this point.

And:

Since the exception behavior is long-standing and specified in the JavaDoc, it is impractical to change either method's behavior at this time. Closing as will not fix.

As taken from: Bug Report: Integer.parseInt() and Double.parseDouble() throw different exceptions on null.

Like others have stated: It's likely made by different authors.

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