Mocking a concrete class using EasyMock

See the EasyMock Class Extension documentation and download it from the SourceForge project. You can't mock final methods though.

EDIT: This is now part of EasyMock for v3 and above, as noted in comments.

Powermock extends EasyMock and allows you to mock concrete types, even final and static methods.

PowerMock is a framework that extend other mock libraries such as EasyMock with more powerful capabilities. PowerMock uses a custom classloader and bytecode manipulation to enable mocking of static methods, constructors, final classes and methods, private methods, removal of static initializers and more.

Yes: http://easymock.org/EasyMock2_4_ClassExtension_Documentation.html