Adds the ability to play youtube videos.

It still needs a bit of work, but playing and pausing are operational.

add-on/background.js

@@ -1,10 +1,112 @@
 console.log("Hello from Universal Music addon!")
+const tabMessages = new Map();
+var numTabMessages = 0;
 /*
 On startup, connect to the "ping_pong" app.
 */
 var port = browser.runtime.connectNative("universalmusic");
 
+var tabPort = null;
+
+function setupTab(port)
+{
+    console.info("Tab " + port.sender.tab.url + " loaded.");
+    tabPort = port;
+    tabPort.onDisconnect.addListener(e => {
+        tabPort = null;
+        if (e.error)
+        {
+            console.error("Tab error: ", e.error)
+        }
+        else
+        {
+            console.info("Tab " + e.sender.tab.url + " disconnected.");
+        }
+        browser.tabs.remove(e.sender.tab.id);
+    });
+    tabPort.onMessage.addListener(message => {
+        if (typeof message == "object" && message.type == "response")
+        {
+            tabMessages.set(message.num, message.data);
+        }
+    });
+    return true;
+}
+
+function queryTab(message)
+{
+    let num = numTabMessages++;
+    let promise = new Promise((resolve, reject) => {
+        tabPort.postMessage({
+            num: num,
+            data: message
+        });
+        (function awaitResponse() {
+            if (tabMessages.has(num))
+            {
+                response = tabMessages.get(num);
+                tabMessages.delete(num);
+                return resolve(response);
+            }
+            else
+            {
+                setTimeout(awaitResponse, 30);
+            }
+        })();
+    });
+    tabMessages.set(numTabMessages, promise);
+    numTabMessages++;
+    return promise;
+}
+
 var listeners = [function (message, returnValue) {
+    if (typeof message == "object" && "type" in message)
+    {
+        let type = message.type;
+        lastPeriod = type.lastIndexOf(".");
+        if (lastPeriod != -1)
+        {
+            type = type.substring(lastPeriod + 1);
+        }
+        switch (type)
+        {
+        case "CommandSong":
+            returnValue = () => browser.tabs.create({url: message.song}).then(setupTab);
+            if (tabPort)
+            {
+                console.log("Replacing tab");
+                /*
+                 * Closes the existing tab first
+                 */
+                returnValue = browser.tabs.remove(e.sender.tab.id).then(returnValue);
+            }
+            else
+            {
+                console.log("Opening tab");
+                returnValue = returnValue();
+            }
+            break;
+        case "QueryStatus":
+            if (!tabPort)
+            {
+                returnValue = 4;
+                break;
+            }
+        case "QueryTime":
+        case "QueryLength":
+        case "CommandSetPlayback":
+        case "CommandSeek":
+            returnValue = queryTab(message);
+            break;
+        case "CommandQuit":
+            returnValue = quit();
+            break;
+        }
+    }
+    else if (message == "quit")
+    {
+        returnValue = quit();
+    }
     if (returnValue == null)
     {
         returnValue = "pong";
@@ -12,6 +114,17 @@ var listeners = [function (message, returnValue) {
     return returnValue;
 }];
 
+function quit()
+{
+    console.log("Quitting browser");
+    return browser.tabs.query({}).then(tabs => {
+        for (let tab of tabs)
+        {
+            browser.tabs.remove(tab.id);
+        }
+    });
+}
+
 function sleep(ms) {
     return new Promise(resolve => setTimeout(resolve, ms));
 }
@@ -20,11 +133,25 @@ function handleMessage(message)
 {
     return new Promise((resolve, reject) => {
         var returnValue = null;
-        for (index in listeners)
+        try
         {
-            returnValue = listeners[index](message, returnValue);
+            for (index in listeners)
+            {
+                returnValue = listeners[index](message, returnValue);
+            }
+            if (returnValue instanceof Promise)
+            {
+                returnValue.then(resolve).catch(reject);
+            }
+            else
+            {
+                resolve(returnValue);
+            }
+        }
+        catch (e)
+        {
+            reject(e);
         }
-        resolve(returnValue);
     })
 }
 
