1 /*** 2 * 3 * Copyright 2004 Hiram Chirino 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You 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 implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.activeio; 18 19 import java.io.IOException; 20 21 22 /*** 23 * A AsynchChannelFilter can be used as a filter between a {@see org.activeio.AsynchChannel} 24 * and it's {@see org.activeio.ChannelConsumer}. Most {@see org.activeio.AsynchChannel} 25 * that are not directly accessing the network will extends the AsynchChannelFilter since they act as a 26 * filter between the client and the network. O 27 * 28 * @version $Revision$ 29 */ 30 public class FilterAsynchChannel implements AsynchChannel, AsynchChannelListener { 31 32 final protected AsynchChannel next; 33 protected AsynchChannelListener channelListener; 34 35 public FilterAsynchChannel(AsynchChannel next) { 36 this.next = next; 37 } 38 39 /*** 40 */ 41 public void setAsynchChannelListener(AsynchChannelListener channelListener) { 42 this.channelListener = channelListener; 43 if (channelListener == null) 44 next.setAsynchChannelListener(null); 45 else 46 next.setAsynchChannelListener(this); 47 } 48 49 /*** 50 * @see org.activeio.Channel#write(org.activeio.channel.Packet) 51 */ 52 public void write(Packet packet) throws IOException { 53 next.write(packet); 54 } 55 56 /*** 57 * @see org.activeio.Channel#flush() 58 */ 59 public void flush() throws IOException { 60 next.flush(); 61 } 62 63 /*** 64 * @see org.activeio.Disposable#dispose() 65 */ 66 public void dispose() { 67 next.dispose(); 68 } 69 70 /*** 71 * @see org.activeio.Service#start() 72 * @throws IOException if the next channel has not been set. 73 */ 74 public void start() throws IOException { 75 if( next == null ) 76 throw new IOException("The next channel has not been set."); 77 if( channelListener ==null ) 78 throw new IOException("The UpPacketListener has not been set."); 79 next.start(); 80 } 81 82 /*** 83 * @see org.activeio.Service#stop(long) 84 */ 85 public void stop(long timeout) throws IOException { 86 next.stop(timeout); 87 } 88 89 /*** 90 * @see org.activeio.AsynchChannelListener#onPacket(org.activeio.channel.Packet) 91 */ 92 public void onPacket(Packet packet) { 93 channelListener.onPacket(packet); 94 } 95 96 /*** 97 * @see org.activeio.AsynchChannelListener#onPacketError(org.activeio.channel.ChannelException) 98 */ 99 public void onPacketError(IOException error) { 100 channelListener.onPacketError(error); 101 } 102 103 /*** 104 * @return Returns the next. 105 */ 106 public AsynchChannel getNext() { 107 return next; 108 } 109 110 /*** 111 * @return Returns the packetListener. 112 */ 113 public AsynchChannelListener getAsynchChannelListener() { 114 return channelListener; 115 } 116 117 public Object narrow(Class target) { 118 if( target.isAssignableFrom(getClass()) ) { 119 return this; 120 } 121 return next.narrow(target); 122 } 123 124 public String toString() { 125 return next.toString(); 126 } 127 }