Mocking package private classes

Question

Using Mockito or another similar framework. Is there a way to mock a package-private class? I am trying to test my service layer mocking my DAO classes. The problem is that the DAO instances are package private and only can be obtained through a factory.

MyPackagePrivateDao mockedDao = mock(MyPackagePrivateDao.class);

The compiler says that the class cannot be accessed from outside the package. Do you have any example?

Thanks

Answer 1

This is not possible with Mockito, it requires to modify the bytecode of the actual class. This is not a planned feature.

Don't you have interfaces that you could eventually mock for these DAOs ?

Another option is to look on PowerMock which is great to deal with legacy code, ie when the software design is forcing you to mock statics, private, final, etc.

Answer 2

Presumably, your problem is that your SUT (and therefore its test) is in a different package from the class that you want to mock, otherwise there wouldn't be a problem.

The way I would solve this is to write a static utility method in the test class for the class that you want to mock. This utility method should just create and return a mock of the desired class, which it can do because it's in the right package. You can then call the utility method instead of calling mock(MyPackagePrivateDao.class).