public WxSimpleResult addKfAccountTest() {         // my_access_value 是我的 access_token 的值         String url = "https://api.weixin.qq.com/customservice/kfaccount/add?access_token=my_access_value";                  HttpHeaders httpHeaders = new HttpHeaders();         // Json 穿擦         httpHeaders.setContentType(MediaType.APPLICATION_JSON);                  // 第一中请求方式         HashMap<String, String> parameters = new HashMap<>();         // 我添加的客服微信的账号         parameters.put("kf_wx", "my_wx_account_value");         HttpEntity<HashMap<String, String>> entity = new HttpEntity<>(parameters, httpHeaders);         //  class WxSimpleResult 对象字段结构如：{"errcode":0,"errmsg":"ok"}         ResponseEntity<WxSimpleResult> response = restTemplate.postForEntity(url, entity, WxSimpleResult.class);         // 第二种请求方式         MultiValueMap<Object, Object> body2 = new LinkedMultiValueMap<>();         body2.add("kf_wx", "my_wx_account_value");         HttpEntity<MultiValueMap<Object, Object>> entity2 = new HttpEntity<>(body2, httpHeaders);         ResponseEntity<WxSimpleResult> response2 = restTemplate.postForEntity(url, entity2, WxSimpleResult.class);         // 第三中请求方式，使用对象包装参数（ AddKfRequest 类中字段 kf_wx,business_id）         AddKfRequest body3 = AddKfRequest.create("my_wx_account_value", null);         HttpEntity<AddKfRequest> entity3 = new HttpEntity<>(body3, httpHeaders);         ResponseEntity<WxSimpleResult> response3 = restTemplate.postForEntity(url, entity3, WxSimpleResult.class);         return null; } *** 以上三种参数封装方式传参 都响应 412 Precondition Failed: [no body] *** // ####################### 参数和返回值实体类 ############################# // 返回值接收对象 @Getter @Setter public class WxSimpleResult implements Serializable {     @Serial     private static final long serialVersionUID = 1L;     /**      * 错误响应码,成功时返回 0      *      */     private Integer errcode;     /**      * 错误响应消息,成功时返回 ok      */     private String errmsg; } // 请求参数对象 @Getter @Setter public class AddKfRequest implements Serializable {     @Serial     private static final long serialVersionUID = 1L;     private String kf_wx;     private Integer business_id;     public static AddKfRequest create(String kfWx, String businessId) {         AddKfRequest addKfRequest = new AddKfRequest();         addKfRequest.setKf_wx(kfWx);         if (null != businessId && !businessId.isBlank()) {             addKfRequest.setBusiness_id(Integer.valueOf(businessId));         }         return addKfRequest;     } } 代码截图如下： [图片] ********** 如上三种 参数封装的方式请求，均为异常响应 412 Precondition Failed: [no body] *********