我有一个控制器，应允许下载具有任意内容类型的文件：

@GetMapping(value="/download/{directory}/{name}",
            consumes=MediaType.ALL_VALUE)
@Timed
public ResponseEntity<byte[]> downloadFile(@PathVariable String directory,
                                           @PathVariable String name) {
    log.debug("REST request to download File : {}/{}", directory, name);

    byte[] content = "it works".getBytes();
    HttpHeaders headers = new HttpHeaders();
    headers.add(HttpHeaders.CONTENT_TYPE, "text/plain");
    return new ResponseEntity<>(content, headers, HttpStatus.OK);
}

我想在这样的单元测试中进行测试：

...
private MockMvc restFileMockMvc;

@Before
public void setup() {
    MockitoAnnotations.initMocks(this);

    final FileResource fileResource = new FileResource(fileService);
    this.restFileMockMvc = MockMvcBuilders.standaloneSetup(fileResource)
        .setCustomArgumentResolvers(pageableArgumentResolver)
        .setControllerAdvice(exceptionTranslator)
        .setConversionService(createFormattingConversionService())
        .setMessageConverters(jacksonMessageConverter)
        .setValidator(validator).build();
}

@Test
@Transactional
public void downloadFile() throws Exception {
    String url = "/api/download/it/works.txt";
    restFileMockMvc.perform(get(url).header(HttpHeaders.ACCEPT, "*/*"))
                   .andDo(MockMvcResultHandlers.print()) // Debugging only!
                   .andExpect(status().isOk());
}

但显然，内容类型存在问题，分别。接受标头。 MockMvcResultHandlers.print()产生以下内容：

MockHttpServletRequest:
      HTTP Method = GET
      Request URI = /api/download/DIRDIR/NAMENAME
       Parameters = {}
          Headers = {Accept=[*/*]}
             Body = <no character encoding set>
    Session Attrs = {}

Handler:
             Type = com.example.storage.web.rest.FileResource
           Method = public org.springframework.http.ResponseEntity<byte[]> com.example.storage.web.rest.FileResource.downloadFile(java.lang.String,java.lang.String)

Async:
    Async started = false
     Async result = null

Resolved Exception:
             Type = org.springframework.web.HttpMediaTypeNotAcceptableException

ModelAndView:
        View name = null
             View = null
            Model = null

FlashMap:
       Attributes = null

MockHttpServletResponse:
           Status = 406
    Error message = null
          Headers = {Content-Type=[application/problem+json]}
     Content type = application/problem+json
             Body = {"type":"https://www.jhipster.tech/problem/problem-with-message","title":"Not Acceptable","status":406,"detail":"Could not find acceptable representation","path":"/api/download/DIRDIR/NAMENAME","message":"error.http.406"}
    Forwarded URL = null
   Redirected URL = null
          Cookies = []

看起来请求是通过发送的Accept: */*。那么，Spring抱怨什么呢？