@@ -32,14 +159,26 @@ function handleMessage(message)
  * Listen for messages from the app.
  */
 port.onMessage.addListener((message) => {
-    console.log("Received: ", message);
+    console.log("Received from interface: ", message);
 
     handleMessage(message.message).then((response) => {
         returnValue = {
             "messageNum": message.messageNum,
-            "message": response
+            "message": {
+                "type": "edu.regis.universeplayer.browserCommands.CommandReturn",
+                "returnValue": response,
+                "confirmation": {
+                    type: "edu.regis.universeplayer.browserCommands.CommandConfirmation",
+                    message: "Done",
+                    errorCode: null
+                }
+            }
         }
         console.log("Sending ", returnValue)
         port.postMessage(returnValue);
+    }).catch(error => {
+
     });
 });
+
+browser.runtime.onConnect.addListener(setupTab);

add-on/foreground.js

@@ -0,0 +1,82 @@
+console.debug("Loading foreground.js")
+let background;
+
+function handleMessage(message)
+{
+    if (typeof message == "object" && "type" in message)
+    {
+        let type = message.type;
+        lastPeriod = type.lastIndexOf(".");
+        if (lastPeriod != -1)
+        {
+            type = type.substring(lastPeriod + 1);
+        }
+        switch (type)
+        {
+        case "QueryStatus":
+            return getState();
+        case "QueryTime":
+            return getTime();
+        case "QueryLength":
+            return getLength();
+        case "CommandSetPlayback":
+            switch (message.status)
+            {
+            case "PLAY":
+                return play();
+            case "PAUSE":
+                return pause();
+            }
+            return false;
+        case "CommandSeek":
+            return seek(message.time);
+        }
+    }
+}
+
+function sendUpdate(response)
+{
+    post = data => background.postMessage({
+        type: "update",
+        data: data
+    });
+    if (response instanceof Promise)
+    {
+        response.then(post);
+    }
+    else
+    {
+        post(response);
+    }
+}
+
+background = browser.runtime.connect({name:"universalMusic"});
+background.onMessage.addListener(message => {
+    let num = message.num;
+    response = handleMessage(message.data);
+    post = data => background.postMessage({
+        type: "response",
+        num: num,
+        data: data
+    });
+    if (response instanceof Promise)
+    {
+        response.then(post);
+    }
+    else
+    {
+        post(response);
+    }
+});
+
+if (document.readyState === "complete")
+{
+    sendUpdate("loaded");
+}
+else
+{
+    sendUpdate("loaded");
+    window.addEventListener("load", () => {
+        sendUpdate("loaded");
+    });
+}

add-on/manifest.json

@@ -22,6 +22,13 @@
     "scripts": ["background.js"]
   },
 
+  "content_scripts": [
+    {
+      "matches": ["*://*.youtube.com/watch?v=*"],
+      "js": ["foreground.js", "youtube.js"]
+    }
+  ],
+
   "browser_action": {
     "default_icon": "icon.svg"
   },

add-on/youtube.js

@@ -0,0 +1,76 @@
+console.debug("Loading youtube.js")
+var video;
+
+function onload()
+{
+    video = document.getElementsByClassName('video-stream html5-main-video')[0]
+}
+
+function getState()
+{
+    if (!video)
+    {
+        return 4;
+    }
+    else if (video.ended)
+    {
+        return 3;
+    }
+    else if (video.paused)
+    {
+        return 1;
+    }
+    else
+    {
+        return 0;
+    }
+}
+
+function getTime()
+{
+    return video.currentTime;
+}
+
+function getLength()
+{
+    return video.duration;
+}
+
+function play()
+{
+    if (video != null)
+    {
+        video.play();
+        return true;
+    }
+    return false;
+}
+
+function pause()
+{
+    if (video != null)
+    {
+        video.pause();
+        return true;
+    }
+    return false;
+}
+
+function seek(time)
+{
+    if (video != null)
+    {
+        video.currentTime = time;
+        return true;
+    }
+    return false;
+}
+
+if (document.readyState === "complete")
+{
+    onload();
+}
+else
+{
+    window.addEventListener("load", onload);
+}

addonInter/build.gradle

@@ -20,6 +20,9 @@ plugins {
 // In this section you declare where to find the dependencies of your project
 repositories {
     mavenCentral()
+    flatDir {
+        dirs new File(rootDir, 'libs')
+    }
 }
 
 // In this section you declare the dependencies for your production and test code
@@ -31,6 +34,8 @@ dependencies {
 
     implementation 'com.google.code.gson:gson:2.8.7'
 
+    implementation 'net.harawata:appdirs:1.2.1'
+
     implementation project(":browserCommands")
 
     // Declare the dependency for your favourite test framework you want to use in your tests.

addonInter/src/main/java/edu/regis/universeplayer/addon/BrowserLink.java

@@ -27,8 +27,16 @@ import java.util.HashMap;
  */
 public class BrowserLink extends MessageRunner
 {
-//    private static final Logger logger = LoggerFactory.getLogger(BrowserLink.class);
+    private static final Logger logger = LoggerFactory.getLogger(BrowserLink.class);
-    public static final Gson gson = new Gson();
+    public static final Gson gson;
+    
+    static
+    {
+        GsonBuilder builder = new GsonBuilder();
+        builder.registerTypeAdapter(StackTraceElement.class, new StackTraceElementSerializer());
+        builder.registerTypeAdapter(Throwable.class, new ThrowableSerializer());
+        gson = builder.create();
+    }
     
