import org.jmock.Expectations; import org.jmock.Mockery; import org.junit.jupiter.api.Test; public class ExampleTest { @Test public void testSomething() { Mockery mockery = new Mockery(); final SomeDependency mockDependency = mockery.mock(SomeDependency.class); mockery.checking(new Expectations() {{ oneOf(mockDependency).doSomething(); will(returnValue("mocked result")); }}); SomeClass testedObject = new SomeClass(mockDependency); String result = testedObject.doSomethingWithDependency(); mockery.assertIsSatisfied(); assertEquals("mocked result", result); } }