public static void main(String[] args) {
        HashMap<String, String> map = new HashMap<>();
        map.put("format","1");
        String s = doPost("http://localhost:9066/addRule", map);
        System.out.println(s);
    }
 public static String doPost(String url, Map<String, String> param) {
        // 创建Httpclient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        try {
            RequestConfig requestConfig = RequestConfig.custom()
                    .setConnectionRequestTimeout(CONNECTION_TIMEOUT_MS)
                    .setConnectTimeout(CONNECTION_TIMEOUT_MS)
                    .setSocketTimeout(CONNECTION_TIMEOUT_MS * 10)
                    .build();

            // 创建Http Post请求
            HttpPost httpPost = new HttpPost(url);
            httpPost.setConfig(requestConfig);
            httpPost.setHeader("Content-Type", "application/json");
            // 创建参数列表
            if (param != null) {
                List<NameValuePair> paramList = new ArrayList<>();
                Iterator<Map.Entry<String, String>> it = param.entrySet().iterator();
                while (it.hasNext()) {
                    Map.Entry<String, String> entry = it.next();
                    BasicNameValuePair basicNameValuePair = new BasicNameValuePair(entry.getKey(), entry.getValue());
                    paramList.add(basicNameValuePair);
                }
                // 模拟表单
                UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList, "utf-8");
                httpPost.setEntity(entity);
            }
            // 执行http请求
            return EntityUtils.toString(httpClient.execute(httpPost).getEntity(), "utf-8");
        } catch (SocketTimeoutException e) {
            log.warn("POST request read time out:", e);
            throw SysException.of(SysException.NET_READ_TIME_OUT_EXCEPTION);
        } catch (Exception e) {
            log.error("POST request error:", e);
            throw new RuntimeException("do post request error! " + e.getMessage());
        }
    }

@Controller
public class a {

    @ResponseBody
    @PostMapping("/addRule")
    public String addRule(@RequestBody @Valid AddRuleForm form) {
        System.out.println(form.getFormat());
        return "哈哈哈";
    }
}

@Data
public class AddRuleForm implements Serializable {
    @Min(1)
    private  String format;
}

 Resolved [org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Unrecognized token 'format': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false'); nested exception is com.fasterxml.jackson.core.JsonParseException: Unrecognized token 'format': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false')<EOL> at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 1, column: 8]]