code: protected URI doPostCreate(String path, Object o, MultivaluedMap<String, String> headers) throws ClientException {
          this.readLock.lock();
          try {
              WebResource.Builder requestBuilder = getResourceWrapper().rewritten(path, HttpMethod.POST).getRequestBuilder();
              requestBuilder = ensurePostCreateJsonHeaders(headers, requestBuilder, true, false);
              ClientResponse response = requestBuilder.post(ClientResponse.class, o);
              errorIfStatusNotEqualTo(response, ClientResponse.Status.OK, ClientResponse.Status.CREATED);
              try {
                  return response.getLocation();
              } finally {
                  response.close();
              }
          } catch (ClientHandlerException ex) {
              throw new ClientException(ClientResponse.Status.INTERNAL_SERVER_ERROR, ex.getMessage());
          } finally {
              this.readLock.unlock();
          }
      }
docs: Creates a resource specified as a JSON object.
  
  @param path the the API to call.
  @param o the object that will be converted to JSON for sending. Must
  either be a Java bean or be recognized by the object mapper.
  @param headers If no Content Type header is provided, this method adds a
  Content Type header for JSON.
  @return the URI representing the created resource, for use in subsequent
  operations on the resource.
  @throws ClientException if a status code other than 200 (OK) and 201
  (Created) is returned.