     /**
      * Creates a message runner.
@@ -41,8 +49,12 @@ public class BrowserLink extends MessageRunner
     @Override
     public byte[] serializeObject(Object message)
     {
-        String val = gson.toJson(message);
+        JsonElement val = gson.toJsonTree(message);
-        return val.getBytes(StandardCharsets.UTF_8);
+        if (val.isJsonObject())
+        {
+            ((JsonObject) val).addProperty("type", message.getClass().getName());
+        }
+        return val.toString().getBytes(StandardCharsets.UTF_8);
     }
     
     @Override
@@ -197,6 +209,7 @@ public class BrowserLink extends MessageRunner
             try
             {
                 clazz = Class.forName(message.getAsJsonPrimitive("type").getAsString());
+                message.remove("type");
             }
             catch (ClassNotFoundException | ClassCastException e)
             {

addonInter/src/main/java/edu/regis/universeplayer/addon/Main.java

@@ -10,7 +10,6 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
-import java.net.ServerSocket;
 import java.net.Socket;
 import java.util.LinkedList;
 import java.util.concurrent.ExecutionException;
@@ -22,23 +21,33 @@ public class Main
     
     public static void main(String[] args) throws IOException, InterruptedException
     {
-        ServerSocket socketSource = null;
-        Socket socket = null;
         MessageHandler interfaceLink;
         BrowserLink browserLink;
         Thread interfaceThread, browserThread;
+        Socket socket;
         try
         {
+            logger.debug("Connecting to browser");
+            browserLink = new BrowserLink("BrowserLink");
             try
             {
-                logger.debug("Connecting to browser");
+                logger.debug("Setting up connection");
-                browserLink = new BrowserLink("BrowserLink");
+                socket = new Socket(BrowserConstants.IP,BrowserConstants.PORT);
-                logger.debug("Setting up server");
+                logger.debug("Connection established");
-                socketSource = new ServerSocket(BrowserConstants.PORT);
+                
-                logger.debug("Server started");
+                interfaceLink = new MessageHandler("InterfaceHandler", socket.getInputStream(), socket.getOutputStream()) {
-                socket = socketSource.accept();
+                    @Override
+                    protected boolean onRun()
+                    {
+                        if (!socket.isConnected() || socket.isClosed() || socket.isInputShutdown() || socket.isOutputShutdown())
+                        {
+                            logger.debug("Socket closed, shutting down");
+                            return true;
+                        }
+                        return false;
+                    }
+                };
                 logger.debug("Connection received");
-                interfaceLink = new MessageHandler("InterfaceHandler", socket.getInputStream(), socket.getOutputStream());
                 /*
                  * Pretty much just forwards any messages to the browser and
                  * returns their value.
@@ -64,6 +73,7 @@ public class Main
             catch (IOException e)
             {
                 logger.error("Could not initialize socket", e);
+                browserLink.sendObject("quit");
                 throw e;
             }
         }
@@ -75,29 +85,6 @@ public class Main
         finally
         {
             logger.debug("Shutting down interface link");
-            if (socket != null)
-            {
-                try
-                {
-                    socket.close();
-                }
-                catch (IOException e)
-                {
-                    logger.error("Could not close socket", e);
-                }
-                finally
-                {
-                    logger.debug("Shutting down server");
-                    try
-                    {
-                        socketSource.close();
-                    }
-                    catch (IOException e)
-                    {
-                        logger.error("Could not close server", e);
-                    }
-                }
-            }
         }
     }
     

addonInter/src/main/java/edu/regis/universeplayer/addon/StackTraceElementSerializer.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2021 William Hubbard. All Rights Reserved.
+ */
+
+package edu.regis.universeplayer.addon;
+
+import com.google.gson.*;
+
+import java.lang.reflect.Type;
+
+public class StackTraceElementSerializer implements JsonSerializer<StackTraceElement>, JsonDeserializer<StackTraceElement>
+{
+    @Override
+    public JsonElement serialize(StackTraceElement src, Type typeOfSrc, JsonSerializationContext context)
+    {
+        JsonObject ob = new JsonObject();
+        ob.addProperty("loader", src.getClassLoaderName());
+        ob.addProperty("class", src.getClassName());
+        ob.addProperty("file", src.getFileName());
+        ob.addProperty("line", src.getLineNumber());
+        ob.addProperty("method", src.getMethodName());
+        ob.addProperty("module", src.getModuleName());
+        ob.addProperty("version", src.getModuleVersion());
+        return ob;
+    }
+    
+    @Override
+    public StackTraceElement deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException
+    {
+        JsonObject ob = json.getAsJsonObject();
+        return new StackTraceElement(ob.get("loader").getAsString(), ob.get("module").getAsString(), ob.get("version").getAsString(), ob.get("class").getAsString(), ob.get("method").getAsString(), ob.get("file").getAsString(), ob.get("line").getAsInt());
+    }
+}

