Configure tomcat to accept post request

Question

How can I configure tomcat so when a post request is made the request parameters are outputted to a jsp file? Do I need a servlet which forwards to a jsp or can this be handled within a jsp file ?

Here is my method which sends the post request to the tomcat server -

 public void sendContentUsingPost() throws IOException {

        HttpConnection httpConn = null;
          String url = "http://LOCALHOST:8080/services/getdata";
     //   InputStream is = null;
        OutputStream os = null;

        try {
          // Open an HTTP Connection object
          httpConn = (HttpConnection)Connector.open(url);
          // Setup HTTP Request to POST
          httpConn.setRequestMethod(HttpConnection.POST);

          httpConn.setRequestProperty("User-Agent",
            "Profile/MIDP-1.0 Confirguration/CLDC-1.0");
          httpConn.setRequestProperty("Accept_Language","en-US");
          //Content-Type is must to pass parameters in POST Request
          httpConn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");


          // This function retrieves the information of this connection
          getConnectionInformation(httpConn);

                  String params;
          params = "?id=test&data=testdata";
                      System.out.println("Writing "+params);
          //            httpConn.setRequestProperty( "Content-Length", String.valueOf(params.length()));

          os = httpConn.openOutputStream();

          os.write(params.getBytes());

 } finally {
          if(os != null)
            os.close();
      if(httpConn != null)
            httpConn.close();
    }

        }

Thanks

Answer 1

First of all, your query string is invalid.

params = "?id=test&data=testdata";

It should have been

params = "id=test&data=testdata";

The ? is only valid when you concatenate it to the request URL as a GET query string. You should not use it when you want to write it as POST request body.

Said that, if this service is not supposed to return HTML (e.g. plaintext, JSON, XML, CSV, etc), then use a servlet. Here's an example which emits plaintext.

String id = request.getParameter("id");
String data = request.getParameter("data");
response.setContentType("text/plain");
response.setContentEncoding("UTF-8");
response.getWriter().write(id + "," + data);

If this service is supposed to return HTML, then use JSP. Change the URL to point to the JSP's one.

String url = "http://LOCALHOST:8080/services/getdata.jsp";

And then add the following to the JSP template to print the request parameters.

${param.id}
${param.data}

Either way, you should be able to get the result (the response body) by reading the URLConnection#getInputStream().

See also:

• How to use URLConnection to fire and handle HTTP requests?

---

Unrelated to the concrete problem, you are not taking character encoding carefully into account. I strongly recommend to do so. See also the above link for detailed examples.

Answer 2

A servlet can handle both get and post request in following manner:

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
   //remaning usedefinecode
    } 

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

If you have a tomcat installation from scratch, don't forget to add the following lines to web.xml in order to let the server accept GET, POST, etc. request:

 <servlet>
    <servlet-name>default</servlet-name>
    <servlet-class>org.apache.catalina.servlets.DefaultServlet</servlet-class>

    ...

    <init-param>
            <param-name>readonly</param-name>
            <param-value>false</param-value>
    </init-param>

   ...

</servlet>