Java applet to servlet: is it really possible?

I am wishing to connect to a servlet from within an applet and have scoured the net looking for examples.  I have located a few and have copied their code but it just doesn't work for me.  I am able to send data to the servlet but whenever I try to read from it I get this exception:

java.security.AccessControlException: access denied (java.util.PropertyPermission http.strictPostRedirect read)

Now, once again I have searched the net for this problem and it seems to have cropped up dozens of times.  Unfortunately I have gone though each one and I cannot find that any of them have been solved.  That leads me to wonder if I am trying to do something which simply isn't possible but then again why would other people be posting code that's supposed to work?

I have attached the code for the applet and the servlet both of which I downloaded from another site anyway.  Can anyone see why the applet fails?  I am really hoping it's a configuration issue on the server side.  BTW, signing the applet has been suggested as a possible solution to this problem on some sites but this is not appropriate in this context as it will be impossible to deliver this particular applet signed.

The environment is:

* Java 6 Update 3
* Firefox 2.0.0.11 browser
* Winstone 0.9.9 servlet container
* Both server and applet running on Windows Vista

Thanks very much,

KP

import java.applet.*;
import java.awt.*;
import java.io.*;
import java.net.*;
 
/**
 * Applet-Servlet communication example.<P>
 *
 * The Applet.  This applet allows you to type in a message, send it to a
 * servlet, and view what the servlet sends back.
 *
 * @author	James Farmer
 * @version	03-Aug-2000
 **/
 
public class EgApplet extends Applet {
  TextField servletUrlField;
  TextField messageField;
  TextArea responseField;
  Button transmitButton;
 
/**
 * This method just adds the components to the applet
 **/
 
  public void init() {
    super.init();
    this.setLayout(new BorderLayout());
 
    Panel topPanel = new Panel();
    topPanel.setLayout(new GridLayout(0,1));
 
    Panel servletUrlPanel = new Panel();
    servletUrlPanel.setLayout(new BorderLayout());
    servletUrlPanel.add("West", new Label("Servlet URL:", Label.RIGHT));
    servletUrlPanel.add("Center", servletUrlField = new TextField("http://mindy.cs.bham.ac.uk/servlets/appletServletExample.EgServlet"));
    topPanel.add(servletUrlPanel);
 
    Panel messageFieldPanel = new Panel();
    messageFieldPanel.setLayout(new BorderLayout());
    messageFieldPanel.add("West", new Label("Message to send:", Label.RIGHT));
    messageFieldPanel.add("Center", messageField = new TextField());
    topPanel.add(messageFieldPanel);
 
    this.add("North", topPanel);
    this.add("Center", responseField = new TextArea());
    responseField.setEditable(false);
    this.add("South", transmitButton = new Button("Transmit"));
  }
 
 
 
/**
 * Method to intercept clicks on the "transmit" button.  Note that we're using
 * the Java 1.0.2 event model here to ensure maximum compatibility with old
 * browsers.
 **/
 
  public boolean action(Event evt, Object obj) {
    if (obj.equals("Transmit")) {
      this.interactWithServlet();
      return true;
    }
    return false;
  }
 
 
/**
 * This method causes the applet to interact with the servlet.  Basically, the
 * method writes the message to the servlet, then reads the response and sticks
 * it in the "response" field.
 **/
 
  private void interactWithServlet() {
    try {
 
// Create an object we can use to communicate with the servlet
      URL servletURL = new URL(servletUrlField.getText());
      URLConnection servletConnection = servletURL.openConnection();
      servletConnection.setDoOutput(true);  // to allow us to write to the URL
      servletConnection.setUseCaches(false);  // to ensure that we do contact
                                              // the servlet and don't get
                                              // anything from the browser's
                                              // cache
 
// Write the message to the servlet
      PrintStream out = new PrintStream(servletConnection.getOutputStream());
      out.println(messageField.getText());
      out.close();
 
// Now read in the response
      InputStream in = servletConnection.getInputStream();
      StringBuffer response = new StringBuffer();
      int chr;
      while ((chr=in.read())!=-1) {
        response.append((char) chr);
      }
      in.close();
      responseField.setText(response.toString());
 
 
    } catch (IOException e) {
      e.printStackTrace();
      responseField.setText("An error occurred: " + e.toString());
    }
  }
 
}
 
 
 
import java.io.*;
import java.util.*;
 
import javax.servlet.*;
import javax.servlet.http.*;
 
/**
 * Applet-Servlet communication example.<P>
 *
 * The Servlet.  Basically, this reads in whatever's sent to it then sends
 * back an appropriate message.
 *
 * @author	James Farmer
 * @version	03-Aug-2000
 **/
 
public class EgServlet extends HttpServlet {
 
 
/**
 * Method to handle GET queries.
 **/
 
  public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    resp.setContentType("text/plain");
    PrintWriter out = resp.getWriter();
    out.println("Error: this servlet does not support the GET method!");
    out.close();
  }
 
 
/** 
 * Method to handle POST queries.  It reads in from the input stream, then
 * writes out what it read along with a datestamp and some description.
 **/
 
  public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
 
// Read in the message from the servlet
    StringBuffer msgBuf = new StringBuffer();
    BufferedReader fromApplet = req.getReader();
    String line;
    while ((line=fromApplet.readLine())!=null) {
      if (msgBuf.length()>0) msgBuf.append('\n');
      msgBuf.append(line);
    }
    fromApplet.close();
 
// Write the message back to the applet
    resp.setContentType("text/plain");
    PrintWriter toApplet = resp.getWriter();
    toApplet.println("I (the servlet) received a message \"" + msgBuf.toString() + "\"");
    toApplet.println("at " + (new Date()).toString());
    toApplet.println("and sent this text in response.   Hope you enjoy it!");
    toApplet.close();
  }
 
}

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