Spring Boot 2.x基础教程：构建RESTful API与单元测试

@Data
public class User {

    private Long id;
    private String name;
    private Integer age;

}

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>

@RestController
@RequestMapping(value = "/users")     // 通过这里配置使下面的映射都在/users下
public class UserController {

    // 创建线程安全的Map，模拟users信息的存储
    static Map users = Collections.synchronizedMap(new HashMap());

    /**
     * 处理"/users/"的GET请求，用来获取用户列表
     *
     * @return
     */
    @GetMapping("/")
    public List getUserList() {
        // 还可以通过@RequestParam从页面中传递参数来进行查询条件或者翻页信息的传递
        List r = new ArrayList(users.values());
        return r;
    }

    /**
     * 处理"/users/"的POST请求，用来创建User
     *
     * @param user
     * @return
     */
    @PostMapping("/")
    public String postUser(@RequestBody User user) {
        // @RequestBody注解用来绑定通过http请求中application/json类型上传的数据
        users.put(user.getId(), user);
        return "success";
    }

    /**
     * 处理"/users/{id}"的GET请求，用来获取url中id值的User信息
     *
     * @param id
     * @return
     */
    @GetMapping("/{id}")
    public User getUser(@PathVariable Long id) {
        // url中的id可通过@PathVariable绑定到函数的参数中
        return users.get(id);
    }

    /**
     * 处理"/users/{id}"的PUT请求，用来更新User信息
     *
     * @param id
     * @param user
     * @return
     */
    @PutMapping("/{id}")
    public String putUser(@PathVariable Long id, @RequestBody User user) {
        User u = users.get(id);
        u.setName(user.getName());
        u.setAge(user.getAge());
        users.put(id, u);
        return "success";
    }

    /**
     * 处理"/users/{id}"的DELETE请求，用来删除User
     *
     * @param id
     * @return
     */
    @DeleteMapping("/{id}")
    public String deleteUser(@PathVariable Long id) {
        users.remove(id);
        return "success";
    }

}

@RunWith(SpringRunner.class)
@SpringBootTest
public class Chapter21ApplicationTests {

    private MockMvc mvc;

    @Before
    public void setUp() {
        mvc = MockMvcBuilders.standaloneSetup(new UserController()).build();
    }

    @Test
    public void testUserController() throws Exception {
        // 测试UserController
        RequestBuilder request;

        // 1、get查一下user列表，应该为空
        request = get("/users/");
        mvc.perform(request)
                .andExpect(status().isOk())
                .andExpect(content().string(equalTo("[]")));

        // 2、post提交一个user
        request = post("/users/")
                .contentType(MediaType.APPLICATION_JSON)
                .content("{\"id\":1,\"name\":\"测试大师\",\"age\":20}");
        mvc.perform(request)
                .andExpect(content().string(equalTo("success")));

        // 3、get获取user列表，应该有刚才插入的数据
        request = get("/users/");
        mvc.perform(request)
                .andExpect(status().isOk())
                .andExpect(content().string(equalTo("[{\"id\":1,\"name\":\"测试大师\",\"age\":20}]")));

        // 4、put修改id为1的user
        request = put("/users/1")
                .contentType(MediaType.APPLICATION_JSON)
                .content("{\"name\":\"测试终极大师\",\"age\":30}");
        mvc.perform(request)
                .andExpect(content().string(equalTo("success")));

        // 5、get一个id为1的user
        request = get("/users/1");
        mvc.perform(request)
                .andExpect(content().string(equalTo("{\"id\":1,\"name\":\"测试终极大师\",\"age\":30}")));

        // 6、del删除id为1的user
        request = delete("/users/1");
        mvc.perform(request)
                .andExpect(content().string(equalTo("success")));

        // 7、get查一下user列表，应该为空
        request = get("/users/");
        mvc.perform(request)
                .andExpect(status().isOk())
                .andExpect(content().string(equalTo("[]")));

    }

}

import static org.hamcrest.Matchers.equalTo;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;