pom.xml

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
		</dependency>

UserControllerTest

@RunWith(SpringRunner.class)
@SpringBootTest
public class UserControllerTest {

	@Autowired
	private WebApplicationContext wac;

	private MockMvc mockMvc;

	@Before
	public void setup() {
		mockMvc = MockMvcBuilders.webAppContextSetup(wac).build();
	}

	@Test
	public void whenQuerySuccess() throws Exception {
		String result = mockMvc.perform(
				get("/user").param("username", "jojo").param("age", "18").param("ageTo", "60").param("xxx", "yyy")
						// .param("size", "15")    //MockMvcRequestBuilders
						// .param("page", "3")
						// .param("sort", "age,desc")
						.contentType(MediaType.APPLICATION_JSON_UTF8))
				.andExpect(status().isOk()).andExpect(jsonPath("$.length()").value(3)) //MockMvcResultMatchers
				.andReturn().getResponse().getContentAsString();
		
		System.out.println(result);
	}