今天遇到一个比较基础，又没遇到过的问题。

这是使用httpClient调用接口的时候报的错误，错误就是http的请求头不正确。但是调用接口的是共用方法，以前都是正常用的，怎么这次就不行了呢？换了一个请求方法就好了。

话不多说，直接看解决方案。两个post请求的方法，总有一个是适合你的。根据自己项目的选择的httpClient版本进行选择不同的方法。

方法一：

public static String doPostJson(String url, String json,String token_header) throws Exception {// 创建Httpclient对象CloseableHttpClient httpClient = HttpClients.createDefault();CloseableHttpResponse response = null;String resultString = "";try {// 创建Http Post请求HttpPost httpPost = new HttpPost(url);// 创建请求内容httpPost.setHeader("HTTP Method","POST");httpPost.setHeader("Connection","Keep-Alive");httpPost.setHeader("Content-Type","application/json;charset=utf-8");httpPost.setHeader("x-authentication-token",token_header);StringEntity entity = new StringEntity(json);entity.setContentType("application/json;charset=utf-8");httpPost.setEntity(entity);// 执行http请求response = httpClient.execute(httpPost);if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {resultString = EntityUtils.toString(response.getEntity(), "UTF-8");}} catch (Exception e) {throw e;} finally {try {if(response!=null){response.close();}} catch (IOException e) {e.printStackTrace();}}return resultString;
}

方法二：

public static String doPostForBooking(String urles, String json) throws Exception {HttpURLConnection connection = null;BufferedReader br = null;InputStream inputStream = null;// 存放数据StringBuffer sbf = new StringBuffer();try {// 创建远程url连接对象URL url = new URL(urles);// 通过远程url连接对象打开一个连接，强转成httpURLConnection类connection = (HttpURLConnection) url.openConnection();connection.setRequestMethod("POST");// 允许写出connection.setDoOutput(true);// 允许读入connection.setDoInput(true);// 不使用缓存connection.setUseCaches(false);// 设置参数类型是json格式connection.setRequestProperty("Content-Type", "application/json;charset=utf-8");connection.connect();String body = json;BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(connection.getOutputStream(), "utf-8"));writer.write(body);writer.close();// 通过connection连接，获取输入流int responseCode = connection.getResponseCode();if (responseCode == HttpURLConnection.HTTP_OK) {inputStream = connection.getInputStream();// 将输入流转换为字符串// 封装输入流is，并指定字符集br = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));String temp = null;while ((temp = br.readLine()) != null) {sbf.append(temp);sbf.append("\r\n");}}} catch (Exception e) {e.printStackTrace();} finally {if (null != br) {try {br.close();} catch (Exception e2) {e2.printStackTrace();}}if (null != inputStream) {try {inputStream.close();} catch (Exception e2) {e2.printStackTrace();}}// 关闭远程连接connection.disconnect();}return sbf.toString().replaceAll("(\r\n|\n)", "");
}