Merge branch 'milestone1'

src/ve/ucv/ciens/ccg/nxtar/Main.java

@@ -1,66 +0,0 @@
-package ve.ucv.ciens.ccg.nxtar;
-
-import com.badlogic.gdx.ApplicationListener;
-import com.badlogic.gdx.Gdx;
-import com.badlogic.gdx.graphics.GL10;
-import com.badlogic.gdx.graphics.OrthographicCamera;
-import com.badlogic.gdx.graphics.Texture;
-import com.badlogic.gdx.graphics.Texture.TextureFilter;
-import com.badlogic.gdx.graphics.g2d.Sprite;
-import com.badlogic.gdx.graphics.g2d.SpriteBatch;
-import com.badlogic.gdx.graphics.g2d.TextureRegion;
-
-public class Main implements ApplicationListener {
-	private OrthographicCamera camera;
-	private SpriteBatch batch;
-	private Texture texture;
-	private Sprite sprite;
-
-	@Override
-	public void create() {		
-		float w = Gdx.graphics.getWidth();
-		float h = Gdx.graphics.getHeight();
-
-		camera = new OrthographicCamera(1, h/w);
-		batch = new SpriteBatch();
-
-		texture = new Texture(Gdx.files.internal("data/libgdx.png"));
-		texture.setFilter(TextureFilter.Linear, TextureFilter.Linear);
-
-		TextureRegion region = new TextureRegion(texture, 0, 0, 512, 275);
-
-		sprite = new Sprite(region);
-		sprite.setSize(0.9f, 0.9f * sprite.getHeight() / sprite.getWidth());
-		sprite.setOrigin(sprite.getWidth()/2, sprite.getHeight()/2);
-		sprite.setPosition(-sprite.getWidth()/2, -sprite.getHeight()/2);
-	}
-
-	@Override
-	public void dispose() {
-		batch.dispose();
-		texture.dispose();
-	}
-
-	@Override
-	public void render() {		
-		Gdx.gl.glClearColor(1, 1, 1, 1);
-		Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
-
-		batch.setProjectionMatrix(camera.combined);
-		batch.begin();
-		sprite.draw(batch);
-		batch.end();
-	}
-
-	@Override
-	public void resize(int width, int height) {
-	}
-
-	@Override
-	public void pause() {
-	}
-
-	@Override
-	public void resume() {
-	}
-}

