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 * https://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 */ 017package org.apache.commons.net; 018 019import java.io.ObjectInputStream; 020import java.io.ObjectOutputStream; 021import java.io.Serializable; 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 * @see ProtocolCommandEvent 030 * @see ProtocolCommandListener 031 */ 032public class ProtocolCommandSupport implements Serializable { 033 034 /** 035 * Serialization is unnecessary for this class. Reject attempts to do so until such time as the Serializable attribute can be dropped. 036 */ 037 private static final long serialVersionUID = -8017692739988399978L; 038 039 /** 040 * The source to use for all generated ProtocolCommandEvents. 041 */ 042 private final Object source; 043 044 /** 045 * The ProtocolCommandListener. 046 */ 047 private final ListenerList<ProtocolCommandListener> listeners; 048 049 /** 050 * Creates a ProtocolCommandSupport instance using the indicated source as the source of ProtocolCommandEvents. 051 * 052 * @param source The source to use for all generated ProtocolCommandEvents. 053 */ 054 public ProtocolCommandSupport(final Object source) { 055 this.listeners = new ListenerList<>(); 056 this.source = source; 057 } 058 059 /** 060 * Adds a ProtocolCommandListener. 061 * 062 * @param listener The ProtocolCommandListener to add. 063 */ 064 public void addProtocolCommandListener(final ProtocolCommandListener listener) { 065 listeners.addListener(listener); 066 } 067 068 /** 069 * Fires a ProtocolCommandEvent signaling the sending of a command to all registered listeners, invoking their 070 * {@link org.apache.commons.net.ProtocolCommandListener#protocolCommandSent protocolCommandSent()} methods. 071 * 072 * @param command The string representation of the command type sent, not including the arguments (e.g., "STAT" or "GET"). 073 * @param message The entire command string verbatim as sent to the server, including all arguments. 074 */ 075 public void fireCommandSent(final String command, final String message) { 076 if (!listeners.isEmpty()) { 077 final ProtocolCommandEvent event = new ProtocolCommandEvent(source, command, message); 078 listeners.forEach(listener -> listener.protocolCommandSent(event)); 079 } 080 } 081 082 /** 083 * Fires a ProtocolCommandEvent signaling the reception of a command reply to all registered listeners, invoking their 084 * {@link org.apache.commons.net.ProtocolCommandListener#protocolReplyReceived protocolReplyReceived()} methods. 085 * 086 * @param replyCode The integer code indicating the nature of the reply. This will be the protocol integer value for protocols that use integer reply codes, 087 * or the reply class constant corresponding to the reply for protocols like POP3 that use strings like OK rather than integer codes (i.e., 088 * POP3Repy.OK). 089 * @param message The entire reply as received from the server. 090 */ 091 public void fireReplyReceived(final int replyCode, final String message) { 092 if (!listeners.isEmpty()) { 093 final ProtocolCommandEvent event = new ProtocolCommandEvent(source, replyCode, message); 094 listeners.forEach(listener -> listener.protocolReplyReceived(event)); 095 } 096 } 097 098 /** 099 * Gets the number of ProtocolCommandListeners currently registered. 100 * 101 * @return The number of ProtocolCommandListeners currently registered. 102 */ 103 public int getListenerCount() { 104 return listeners.getListenerCount(); 105 } 106 107 /** 108 * Throws UnsupportedOperationException. 109 * 110 * @param ignored Ignored. 111 */ 112 private void readObject(final ObjectInputStream ignored) { 113 throw new UnsupportedOperationException("Serialization is not supported"); 114 } 115 116 /** 117 * Removes a ProtocolCommandListener. 118 * 119 * @param listener The ProtocolCommandListener to remove. 120 */ 121 public void removeProtocolCommandListener(final ProtocolCommandListener listener) { 122 listeners.removeListener(listener); 123 } 124 125 /** 126 * Always throws {@link UnsupportedOperationException}. 127 * 128 * @param ignored ignored. 129 * @throws UnsupportedOperationException Always thrown. 130 */ 131 private void writeObject(final ObjectOutputStream ignored) { 132 throw new UnsupportedOperationException("Serialization is not supported"); 133 } 134}