基本的にメッセージを受け取り、それをエコーバックするコードを次に示します。問題は、まったく応答しないことです:( Google App Engine、私のアプリケーションページで、「要求された URL /guestbook がこのサーバーに見つかりませんでした」というエラーが表示されます。
package guestbook;
import java.io.IOException;
import java.util.logging.Logger;
import javax.servlet.http.*;
import com.google.appengine.api.xmpp.JID;
import com.google.appengine.api.xmpp.Message;
import com.google.appengine.api.xmpp.MessageBuilder;
import com.google.appengine.api.xmpp.XMPPService;
import com.google.appengine.api.xmpp.XMPPServiceFactory;
@SuppressWarnings("serial")
public class GuestbookServlet extends HttpServlet {
private static final Logger LOG = 
          Logger.getLogger(GuestbookServlet.class.getName());
public void doPost(HttpServletRequest req, HttpServletResponse resp)
        throws IOException {
       // Parse incoming message
    XMPPService xmpp = XMPPServiceFactory.getXMPPService();
    Message msg = xmpp.parseMessage(req);
    JID jid = msg.getFromJid();
    String body = msg.getBody();
    LOG.info(jid.getId() + " --> JEliza: " + body);
    // Get a response from Eliza
    String response = "echo: " + body;
    LOG.info(jid.getId() + " <-- JEliza: " + response);
    // Send out response
    msg = new MessageBuilder()
        .withRecipientJids(jid)
        .withBody(response)
        .build();
    xmpp.sendMessage(msg);
    /*Message message = xmpp.parseMessage(req);
    JID fromJid = message.getFromJid();
    String body = message.getBody();
    String respMsg = null;
    if (body.equals("/list")) {
        respMsg = "Hi";
      } else if (body.equals("/help")) {
        respMsg = "Welcome to the Guestbook Chatbot!\nThe following commands are supported: \n /list \n /help";
      } else {
        respMsg = "Command '" + body + "' not supported! \nEnter '/help' for list of commands.";
      }
    JID tojid = new JID(fromJid.getId());
    Message msg = new MessageBuilder().withRecipientJids(tojid).withBody(respMsg).build();
    boolean messageSent = false;
    xmpp = XMPPServiceFactory.getXMPPService();
    if (xmpp.getPresence(tojid).isAvailable()) {
      SendResponse status = xmpp.sendMessage(msg);
      messageSent = (status.getStatusMap().get(tojid) == SendResponse.Status.SUCCESS);
    }*/
  }
}