001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.net;
019
020import java.util.EventListener;
021
022/**
023 * There exists a large class of IETF protocols that work by sending an ASCII text command and arguments to a server, and then receiving an ASCII text reply.
024 * For debugging and other purposes, it is extremely useful to log or keep track of the contents of the protocol messages. The ProtocolCommandListener interface
025 * coupled with the {@link ProtocolCommandEvent} class facilitate this process.
026 * <p>
027 * To receive ProtocolCommandEvents, you merely implement the ProtocolCommandListener interface and register the class as a listener with a ProtocolCommandEvent
028 * source such as {@link org.apache.commons.net.ftp.FTPClient}.
029 *
030 *
031 * @see ProtocolCommandEvent
032 * @see ProtocolCommandSupport
033 */
034
035public interface ProtocolCommandListener extends EventListener {
036
037    /**
038     * This method is invoked by a ProtocolCommandEvent source after sending a protocol command to a server.
039     *
040     * @param event The ProtocolCommandEvent fired.
041     */
042    void protocolCommandSent(ProtocolCommandEvent event);
043
044    /**
045     * This method is invoked by a ProtocolCommandEvent source after receiving a reply from a server.
046     *
047     * @param event The ProtocolCommandEvent fired.
048     */
049    void protocolReplyReceived(ProtocolCommandEvent event);
050
051}