src/ve/ucv/ciens/ccg/nxtar/NxtARCore.java

@@ -0,0 +1,120 @@
+package ve.ucv.ciens.ccg.nxtar;
+
+import ve.ucv.ciens.ccg.nxtar.interfaces.MulticastEnabler;
+import ve.ucv.ciens.ccg.nxtar.interfaces.NetworkConnectionListener;
+import ve.ucv.ciens.ccg.nxtar.interfaces.Toaster;
+import ve.ucv.ciens.ccg.nxtar.network.RobotControlThread;
+import ve.ucv.ciens.ccg.nxtar.network.ServiceDiscoveryThread;
+import ve.ucv.ciens.ccg.nxtar.network.VideoStreamingThread;
+import ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants;
+
+import com.badlogic.gdx.Application;
+import com.badlogic.gdx.ApplicationListener;
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.graphics.GL10;
+import com.badlogic.gdx.graphics.OrthographicCamera;
+import com.badlogic.gdx.graphics.Texture;
+import com.badlogic.gdx.graphics.Texture.TextureFilter;
+import com.badlogic.gdx.graphics.g2d.Sprite;
+import com.badlogic.gdx.graphics.g2d.SpriteBatch;
+import com.badlogic.gdx.graphics.g2d.TextureRegion;
+
+public class NxtARCore implements ApplicationListener, NetworkConnectionListener {
+	private static final String TAG = "NXTAR_CORE_MAIN";
+	private static final String CLASS_NAME = NxtARCore.class.getSimpleName();
+
+	private OrthographicCamera camera;
+	private SpriteBatch batch;
+	private Texture texture;
+	private Sprite sprite;
+	private Toaster toaster;
+	private MulticastEnabler mcastEnabler;
+	private int connections;
+
+	private ServiceDiscoveryThread udpThread;
+	private VideoStreamingThread videoThread;
+	private RobotControlThread robotThread;
+
+	public NxtARCore(Application concreteApp){
+		super();
+		connections = 0;
+		try{
+			this.toaster = (Toaster)concreteApp;
+			this.mcastEnabler = (MulticastEnabler)concreteApp;
+		}catch(ClassCastException cc){
+			Gdx.app.debug(TAG, CLASS_NAME + ".Main() :: concreteApp does not implement any of the required interfaces.");
+			System.exit(ProjectConstants.EXIT_FAILURE);
+		}
+	}
+
+	@Override
+	public void create(){
+		float w = Gdx.graphics.getWidth();
+		float h = Gdx.graphics.getHeight();
+
+		Gdx.app.setLogLevel(Application.LOG_DEBUG);
+
+		camera = new OrthographicCamera(1, h/w);
+		batch = new SpriteBatch();
+
+		texture = new Texture(Gdx.files.internal("data/libgdx.png"));
+		texture.setFilter(TextureFilter.Linear, TextureFilter.Linear);
+
+		TextureRegion region = new TextureRegion(texture, 0, 0, 512, 275);
+
+		sprite = new Sprite(region);
+		sprite.setSize(0.9f, 0.9f * sprite.getHeight() / sprite.getWidth());
+		sprite.setOrigin(sprite.getWidth()/2, sprite.getHeight()/2);
+		sprite.setPosition(-sprite.getWidth()/2, -sprite.getHeight()/2);
+
+		Gdx.app.debug(TAG, CLASS_NAME + ".create() :: Creating network threads");
+		mcastEnabler.enableMulticast();
+		udpThread = ServiceDiscoveryThread.getInstance();
+		videoThread = VideoStreamingThread.getInstance().setToaster(toaster);
+		robotThread = RobotControlThread.getInstance().setToaster(toaster);
+
+		udpThread.start();
+		videoThread.start();
+		robotThread.start();
+	}
+
+	@Override
+	public void dispose() {
+		batch.dispose();
+		texture.dispose();
+	}
+
+	@Override
+	public void render(){
+		Gdx.gl.glClearColor(1, 1, 1, 1);
+		Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
+
+		batch.setProjectionMatrix(camera.combined);
+		batch.begin();
+		sprite.draw(batch);
+		batch.end();
+	}
+
+	@Override
+	public void resize(int width, int height){
+	}
+
+	@Override
+	public void pause(){
+	}
+
+	@Override
+	public void resume(){
+	}
+
+	@Override
+	public synchronized void networkStreamConnected(String streamName){
+		if(streamName.compareTo(VideoStreamingThread.THREAD_NAME) == 0 || streamName.compareTo(RobotControlThread.THREAD_NAME) == 0)
+			connections += 1;
+		if(connections >= 2){
+			Gdx.app.debug(TAG, CLASS_NAME + ".networkStreamConnected() :: Stopping service broadcast.");
+			udpThread.finish();
+			mcastEnabler.disableMulticast();
+		}
+	}
+}

src/ve/ucv/ciens/ccg/nxtar/interfaces/MulticastEnabler.java

@@ -0,0 +1,6 @@
+package ve.ucv.ciens.ccg.nxtar.interfaces;
+
+public interface MulticastEnabler {
+	public void enableMulticast();
+	public void disableMulticast();
+}

src/ve/ucv/ciens/ccg/nxtar/interfaces/NetworkConnectionListener.java

@@ -0,0 +1,5 @@
+package ve.ucv.ciens.ccg.nxtar.interfaces;
+
+public interface NetworkConnectionListener {
+	public void networkStreamConnected(String streamName);
+}

src/ve/ucv/ciens/ccg/nxtar/interfaces/Toaster.java

@@ -0,0 +1,6 @@
+package ve.ucv.ciens.ccg.nxtar.interfaces;
+
+public interface Toaster {
+	public void showShortToast(String msg);
+	public void showLongToast(String msg);
+}

src/ve/ucv/ciens/ccg/nxtar/network/RobotControlThread.java

@@ -0,0 +1,64 @@
+package ve.ucv.ciens.ccg.nxtar.network;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+import ve.ucv.ciens.ccg.nxtar.interfaces.NetworkConnectionListener;
+import ve.ucv.ciens.ccg.nxtar.interfaces.Toaster;
+import ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants;
+
+import com.badlogic.gdx.Gdx;
+
+public class RobotControlThread extends Thread {
+	public static final String THREAD_NAME = "RobotControlThread";
+	private static final String TAG = "NXTAR_CORE_ROBOTTHREAD";
+	private static final String CLASS_NAME = RobotControlThread.class.getSimpleName();
+
+	private NetworkConnectionListener netListener;
+	private ServerSocket server;
+	private Socket client;
+	private Toaster toaster;
+
+	private RobotControlThread(){
+		super(THREAD_NAME);
+
+		netListener = null;
+
+		try{
+			server = new ServerSocket(ProjectConstants.SERVER_TCP_PORT_2);
+		}catch(IOException io){
+			Gdx.app.error(TAG, CLASS_NAME + ".RobotControlThread() :: Error creating server: " + io.getMessage(), io);
+		}
+	}
+	
+	private static class SingletonHolder{
+		public static final RobotControlThread INSTANCE = new RobotControlThread();
+	}
+
+	public static RobotControlThread getInstance(){
+		return SingletonHolder.INSTANCE;
+	}
+
+	public RobotControlThread setToaster(Toaster toaster){
+		this.toaster = toaster;
+		return this;
+	}
+
+	public void addNetworkConnectionListener(NetworkConnectionListener listener){
+		netListener = listener;
+	}
+
+	@Override
+	public void run(){
+		try{
+			client = server.accept();
+			if(netListener != null)
+				netListener.networkStreamConnected(THREAD_NAME);
+			toaster.showShortToast("Client connected to RobotControlThread");
+			client.close();
+		}catch(IOException io){
+			Gdx.app.error(TAG, CLASS_NAME + ".run() :: Error accepting client: " + io.getMessage(), io);
+		}
+	}
+}

