public void send(Message message) {
try {
// force keyframe? ditch all the other messages on the queue
// since this message will overwrite everything
if (message.isBlockMessage() && ((BlockMessage) message).getForceKeyFrame()) {
blockDataQ.clear();
notifyQueueListener(0);
}
// stick message on queue
blockDataQ.put(message);
// if the queue is backed up, purge it of duplicate blocks
int qSizeInBlocks = getQueueSizeInBlocks();
if (qSizeInBlocks > ScreenShareInfo.MAX_QUEUE_SIZE_FOR_PAUSE) {
if (ScreenShareInfo.getPurgeBackedUpQueue()) {
purgeBlockDataQ();
}
notifyQueueListener(qSizeInBlocks);
}
// if we're being slow, notify also
if (ScreenShareInfo.adjustPauseFromQueueSize && perfStats.isSlow()) {
notifyPerformanceListener(true);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
@ThreadSafe
public class NetworkStreamSender implements NextBlockRetriever, NetworkStreamListener {
public static final String NAME = "NETWORKSTREAMSENDER: ";
private ExecutorService executor;
private LinkedBlockingQueue<Message> blockDataQ;
private final int numThreads;
private final String host;
private final int port;
private final String room;
private final boolean httpTunnel;
private NetworkSocketStreamSender[] socketSenders;
private NetworkHttpStreamSender[] httpSenders;
private boolean tunneling = false;
private boolean stopped = true;
private int numRunningThreads = 0;
private Dimension screenDim;
private Dimension blockDim;
private BlockManager blockManager;
private NetworkConnectionListener listener;
private QueueListener queueListener;
private PerformanceListener performanceListener;
private final SequenceNumberGenerator seqNumGenerator = new SequenceNumberGenerator();
private PerformanceStats perfStats = PerformanceStats.getInstance();
public NetworkStreamSender(
BlockManager blockManager,
String host,
int port,
String room,
Dimension screenDim,
Dimension blockDim,
boolean httpTunnel) {
blockDataQ = new LinkedBlockingQueue<Message>(ScreenShareInfo.MAX_QUEUED_MESSAGES);
this.blockManager = blockManager;
this.host = host;
this.port = port;
this.room = room;
this.screenDim = screenDim;
this.blockDim = blockDim;
this.httpTunnel = httpTunnel;
numThreads = ScreenShareInfo.NETWORK_SENDER_COUNT;
System.out.println(NAME + "Starting up " + numThreads + " sender threads.");
executor = Executors.newFixedThreadPool(numThreads);
}
public void addNetworkConnectionListener(NetworkConnectionListener listener) {
this.listener = listener;
}
public void addQueueListener(QueueListener queueListener) {
this.queueListener = queueListener;
}
public void addPerformanceListener(PerformanceListener performanceListener) {
this.performanceListener = performanceListener;
}
private void notifyNetworkConnectionListener(ExitCode reason) {
if (listener != null) {
listener.networkConnectionException(reason);
}
}
private void notifyQueueListener(int queueSize) {
if (queueListener != null) {
if (queueSize == 0) {
queueListener.onQueueCleared();
} else {
queueListener.onQueueBackedup(queueSize);
}
}
}
private void notifyPerformanceListener(boolean slow) {
if (performanceListener != null) {
performanceListener.onSlowPerformance(slow);
}
}
public boolean connect() {
int failedAttempts = 0;
socketSenders = new NetworkSocketStreamSender[numThreads];
try {
NetworkSocket socket = new NetworkSocket(host, port);
for (int i = 0; i < numThreads; i++) {
try {
createSender(i, socket);
numRunningThreads++;
} catch (ConnectionException e) {
failedAttempts++;
}
}
} catch (ConnectionException e) {
e.printStackTrace();
failedAttempts = numThreads;
}
if ((failedAttempts == numThreads) && httpTunnel) {
System.out.println(NAME + "Trying http tunneling");
failedAttempts = 0;
numRunningThreads = 0;
if (tryHttpTunneling()) {
tunneling = true;
System.out.println(NAME + "Will use http tunneling");
httpSenders = new NetworkHttpStreamSender[numThreads];
for (int i = 0; i < numThreads; i++) {
try {
createHttpSender(i);
numRunningThreads++;
} catch (ConnectionException e) {
failedAttempts++;
}
}
return failedAttempts != numThreads;
}
} else {
if (numRunningThreads != numThreads) {
try {
stop();
} catch (ConnectionException e) {
e.printStackTrace();
}
return false;
} else {
return true;
}
}
System.out.println(NAME + "Http tunneling failed.");
return false;
}
private void createSender(int i, NetworkSocket socket) throws ConnectionException {
socketSenders[i] =
new NetworkSocketStreamSender(i, this, room, screenDim, blockDim, seqNumGenerator);
socketSenders[i].addListener(this);
socketSenders[i].connect(socket);
}
private void createHttpSender(int i) throws ConnectionException {
httpSenders[i] =
new NetworkHttpStreamSender(i, this, room, screenDim, blockDim, seqNumGenerator);
httpSenders[i].addListener(this);
httpSenders[i].connect(host);
}
/**
* this examines the block data queue for messages that may include the same blocks and discards
* any dupe blocks todo: refactor this nastiness
*/
private synchronized void purgeBlockDataQ() {
Message message, nextMessage;
BlockMessage blockMessage, nextBlockMessage;
Integer[] blocks, nextBlocks;
boolean skipMessage = false;
int currentMessage = 0;
LinkedBlockingQueue<Message> cloneQ =
