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.io.Serializable;
021import java.util.EventListener;
022
023import org.apache.commons.net.util.ListenerList;
024
025/**
026 * ProtocolCommandSupport is a convenience class for managing a list of ProtocolCommandListeners and firing ProtocolCommandEvents. You can simply delegate
027 * ProtocolCommandEvent firing and listener registering/unregistering tasks to this class.
028 *
029 *
030 * @see ProtocolCommandEvent
031 * @see ProtocolCommandListener
032 */
033
034public class ProtocolCommandSupport implements Serializable {
035    private static final long serialVersionUID = -8017692739988399978L;
036
037    private final Object source;
038    private final ListenerList listeners;
039
040    /**
041     * Creates a ProtocolCommandSupport instance using the indicated source as the source of ProtocolCommandEvents.
042     *
043     * @param source The source to use for all generated ProtocolCommandEvents.
044     */
045    public ProtocolCommandSupport(final Object source) {
046        this.listeners = new ListenerList();
047        this.source = source;
048    }
049
050    /**
051     * Adds a ProtocolCommandListener.
052     *
053     * @param listener The ProtocolCommandListener to add.
054     */
055    public void addProtocolCommandListener(final ProtocolCommandListener listener) {
056        listeners.addListener(listener);
057    }
058
059    /**
060     * Fires a ProtocolCommandEvent signalling the sending of a command to all registered listeners, invoking their
061     * {@link org.apache.commons.net.ProtocolCommandListener#protocolCommandSent protocolCommandSent() } methods.
062     *
063     * @param command The string representation of the command type sent, not including the arguments (e.g., "STAT" or "GET").
064     * @param message The entire command string verbatim as sent to the server, including all arguments.
065     */
066    public void fireCommandSent(final String command, final String message) {
067        final ProtocolCommandEvent event;
068
069        event = new ProtocolCommandEvent(source, command, message);
070
071        for (final EventListener listener : listeners) {
072            ((ProtocolCommandListener) listener).protocolCommandSent(event);
073        }
074    }
075
076    /**
077     * Fires a ProtocolCommandEvent signalling the reception of a command reply to all registered listeners, invoking their
078     * {@link org.apache.commons.net.ProtocolCommandListener#protocolReplyReceived protocolReplyReceived() } methods.
079     *
080     * @param replyCode The integer code indicating the natureof the reply. This will be the protocol integer value for protocols that use integer reply codes,
081     *                  or the reply class constant corresponding to the reply for protocols like POP3 that use strings like OK rather than integer codes (i.e.,
082     *                  POP3Repy.OK).
083     * @param message   The entire reply as received from the server.
084     */
085    public void fireReplyReceived(final int replyCode, final String message) {
086        final ProtocolCommandEvent event;
087        event = new ProtocolCommandEvent(source, replyCode, message);
088
089        for (final EventListener listener : listeners) {
090            ((ProtocolCommandListener) listener).protocolReplyReceived(event);
091        }
092    }
093
094    /**
095     * Returns the number of ProtocolCommandListeners currently registered.
096     *
097     * @return The number of ProtocolCommandListeners currently registered.
098     */
099    public int getListenerCount() {
100        return listeners.getListenerCount();
101    }
102
103    private void readObject(final java.io.ObjectInputStream in) {
104        throw new UnsupportedOperationException("Serialization is not supported");
105    }
106
107    /*
108     * Serialization is unnecessary for this class. Reject attempts to do so until such time as the Serializable attribute can be dropped.
109     */
110
111    /**
112     * Removes a ProtocolCommandListener.
113     *
114     * @param listener The ProtocolCommandListener to remove.
115     */
116    public void removeProtocolCommandListener(final ProtocolCommandListener listener) {
117        listeners.removeListener(listener);
118    }
119
120    private void writeObject(final java.io.ObjectOutputStream out) {
121        throw new UnsupportedOperationException("Serialization is not supported");
122    }
123
124}