test_stub.java

// This is the stub generated by our fictional framework
Database stubDatabase = stub(Database.class);

// Class that we want to test and that uses stubDatabase
ApplicationService service = new ApplicationService(stubDatabase);

// Here we are telling the stub what to return
when(stubDatabase.getApplicationKey(APP_ID))
    .thenReturn(new ApplicationKey(APP_ID, Status.REVOKED));

// Test ApplicationService behaviour
assertThat(service.isRevoked(APP_ID), is(true));