jMock

JMock is a library that supports test-driven development1 of Java code with mock objects.

Mock objects help you design and test the interactions between the objects in your programs.

The jMock library:

  • makes it quick and easy to define mock objects, so you don't break the rhythm of programming.
  • lets you precisely specify the interactions between your objects, reducing the brittleness of your tests.
  • works well with the autocompletion and refactoring features of your IDE.
  • plugs into your favourite test framework.
  • is easy to extend.