src/ve/ucv/ciens/ccg/nxtar/network/ServiceDiscoveryThread.java

@@ -0,0 +1,162 @@
+package ve.ucv.ciens.ccg.nxtar.network;
+
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+import ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants;
+
+import com.badlogic.gdx.Gdx;
+
+/**
+ * Ad hoc service discovery server thread.
+ * 
+ * <p> This thread performs an ad hoc service discovery protocol. A multicast datagram packet is sent every
+ * 250 miliseconds carrying the string "NxtAR server is here!" on the multicast address defined 
+ * in {@link ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants#MULTICAST_ADDRESS}. The port defined in
+ * {@link ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants#SERVER_UDP_PORT} is used for the transmissions. The server stops
+ * when another thread calls the {@link #finish()} method or the server fails to transmit {@link #MAX_RETRIES} packets in
+ * a row, whichever happens first.</p>
+ * 
+ * @author miky
+ */
+public class ServiceDiscoveryThread extends Thread {
+	/**
+	 * The name used to identify this thread.
+	 */
+	public static final String THREAD_NAME = "ServiceDiscoveryThread";
+	/**
+	 * Tag used for logging.
+	 */
+	private static final String TAG = "NXTAR_CORE_UDPTHREAD";
+	/**
+	 * Class name used for logging.
+	 */
+	private static final String CLASS_NAME = ServiceDiscoveryThread.class.getSimpleName();
+	/**
+	 * Maximum number of transmission attempts before ending the thread abruptly.
+	 */
+	private static final int MAX_RETRIES = 5;
+
+	/**
+	 * A semaphore object used to synchronize acces to this thread finish flag.
+	 */
+	private Object semaphore;
+	/**
+	 * The finish flag.
+	 */
+	private boolean done;
+	/**
+	 * The UDP server socket used for the ad hoc service discovery protocol.
+	 */
+	private DatagramSocket udpServer;
+	/**
+	 * Holder for the multicast address used in the protocol.
+	 */
+	private InetAddress group;
+
+	private ServiceDiscoveryThread(){
+		// Setup this thread name.
+		super(THREAD_NAME);
+
+		done = false;
+		semaphore = new Object();
+
+		// Try to get the InetAddress defined by the IP address defined in ProjectConstants.MULTICAST_ADDRESS.
+		try{
+			group = InetAddress.getByName(ProjectConstants.MULTICAST_ADDRESS);
+		}catch(UnknownHostException uh){
+			group = null;
+		}
+
+		// Create a UDP socket at the port defined in ProjectConstants.SERVER_UDP_PORT.
+		Gdx.app.debug(TAG, CLASS_NAME + ".ServiceDiscoveryThread() :: Creating multicast server.");
+		try{
+			udpServer = new DatagramSocket(ProjectConstants.SERVER_UDP_PORT);
+		}catch(IOException io){
+			Gdx.app.error(TAG, CLASS_NAME + ".ServiceDiscoveryThread() :: Error creating UDP socket: " + io.getMessage());
+			udpServer = null;
+		}
+		Gdx.app.debug(TAG, CLASS_NAME + ".ServiceDiscoveryThread() :: Multicast server created.");
+	}
+
+	/**
+	 * Singleton holder for this class.
+	 */
+	private static class SingletonHolder{
+		public static final ServiceDiscoveryThread INSTANCE = new ServiceDiscoveryThread();
+	}
+
+	/**
+	 * Get the singleton instance of this class.
+	 * 
+	 * @return The singleton instance.
+	 */
+	public static ServiceDiscoveryThread getInstance(){
+		return SingletonHolder.INSTANCE;
+	}
+
+	/**
+	 * This thread's run method.
+	 * 
+	 * <p>This method executes the ad hoc service discovery protocol implemented by this class, as
+	 * described in the class introduction.</p>
+	 */
+	@Override
+	public void run(){
+		int retries = 0;
+		byte[] buffer = (new String("NxtAR server here!")).getBytes();
+
+		// If failed to get any of the required network elements then end the thread right away.
+		if(group == null || udpServer == null){
+			Gdx.app.error(TAG, CLASS_NAME + ".run() :: No multicast address defined, ending thread.");
+			return;
+		}
+		if(group == null){
+			Gdx.app.error(TAG, CLASS_NAME + ".run() :: No server available, ending thread.");
+			return;
+		}
+
+		while(true){
+			// Verify if the thread should end. If that is the case, close the server.
+			synchronized(semaphore){
+				if(done){
+					udpServer.close();
+					break;
+				}
+			}
+			try{
+				// End the thread if already at the last retry attempt after too many failed transmissions.
+				if(retries >= MAX_RETRIES){
+					Gdx.app.error(TAG, CLASS_NAME + ".run() :: Too many failed transmissions, ending thread.");
+					udpServer.close();
+					break;
+				}
+				// Send the packet and reset the retry counter.
+				DatagramPacket packet = new DatagramPacket(buffer, buffer.length, group, ProjectConstants.SERVER_UDP_PORT);
+				udpServer.send(packet);
+				retries = 0;
+				try{ sleep(250L); }catch(InterruptedException ie){ }
+			}catch(IOException io){
+				Gdx.app.error(TAG, CLASS_NAME + ".run() :: Error sending packet: " + io.getMessage());
+				retries += 1;
+			}
+		}
+		if(retries < MAX_RETRIES)
+			Gdx.app.debug(TAG, CLASS_NAME + ".run() :: Service discovery successfully terminated.");
+		else
+			Gdx.app.debug(TAG, CLASS_NAME + ".run() :: Service discovery terminated after too many failed transmissions.");
+	}
+
+	/**
+	 * Marks this thread as ready to end.
+	 */
+	public void finish(){
+		synchronized(semaphore){
+			Gdx.app.debug(TAG, CLASS_NAME + ".finish() :: Finishing service discovery thread.");
+			done = true;
+		}
+	}
+}

