NullPointerException from Boolean

Question

This is one for the java purists I think. I recently had an issue with a method to perform a custom parsing of String values to a Boolean. A simple enough task, but for some

Answer 1

My suggestion? Don't return Boolean, return boolean and throw an exception:

static boolean parseBoolean(String s)
{
  if ("1".equals(s)) return true;
  if ("0".equals(s)) return false;

  throw new IllegalArgumentException(s + " is not a boolean value.");
}

Adopting an approach like the above will help avoid you accidentally referencing a null Boolean object.

See the excellent answer from NilsH to see why your original method is throwing an exception.