4 * Copyright 2015 eddie.
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 package uk.ac.ntu.n0521366.wsyd.libs.net;
26 import java.io.ByteArrayOutputStream;
27 import java.io.IOException;
28 import java.io.InputStream;
29 import java.io.ObjectInputStream;
30 import java.io.ObjectOutputStream;
31 import java.net.Socket;
32 import java.util.List;
33 import java.util.concurrent.ConcurrentLinkedQueue;
34 import java.util.logging.Level;
35 import java.util.logging.Logger;
36 import javax.swing.SwingWorker;
42 public class NetworkStream extends SwingWorker<Boolean, NetworkMessage> {
44 private final Socket _socket;
46 static final long longSize = Long.SIZE / 8;
51 * Thread safe First In, First Out Queue of NetworkMessage objects waiting to be sent.
53 * Allows the Owner Thread to submit new messages for sending that the Worker Thread
56 protected ConcurrentLinkedQueue<NetworkMessage> _sendMessageQueue = new ConcurrentLinkedQueue<>();
58 private final NetworkMessageEventListenerManager _eventManager;
60 private ObjectOutputStream _socketOS;
62 private InputStream _socketIS;
64 private final NetworkSocketClosing _owner;
66 private ObjectInputStream _ois;
68 private ObjectOutputStream _oos;
70 private ByteArrayOutputStream _baos;
72 public NetworkStream(Socket socket, NetworkSocketClosing owner) {
73 this._socket = socket;
75 _eventManager = new NetworkMessageEventListenerManager();
79 public Boolean doInBackground() throws Exception {
81 _baos = new ByteArrayOutputStream();
82 _oos = new ObjectOutputStream(_baos);
83 _socketOS = new ObjectOutputStream(_socket.getOutputStream());
85 _socketIS = _socket.getInputStream();
86 _ois = new ObjectInputStream(_socketIS);
88 long expectedLength = longSize;
89 boolean expectingLong = true;
91 while (!this.isCancelled()) {
92 // check for incoming message
93 if (_socketIS.available() > 0) {
94 System.err.println(" reading Object from stream, bytes available: " + _socketIS.available());
98 if (_ois.available() >= expectedLength) {
99 if (expectingLong == true) {
100 expectedLength = _ois.readLong();
101 System.err.println("Expecting Object with length " + expectedLength);
102 System.err.println("Remaining bytes: " + _ois.available());
103 expectingLong = false;
106 System.err.println("About to read at least " + _ois.available() + " bytes");
108 expectedLength = longSize;
109 expectingLong = true;
113 // send a queued message
114 NetworkMessage temp = this.sendMessage();
116 if (!this.write(temp)) {
117 System.err.println("Unable to send message over TCP channel");
118 // FIXME: Potentially add logger support
127 protected void done() {
128 _owner.canCloseSocket(_key);
132 * Send a NetworkMessage over a NetworkStream.
134 * Each message is preceeded by its length as a long to avoid rare, but possible blocking
138 * @return true if message successfully sent
140 public boolean write(NetworkMessage message) {
141 boolean result = false;
142 System.err.println("NetworkStream.write()");
144 if (message != null) {
146 _oos.writeObject(message);
148 Long messageSize = new Long(_baos.size());
149 _socketOS.writeObject(message);
151 System.err.println(" bytes written: " + messageSize);
155 } catch (IOException ex) {
156 ex.printStackTrace();
157 // TODO: Implement graceful disconnect
164 * Reads NetworkMessage from the incoming stream and publishes it.
167 * @return true if message successfully published
169 public boolean read() {
170 boolean result = false;
171 System.err.println("NetworkStream.read()");
174 NetworkMessage message = null;
177 message = (NetworkMessage)_ois.readObject();
178 System.err.println(" received: " + message.toString());
179 message.setKey(_key);
183 } catch (java.io.OptionalDataException ex) {
184 System.err.println("Length: " + ex.length + " EOF: " + ex.eof);
185 ex.printStackTrace();
186 } catch (IOException ex) {
187 Logger.getLogger(NetworkStream.class.getName()).log(Level.SEVERE, null, ex);
188 // FIXME: Replace logger
189 // TODO: Graceful disconnect
190 } catch (ClassNotFoundException ex) {
191 Logger.getLogger(NetworkStream.class.getName()).log(Level.SEVERE, null, ex);
192 // FIXME: Replace logger
194 // TODO: Implement NetworkStream::read()
199 * Removes a message from the queue of pending messages.
201 * This method is called on the Worker Thread by the doInBackground() main loop.
203 * @return a message to be sent
205 protected NetworkMessage sendMessage() {
206 return this._sendMessageQueue.poll();
209 /* XXX: Methods below here all execute on the GUI Event Dispatch Thread */
212 * Adds a message to the queue of pending messages.
214 * This method will usually be called from the Owner Thread.
216 * @param message to be sent
217 * @return true if the message was added to the queue
219 public boolean queueMessage(NetworkMessage message) throws IllegalArgumentException {
220 boolean result = false;
222 if (message != null) {
224 try { // make a deep clone of the message
225 temp = NetworkMessage.clone(message);
226 result = this._sendMessageQueue.add(temp);
227 } catch (CloneNotSupportedException e) {
228 // TODO: queueMessage() log CloneNotSupportedException
235 public NetworkMessageEventListenerManager getEventManager() {
236 return this._eventManager;
240 * Fetch messages received over the stream.
242 * For delivery to event listeners; usually Swing GUI components. This method will run on the
243 * Owner Thread so must complete quickly as that is the GUI Event Dispatch Thread.
245 * @param list messages received and queued
248 protected void process(List<NetworkMessage> list) {
249 for (NetworkMessage message: list) {
250 this._eventManager.fireNetworkMessageEvent(message);