src/ve/ucv/ciens/ccg/nxtar/network/VideoStreamingThread.java

@@ -0,0 +1,63 @@
+package ve.ucv.ciens.ccg.nxtar.network;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+import ve.ucv.ciens.ccg.nxtar.interfaces.NetworkConnectionListener;
+import ve.ucv.ciens.ccg.nxtar.interfaces.Toaster;
+import ve.ucv.ciens.ccg.nxtar.utils.ProjectConstants;
+
+import com.badlogic.gdx.Gdx;
+
+public class VideoStreamingThread extends Thread {
+	public static final String THREAD_NAME = "VideoStreamingThread";
+	private static final String TAG = "NXTAR_CORE_VIDEOTHREAD";
+	private static final String CLASS_NAME = VideoStreamingThread.class.getSimpleName();
+
+	private NetworkConnectionListener netListener;
+	private ServerSocket server;
+	private Socket client;
+	private Toaster toaster;
+
+	private VideoStreamingThread(){
+		super(THREAD_NAME);
+
+		netListener = null;
+		try{
+			server = new ServerSocket(ProjectConstants.SERVER_TCP_PORT_1);
+		}catch(IOException io){
+			Gdx.app.error(TAG, CLASS_NAME + ".VideoStreamingThread() :: Error creating server: " + io.getMessage(), io);
+		}
+	}
+
+	private static class SingletonHolder{
+		public static final VideoStreamingThread INSTANCE = new VideoStreamingThread();
+	}
+
+	public static VideoStreamingThread getInstance(){
+		return SingletonHolder.INSTANCE;
+	}
+
+	public VideoStreamingThread setToaster(Toaster toaster){
+		this.toaster = toaster;
+		return this;
+	}
+
+	public void addNetworkConnectionListener(NetworkConnectionListener listener){
+		netListener = listener;
+	}
+
+	@Override
+	public void run(){
+		try{
+			client = server.accept();
+			if(netListener != null)
+				netListener.networkStreamConnected(THREAD_NAME);
+			toaster.showShortToast("Client connected to VideoStreamingThread");
+			client.close();
+		}catch(IOException io){
+			Gdx.app.error(TAG, CLASS_NAME + ".run() :: Error accepting client: " + io.getMessage(), io);
+		}
+	}
+}

src/ve/ucv/ciens/ccg/nxtar/utils/ProjectConstants.java

@@ -0,0 +1,12 @@
+package ve.ucv.ciens.ccg.nxtar.utils;
+
+public abstract class ProjectConstants {
+	public static final int SERVER_UDP_PORT = 8889;
+	public static final int SERVER_TCP_PORT_1 = 9989;
+	public static final int SERVER_TCP_PORT_2 = 9990;
+	public static final String MULTICAST_ADDRESS = "230.0.0.1";
+	public static final int EXIT_SUCCESS = 0;
+	public static final int EXIT_FAILURE = 1;
+
+	public static final boolean DEBUG = true;
+}