Mocking restTemplate 返回 null

Question

出于某种原因，以下测试失败，因为“响应”是 null，但它不应该，因为我使用 when() function 返回初始化的 object。知道如何解决它吗？ 这是确切的错误：

Cannot invoke "org.springframework.http.ResponseEntity.getBody()" because "response" is null
java.lang.NullPointerException: Cannot invoke "org.springframework.http.ResponseEntity.getBody()" because "response" is null

这是测试 class：

class UtilsControllerTest {

    @Mock
    RestTemplate restTemplate=mock(RestTemplate.class);
    @Test
    void checkPermission() {
        boolean permitted = true;

        ResponseEntity<PermissionResponseModel> response = ResponseEntity.ok(new PermissionResponseModel(permitted));

        when(restTemplate.postForEntity(any(String.class), any(Map.class), any(Class.class)))
                .thenReturn(response);

        UtilsController utilsController = new UtilsController();
        assertTrue(utilsController.checkPermission("69696969", Task.MAKE_REQUEST, restTemplate));
        verify(restTemplate, times(1)).postForEntity(any(), any(), any());
    }

}

这是 UtilsController 的实现：

public class UtilsController {
    private static final String authString = "Authorization";

    /**
     * Checks if the user is authorised to do a certain task.
     *
     * @param token the identification token
     * @param task  the task
     * @return true iff user is allowed, false otherwise
     */
    public boolean checkPermission(String token, Task task, RestTemplate restTemplate) {
        HttpHeaders authHeaders = new HttpHeaders();
        authHeaders.setContentType(MediaType.APPLICATION_JSON);
        authHeaders.set(authString, token);
        String url = "http://localhost:8081/permission";

        PermissionRequestModel prm = new PermissionRequestModel();
        prm.setTask(task);
        HttpEntity<PermissionResponseModel> entity = new HttpEntity(prm, authHeaders);

        ResponseEntity<PermissionResponseModel> response =
                restTemplate.postForEntity(url, entity, PermissionResponseModel.class);
        return response.getBody().isPermitted();
    }
}

我试图模拟返回的响应实体，它也没有用。 仍然，响应是 null。但在这两种情况下，当我调试它时，响应具有正确的值，而不是 null。

Answer 1

正如 M. Deinum 所说，我正在为不同的postForEntity方法注册行为。 修复方法是：

when(restTemplate.postForEntity(anyString(), any(HttpEntity.class), any(Class.class)))
                .thenReturn(new ResponseEntity<>(new PermissionResponseModel(permitted), HttpStatus.OK));