用于POST请求的HttpURLConnection App Engine Java示例不起作用

我正在尝试在app引擎应用程序下使用urlfetch执行POST请求。

我已按照“使用HttpURLConnection”部分下的App Engine文档（此处为https://developers.google.com/appengine/docs/java/urlfetch/usingjavanet ）中的简单示例提取的说明（和代码）进行了操作。 。

import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.net.URLEncoder; import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.IOException; import java.io.OutputStreamWriter; String message = URLEncoder.encode("my message", "UTF-8"); try { URL url = new URL("http://httpbin.org/post"); HttpURLConnection connection = (HttpURLConnection) url.openConnection(); connection.setDoOutput(true); connection.setRequestMethod("POST"); OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream()); writer.write("message=" + message); writer.close(); if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) { // OK } else { // Server returned HTTP error code. } } catch (MalformedURLException e) { // ... } catch (IOException e) { // ... } 

为了测试这个POST请求，我使用以下网站“ http://httpbin.org/post ”。

获取和连接有效 – 但是，连接是作为GET而不是POST发送的。

以下是我对此请求的回复：

   
Method Not Allowed
The method GET is not allowed for the requested URL. 

有人遇到过这个问题吗？

任何帮助表示赞赏。

Answer 1

由于这个问题在3年后仍然获得了相当多的观点，我将在此确认文档示例中给出的方法适用于对给定URL发出POST请求，并且自该问题首次发布以来保持不变。 工作代码示例如下：

 String message = URLEncoder.encode("my message", "UTF-8"); URL url = new URL("http://httpbin.org/post"); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setDoOutput(true); conn.setRequestMethod("POST"); OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream()); writer.write("message=" + message); writer.close(); StringBuffer responseString = new StringBuffer(); String line; BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); while ((line = reader.readLine()) != null) { responseString.append(line); } reader.close(); 

收到以下答复：

 Code: 200, message: { "args": {}, "data": "", "files": {}, "form": { "message": "my message" }, "headers": { "Accept-Encoding": "gzip,deflate,br", "Content-Length": "18", "Content-Type": "application/x-www-form-urlencoded", "Host": "httpbin.org", "User-Agent": "AppEngine-Google; (+http://code.google.com/appengine; appid: s~ )", "X-Cloud-Trace-Context": "," }, "json": null, "origin": "107.178.194.113", "url": "http://httpbin.org/post"} 

Answer 2

您是否尝试过调用OutputStreamWriter的flush（）方法？

Answer 3

也许您必须设置内容类型请求属性：

 connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");