new LinkedBlockingQueue<Message>(ScreenShareInfo.MAX_QUEUED_MESSAGES);
AtomicLong startTime = new AtomicLong(System.currentTimeMillis());
Iterator it = blockDataQ.iterator();
while (it.hasNext()) {
message = (Message) it.next();
skipMessage = false;
++currentMessage;
// we only care about block messages that are keyframes
// and have another block message after them
// to dedupe against
if (!(message.isBlockMessage() && ((BlockMessage) message).getForceKeyFrame())
&& it.hasNext()) {
continue;
}
blockMessage = (BlockMessage) message;
blocks = blockMessage.getBlocks();
// look at the next block message to see if it overlaps with this one
nextMessage = null;
while (it.hasNext()) {
nextMessage = (Message) it.next();
if (!nextMessage.isBlockMessage()) {
nextMessage = null;
continue;
}
}
// now compare the blocks between this msg and the next block message
if (nextMessage != null) {
nextBlockMessage = (BlockMessage) nextMessage;
nextBlocks = nextBlockMessage.getBlocks();
// exactly the same? ditch the whole message
if (nextBlockMessage.hasSameBlocksAs(blockMessage)) {
skipMessage = true;
} else {
// not exactly the same? See if we can prune dupe blocks
blockMessage.discardBlocksSharedWith(nextBlockMessage);
skipMessage = (nextBlockMessage.isEmpty());
}
}
// if the current message must be retained, put it on the clone queue
if (skipMessage) {
continue;
}
try {
cloneQ.put(message);
} catch (InterruptedException e) {
// System.out.println("Can't put message on clone queue");
}
}
// we've looked at the whole queue, so time to swap in clone for real queue
try {
blockDataQ.clear();
for (Message cloneMessage : cloneQ) {
blockDataQ.put(cloneMessage);
}
} catch (InterruptedException e) {
// System.out.println("Can't dump clone queue into queue");
}
}
public void send(Message message) {
try {
// force keyframe? ditch all the other messages on the queue
// since this message will overwrite everything
if (message.isBlockMessage() && ((BlockMessage) message).getForceKeyFrame()) {
blockDataQ.clear();
notifyQueueListener(0);
}
// stick message on queue
blockDataQ.put(message);
// if the queue is backed up, purge it of duplicate blocks
int qSizeInBlocks = getQueueSizeInBlocks();
if (qSizeInBlocks > ScreenShareInfo.MAX_QUEUE_SIZE_FOR_PAUSE) {
if (ScreenShareInfo.getPurgeBackedUpQueue()) {
purgeBlockDataQ();
}
notifyQueueListener(qSizeInBlocks);
}
// if we're being slow, notify also
if (ScreenShareInfo.adjustPauseFromQueueSize && perfStats.isSlow()) {
notifyPerformanceListener(true);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void start() {
System.out.println(NAME + "Starting network sender.");
if (tunneling) {
for (int i = 0; i < numRunningThreads; i++) {
httpSenders[i].sendStartStreamMessage();
executor.execute(httpSenders[i]);
}
} else {
for (int i = 0; i < numRunningThreads; i++) {
try {
socketSenders[i].sendStartStreamMessage();
executor.execute(socketSenders[i]);
} catch (ConnectionException e) {
e.printStackTrace();
}
}
}
stopped = false;
}
public void stop() throws ConnectionException {
stopped = true;
System.out.println(NAME + "Stopping network sender");
for (int i = 0; i < numRunningThreads; i++) {
if (tunneling) {
httpSenders[i].disconnect();
} else {
socketSenders[i].disconnect();
}
}
executor.shutdownNow();
httpSenders = null;
socketSenders = null;
}
private boolean tryHttpTunneling() {
NetworkHttpStreamSender httpSender =
new NetworkHttpStreamSender(0, this, room, screenDim, blockDim, seqNumGenerator);
try {
httpSender.connect(host);
return true;
} catch (ConnectionException e) {
System.out.println(NAME + "Problem connecting to " + host);
}
return false;
}
public void blockSent(int position) {
blockManager.blockSent(position);
}
public EncodedBlockData getBlockToSend(int position) {
return blockManager.getBlock(position).encode();
}
public Message getNextMessageToSend() throws InterruptedException {
try {
return blockDataQ.take();
} catch (InterruptedException e) {
if (!stopped) {
e.printStackTrace();
}
throw e;
}
}
public void networkException(int id, ExitCode reason) {
try {
numRunningThreads--;
if (tunneling) {
// httpSenders[id].disconnect();
System.out.println(NAME + "Failed to use http tunneling. Stopping.");
stop();
notifyNetworkConnectionListener(reason);
} else {
socketSenders[id].disconnect();
}
if (numRunningThreads < 1) {
System.out.println(NAME + "No more sender threads. Stopping.");
stop();
notifyNetworkConnectionListener(reason);
} else {
System.out.println(
NAME + "Sender thread stopped. " + numRunningThreads + " sender threads remaining.");
}
} catch (ConnectionException e) {
// TODO Auto-generated catch block
e.printStackTrace();
if (numRunningThreads < 1) {
System.out.println(NAME + "No more sender threads. Stopping.");
notifyNetworkConnectionListener(reason);
} else {
System.out.println(
NAME + "Sender thread stopped. " + numRunningThreads + " sender threads remaining.");
}
}
}
// utility function, remove me
private int getQueueSizeInBlocks() {
int numBlocks = 0;
for (Message message : blockDataQ) {
if (message.isBlockMessage()) {
numBlocks += ((BlockMessage) message).size();
}
}
return numBlocks;
}
}
