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.io.OutputStream;
32 import java.net.Socket;
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 ObjectOutputStream _socketOS;
60 private InputStream _socketIS;
62 private final NetworkSocketClosing _owner;
64 private ObjectInputStream _ois;
66 private ObjectOutputStream _oos;
68 private ByteArrayOutputStream _baos;
70 NetworkStream(Socket socket, NetworkSocketClosing owner) {
71 this._socket = socket;
76 public Boolean doInBackground() throws Exception {
78 _baos = new ByteArrayOutputStream();
79 _oos = new ObjectOutputStream(_baos);
80 _socketOS = new ObjectOutputStream(_socket.getOutputStream());
82 _socketIS = _socket.getInputStream();
83 _ois = new ObjectInputStream(_socketIS);
85 long expectedLength = longSize;
86 boolean expectingLong = true;
88 while (!this.isCancelled()) {
90 // check for incoming message
91 if (_socketIS.available() >= expectedLength) {
92 if (expectingLong == true) {
93 expectedLength = _ois.readLong();
94 expectingLong = false;
98 expectedLength = longSize;
102 // send a queued message
103 NetworkMessage temp = this.dequeueMessage();
105 if (!this.write(temp)) {
106 System.err.println("Unable to send message over TCP channel");
107 // FIXME: Potentially add logger support
116 protected void done() {
117 _owner.canCloseSocket(_key);
121 * Send a NetworkMessage over a NetworkStream.
123 * Each message is preceeded by its length as a long to avoid rare, but possible blocking
127 * @return true if message successfully sent
129 public boolean write(NetworkMessage message) {
130 boolean result = false;
132 if (message != null) {
134 _oos.writeObject(message);
136 long messageSize = _baos.size();
137 _socketOS.writeLong(messageSize);
138 _baos.writeTo(_socketOS);
142 } catch (IOException ex) {
143 // TODO: Implement graceful disconnect
150 * Reads NetworkMessage from the incoming stream and publishes it.
153 * @return true if message successfully published
155 public boolean read() {
156 boolean result = false;
159 NetworkMessage message = (NetworkMessage)_ois.readObject();
163 } catch (IOException ex) {
164 Logger.getLogger(NetworkStream.class.getName()).log(Level.SEVERE, null, ex);
165 // FIXME: Replace logger
166 // TODO: Graceful disconnect
167 } catch (ClassNotFoundException ex) {
168 Logger.getLogger(NetworkStream.class.getName()).log(Level.SEVERE, null, ex);
169 // FIXME: Replace logger
171 // TODO: Implement NetworkStream::read()
176 * Removes a message from the queue of pending messages.
178 * This method is called on the Worker Thread by the doInBackground() main loop.
180 * @return a message to be sent
182 protected NetworkMessage dequeueMessage() {
183 return this._sendMessageQueue.poll();
186 /* XXX: Methods below here all execute on the GUI Event Dispatch Thread */
189 * Adds a message to the queue of pending messages.
191 * This method will usually be called from the Owner Thread.
193 * @param message to be sent
194 * @return true if the message was added to the queue
196 public boolean queueMessage(NetworkMessage message) throws IllegalArgumentException {
197 boolean result = false;
199 if (message != null) {
201 try { // make a deep clone of the message
202 temp = NetworkMessage.clone(message);
203 result = this._sendMessageQueue.add(temp);
204 } catch (CloneNotSupportedException e) {
205 // TODO: queueMessage() log CloneNotSupportedException