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Java Unit Testing in Java What to Test Know Your Bounds

Mary McCallum
Mary McCallum
4,659 Points

What is a Null Pointer Exception?

This course runs through the examples of using exceptions in unit testing. But so far it has not explained clearly what exactly Exceptions are or what a Null Pointer Exception is? Can somebody explain? I'm going through the motions of doing the exercises but it hasn't clearly explained the theory behind it.

2 Answers

This is an Exception that is thrown when you are trying to do something with a null value. This could be trying to take the length of a null object or trying to access the field of a null object.

These links from Oracle and GeeksforGeeks do a good job to explain it in more detail.

I hope this helps!