PowerMock testing - set static field of class

junit static mocking powermock
Craig Anderson picture Craig Anderson · Mar 22, 2011 · Viewed 69.9k times · Source

I'm having difficulty finding a way to set a static field of a class. It's basically like this:

public class Foo{
    // ...
    private static B b = null;
}

where B is another class.

Is there any way to do this in PowerMock other than with setInternalStateFromContext()? Using the context class method seems a bit of overkill for setting one field.

Thanks.

Answer

cproinger picture cproinger · Jan 18, 2012 
Whitebox.setInternalState(Foo.class, b);

Works as long as you set a non-null value, and if theres only one field with the class of B. If you can't rely on that luxury, you have to provide the field-name and cast the null to the type you want to set. In that case you would need to write something like this:

 Whitebox.setInternalState( Foo.class, "b", (B)null );

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