我正在尝试从我的 android 向我在 GAE 上的服务器发出 http post 请求。

在 android 端，帖子似乎运行良好，但在服务器端，doPost(...) 永远不会被调用。谁能告诉我为什么？

这是我的相关安卓代码:

protected Integer doInBackground(View... arg0)
{
    try
    {
        HttpClient httpClient = new DefaultHttpClient();
//      HttpPost httpPost = new HttpPost("http://elf-security.appspot.com");
        HttpPost httpPost = new HttpPost("http://elf-security.appspot.com/gae_hellowordl");
//      HttpPost httpPost = new HttpPost("http://localhost:8888/gae_hellowordl");
        httpPost.addHeader("test", "Success!");

        Log.i(TAG, "Just about to send http request to " + httpPost.getURI());
        HttpResponse httpResponse = httpClient.execute(httpPost);
        Log.i(TAG, "Received http response..");

        Log.i(TAG, httpResponse.toString());
    } catch (ClientProtocolException e) 
    {
        e.printStackTrace();
    } catch (IOException e) 
    {
        e.printStackTrace();
    }

    return null;
}

这是我的相关服务器代码:

public class GAE_HelloWordlServlet extends HttpServlet
{
    private Logger LOG;

    public GAE_HelloWordlServlet()
    {
        LOG = Logger.getLogger("GAE_HelloWordlServlet");
        LOG.info("GAE_HelloWordlServlet()");
    }

    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException
    {
        LOG.info("doGet():  request test header:  " + req.getHeader("test"));
    }

    public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException
    {
        LOG.info("doPost():  request test header:  " + req.getHeader("test"));
    }
}

提前致谢!

编辑

这是我的 web.xml 文件:

<?xml version="1.0" encoding="utf-8" standalone="no"?><web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.5" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
    <servlet>
        <servlet-name>GAE_HelloWordl</servlet-name>
        <servlet-class>gae.helloworld.GAE_HelloWordlServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>GAE_HelloWordl</servlet-name>
        <url-pattern>/*</url-pattern>
<!--        <url-pattern>/gae_hellowordl</url-pattern> -->
    </servlet-mapping>
    <welcome-file-list>
        <welcome-file>index.html</welcome-file>
    </welcome-file-list>
    <servlet>
        <servlet-name>SystemServiceServlet</servlet-name>
        <servlet-class>com.google.api.server.spi.SystemServiceServlet</servlet-class>
        <init-param>
            <param-name>services</param-name>
            <param-value/>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>SystemServiceServlet</servlet-name>
        <url-pattern>/_ah/spi/*</url-pattern>
    </servlet-mapping>
</web-app>

最佳答案

仔细检查您的 web.xml 并确保 URL 路径正确映射到处理它的 servlet:

<web-app xmlns="http://java.sun.com/xml/ns/javaee" version="2.5">
    <servlet>
        <servlet-name>helloworld</servlet-name>
        <servlet-class>com.mysite.GAE_HelloWordlServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>helloworld</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>
</web-app>

查看开发指南 here了解更多详情:

Servlets and URL Paths

web.xml defines mappings between URL paths and the servlets that handle requests with those paths. The web server uses this configuration to identify the servlet to handle a given request and call the class method that corresponds to the request method (e.g. the doGet() method for HTTP GET requests).

... ...

更新:

• 案例 1:Android 模拟器 -> Appengine dev_server(都在同一台机器上运行):

  查看此问答:Android Application doPost

• 案例 2:Android 真实设备 -> Appengine dev_server(都在同一网络上):

  首先确保 Appengine dev_appserver 可以在网络上访问(通过使用参数 --address=0.0.0.0 启动 dev_appserver，更多详细信息请参见 here)。其次在你的 android 应用程序中，更改你的代码以指向正确的 IP 地址，假设你的桌面 IP 是 192.168.1.6，使用 HttpPost httpPost = new HttpPost("http://192.168.1.6:8888/gae_hellowordl");

关于android - 如何将 http post 从 android 发送到 google app engine 服务器？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14992991/