前言

在Spring单元测试中，如果不想生成的对象受Spring管理的话，就可以使用Mock注解，为了减少单测与spring框架的耦合，并且尽量不使用真实对象进行模拟，可以使用@InjectMocks和@Mock注解

Mockito使用

生成@Mock、@Spy备注的mock对象，用

@BeforeEach
	void setUp() {
		MockitoAnnotations.openMocks(this);
	}

定义一个实体类

@Data
public class UserQuery {

    
    private Long id;


    private String account;


    private String username;

    private Long deptId;


    private List<Long> roleIds;
    
    private String password;
    

}

定义一个service接口

public Boolean save(UserQuery userQuery) {
		UserDTO userDTO = new UserDTO();
		userDTO.setUsername(userQuery.getAccount());
		R<Boolean> result = remoteUserAdminService.isExist(userDTO);
		if (!Objects.equals(result.getCode(), CommonConstants.SUCCESS)) {
			throw new BussException("判断用户名是否存在错误");
		}
		if (result.getData()) {
			throw new BussException("用户名已存在");
		}
		userDTO.setNickName(userQuery.getUsername());
		result = remoteUserAdminService.user(userDTO);
		if (!Objects.equals(result.getCode(), CommonConstants.SUCCESS)) {
			throw new BussException("保存用户异常");
		}
		return result.getData();
	}

测试单元如下

@DisplayName("用户模块测试")
public class UserServiceImplTest {

	@InjectMocks
	private UserServiceImpl userService;

	@Mock
	private RemoteUserService remoteUserService;


	@Mock
	private RemoteUserAdminService remoteUserAdminService;

	@BeforeEach
	void setUp() {
		MockitoAnnotations.openMocks(this);
	}

	@Nested
	@DisplayName("新建用户单元测试")
	public class UserAddTest {

		@Test
		@DisplayName("保存用户，查询用户名是否存在，三方系统返回调用失败 => 返回异常")
		void save_1_test() {
			UserQuery userQuery = new UserQuery();
			userQuery.setUsername("aa");
			UserDTO userDTO = new UserDTO();
			userDTO.setUsername(userQuery.getAccount());
			R<Boolean> result = R.restResult(null, 1, "操作失败");
			Mockito.when(remoteUserAdminService.isExist(Mockito.any(UserDTO.class))).thenReturn(result);
			Assertions.assertThrows(BussException.class, () -> {
				userService.save(userQuery);
			});
			Mockito.verify(remoteUserAdminService, times(1)).isExist(Mockito.any(UserDTO.class));
		}

		@Test
		@DisplayName("保存用户，查询用户名是否存在，三方系统返回用户名已经存在 => 返回异常")
		void save_2_test() {
			UserQuery userQuery = new UserQuery();
			userQuery.setUsername("aa");			
			UserDTO userDTO = new UserDTO();
			userDTO.setUsername(userQuery.getAccount());
			R<Boolean> result = R.restResult(true, 0, "操作成功");
			Mockito.when(remoteUserService.isExist(Mockito.any(UserDTO.class))).thenReturn(result);
			Assertions.assertThrows(BussException.class, () -> {
				userService.save(userQuery);
			});
			Mockito.verify(remoteUserService, times(1)).isExist(Mockito.any(UserDTO.class));
		}

		@Test
		@DisplayName("保存用户，三方系统返回保存异常 => 返回异常")
		void save_3_test() {
			UserQuery userQuery = new UserQuery();
			userQuery.setUsername("aa");
			UserDTO userDTO = new UserDTO();
			userDTO.setUsername(userQuery.getAccount());
			R<Boolean> result = R.restResult(false, 0, "操作成功");
			Mockito.when(remoteUserService.isExist(Mockito.any(UserDTO.class))).thenReturn(result);
			R<Boolean> saveR = R.restResult(false, 1, "操作失败");
			Mockito.when(remoteUserService.user(Mockito.any(UserDTO.class))).thenReturn(saveR);
			Assertions.assertThrows(BussException.class, () -> {
				userService.save(userQuery);
			});
			Mockito.verify(remoteUserService, times(1)).isExist(Mockito.any(UserDTO.class));
			Mockito.verify(remoteUserService, times(1)).user(Mockito.any(UserDTO.class));
		}

		@Test
		@DisplayName("保存用户，三方系统返回成功 => 保存用户成功")
		void save_4_test() {
			UserQuery userQuery = new UserQuery();
			userQuery.setUsername("aa");
			UserDTO userDTO = new UserDTO();
			userDTO.setUsername(userQuery.getAccount());
			R<Boolean> result = R.restResult(false, 0, "操作成功");
			Mockito.when(remoteUserService.isExist(Mockito.any(UserDTO.class))).thenReturn(result);
			R<Boolean> saveR = R.ok(true, "操作成功");
			Mockito.when(remoteUserService.user(Mockito.any(UserDTO.class))).thenReturn(saveR);
			Boolean isSuccess = userService.save(userQuery);
			Mockito.verify(remoteUserService, times(1)).isExist(Mockito.any(UserDTO.class));
			Mockito.verify(remoteUserService, times(1)).user(Mockito.any(UserDTO.class));
			Assertions.assertTrue(isSuccess);
		}

	}

}

其中

Mockito.when

Mockito.when是模拟一个方法返回值，如

Mockito.when(remoteUserService.isExist(Mockito.any(UserDTO.class))).thenReturn(result);
			R<Boolean> saveR = R.ok(true, "操作成功");

模拟方法中调用isExist，返回result结果，Mockito.any(UserDTO.class)是传入一个UserDTO值

Mockito.verify

Mockito.verify(remoteUserService, times(1))，是验证方法中remoteUserService是不是被被用了一次

总结

在单元测试中，Mockito可以模拟出对象不受Spring框架影响，这样在没有Bean的注入和管理下，启动和验证就比较快，当然，写单元测试的时候，具体问题具体分析