import org.jmock.Expectations; import org.jmock.integration.junit4.JUnitRuleMockery; import org.junit.Rule; import org.junit.Test; public class ExampleTest { @Rule public JUnitRuleMockery context = new JUnitRuleMockery(); @Test public void testExampleMethod() { final SomeDependency mockDependency = context.mock(SomeDependency.class); context.checking(new Expectations() {{ oneOf(mockDependency).someMethod(); will(returnValue("mocked value")); }}); Example example = new Example(mockDependency); String result = example.exampleMethod(); assertEquals("mocked value", result); } }