View Javadoc

1   /************************************************************************
2    * Copyright (c) 1999-2006 The Apache Software Foundation.             *
3    * All rights reserved.                                                *
4    * ------------------------------------------------------------------- *
5    * Licensed under the Apache License, Version 2.0 (the "License"); you *
6    * may not use this file except in compliance with the License. You    *
7    * may obtain a copy of the License at:                                *
8    *                                                                     *
9    *     http://www.apache.org/licenses/LICENSE-2.0                      *
10   *                                                                     *
11   * Unless required by applicable law or agreed to in writing, software *
12   * distributed under the License is distributed on an "AS IS" BASIS,   *
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or     *
14   * implied.  See the License for the specific language governing       *
15   * permissions and limitations under the License.                      *
16   ***********************************************************************/
17  
18  package org.apache.james.smtpserver;
19  
20  import org.apache.james.util.mail.dsn.DSNStatus;
21  
22  /***
23    * Default command handler for handling unknown commands
24    */
25  public class UnknownCmdHandler implements CommandHandler {
26  
27      /***
28       * The name of the command handled by the command handler
29       */
30      public static final String UNKNOWN_COMMAND = "UNKNOWN";
31  
32      /***
33       * Handler method called upon receipt of an unrecognized command.
34       * Returns an error response and logs the command.
35       *
36       * @see org.apache.james.smtpserver.CommandHandler#onCommand(SMTPSession)
37      **/
38      public void onCommand(SMTPSession session) {
39  
40          //If there was message failure, don't consider it as an unknown command
41          if (session.getState().get(SMTPSession.MESG_FAILED) != null) {
42              return;
43          }
44  
45          session.getResponseBuffer().append("500 "+DSNStatus.getStatus(DSNStatus.PERMANENT, DSNStatus.DELIVERY_INVALID_CMD))
46                        .append(" Command ")
47                        .append(session.getCommandName())
48                        .append(" unrecognized.");
49          String responseString = session.clearResponseBuffer();
50  
51          session.writeResponse(responseString);
52      }
53  
54  }