IndexControllerTest.java

@WebMvcTest(IndexController.class)
@AutoConfigureMockMvc
class IndexControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @Test
    @DisplayName("check if index page is rendered.")
    public void testIndexPage() throws Exception {
        mockMvc.perform(MockMvcRequestBuilders.get("/"))
                .andExpect(MockMvcResultMatchers.status().is2xxSuccessful())
                .andExpect(MockMvcResultMatchers.view().name("index"));
    }
}