Unit tests for web layers involve testing the controllers—REST and otherwise—so we recommend the following:

• Using Mock MVC for web layers built on Spring MVC.
• Jersey Test Framework is a good choice for REST services built using Jersey and JAX-RS.

A quick example of setting up the Mock MVC framework is shown in the following example:

    @RunWith(SpringRunner.class)
    @WebMvcTest(TodoController.class)
    public class TodoControllerTest {

      @Autowired
      private MockMvc mvc;

      @MockBean
      private TodoService service;

      //Tests

    }

Using @WebMvcTest will allow us to use autowire MockMvc and execute web requests. A great feature of @WebMVCTest is that it only instantiates the controller components. All other Spring components are expected to be mocked and can be autowired using @MockBean.