您可以用来
ResponseEntity显式设置标题。棘手的一点是弄清楚您的内容实际上有多长时间：
@RequestMapping(value = "/contacts", method = RequestMethod.POST)public ResponseEntity<Map<String, ContactInfo>> addContactInfo(@RequestBody Map<String, ContactInfo> contactInfoDto) throws JsonProcessingException { ContactInfo contactInfo = contactInfoDto.get("contact"); if (contactInfo == null) { throw new IllegalArgumentException("Contact not found."); } contactInfo = this.contactInfoManager.addNew(contactInfo); Map<String, ContactInfo> map = new HashMap<>(); map.put("contact", contactInfo); HttpHeaders headers = new HttpHeaders(); headers.set(HttpHeaders.CONTENT_LENGTH, String.valueOf(new ObjectMapper().writevalueAsString(map).length())); return new ResponseEntity<Map<String, ContactInfo>>(map, headers, HttpStatus.CREATED);}测试：
$ curl -v http://localhost:8080/contacts/ -X POST -d '{ "contact": { "name": "foo" } }' -H 'Content-Type: application/json' && echo* Trying ::1...* Connected to localhost (::1) port 8080 (#0)> POST /contacts/ HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.43.0> Accept: */*> Content-Type: application/json> Content-Length: 32> * upload completely sent off: 32 out of 32 bytes< HTTP/1.1 201 Created< Server: Apache-Coyote/1.1< X-Application-Context: application< Content-Type: application/json;charset=UTF-8< Content-Length: 26< Date: Fri, 10 Jun 2016 13:24:23 GMT< * Connection #0 to host localhost left intact{"contact":{"name":"foo"}}