addonInter/src/main/java/edu/regis/universeplayer/addon/ThrowableSerializer.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2021 William Hubbard. All Rights Reserved.
+ */
+
+package edu.regis.universeplayer.addon;
+
+import com.google.gson.*;
+
+import java.lang.reflect.Type;
+
+public class ThrowableSerializer implements JsonSerializer<Throwable>, JsonDeserializer<Throwable>
+{
+    @Override
+    public JsonElement serialize(Throwable src, Type typeOfSrc, JsonSerializationContext context)
+    {
+        JsonObject ob = new JsonObject();
+        ob.addProperty("message", src.getMessage());
+        ob.add("cause", context.serialize(src.getCause()));
+        JsonArray stack = new JsonArray();
+        for (StackTraceElement trace: src.getStackTrace())
+        {
+            stack.add(context.serialize(trace));
+        }
+        ob.add("trace", stack);
+        JsonArray suppressed = new JsonArray();
+        for (Throwable throwable: src.getSuppressed())
+        {
+            suppressed.add(context.serialize(throwable));
+        }
+        ob.add("suppressed", suppressed);
+        return ob;
+    }
+    
+    @Override
+    public Throwable deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException
+    {
+        JsonObject ob = json.getAsJsonObject();
+        Throwable throwable = new Throwable(ob.get("message").getAsString(), context.deserialize(ob.get("cause"), typeOfT));
+        throwable.initCause(context.deserialize(ob.get("cause"), Throwable.class));
+        JsonArray traceJson = ob.getAsJsonArray("trace");
+        StackTraceElement[] trace = new StackTraceElement[traceJson.size()];
+        for (int i = 0; i < trace.length; i++)
+        {
+            trace[i] = context.deserialize(traceJson.get(i), StackTraceElement.class);
+        }
+        throwable.setStackTrace(trace);
+        JsonArray suppressed = ob.getAsJsonArray("suppressed");
+        for (JsonElement el: suppressed)
+        {
+            throwable.addSuppressed(context.deserialize(el, Throwable.class));
+        }
+        return throwable;
+    }
+}

addonInter/src/main/resources/log4j2.xml

@@ -18,5 +18,9 @@
             <AppenderRef ref="File"/>
         </Root>
         <Logger name="edu.regis.universeplayer.browserCommands.MessageRunner" level="trace"/>
+        <Logger name="edu.regis.universeplayer.browserCommands.MessageHandler" level="trace"/>
+        <Logger name="edu.regis.universeplayer.browserCommands.memoryMapping.MemoryRunner" level="trace"/>
+        <Logger name="edu.regis.universeplayer.browserCommands.memoryMapping.MemoryHandler" level="trace"/>
+        <Logger name="edu.regis.universeplayer.addon.BrowserLink" level="trace"/>
     </Loggers>
 </Configuration>

browserCommands/build.gradle

@@ -9,6 +9,9 @@ plugins {
 // In this section you declare where to find the dependencies of your project
 repositories {
     mavenCentral()
+    flatDir {
+        dirs new File(rootDir, 'libs')
+    }
 }
 
 // In this section you declare the dependencies for your production and test code
@@ -19,6 +22,8 @@ dependencies {
     implementation 'org.apache.logging.log4j:log4j-core:2.13.3'
     implementation 'org.apache.logging.log4j:log4j-slf4j-impl:2.13.3'
 
+    implementation 'net.harawata:appdirs:1.2.1'
+
     // Declare the dependency for your favourite test framework you want to use in your tests.
     // TestNG is also supported by the Gradle Test task. Just change the
     // testCompile dependency to testCompile 'org.testng:testng:6.8.1' and add

browserCommands/src/main/java/edu/regis/universeplayer/browserCommands/BrowserConstants.java

@@ -4,14 +4,51 @@
 
 package edu.regis.universeplayer.browserCommands;
 
+import net.harawata.appdirs.AppDirsFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+
 public class BrowserConstants
 {
+    private static final Logger logger = LoggerFactory.getLogger(BrowserConstants.class);
     /**
      * The IP that the connection will be hosted on.
      */
-    public static final String IP = "127.0.0.1";
+    public static final String IP = "localhost";
     /**
      * The port both processes use for connection.
      */
     public static final int PORT = 3000;
+    
+    private static File commDir;
+    
+    /**
+     * Obtains the directory for memory mapped files
+     *
+     * @return The communications storage directory.
+     */
+    public static File getCommDir()
+    {
+        if (commDir == null)
+        {
+            commDir = new File(AppDirsFactory.getInstance().getSharedDir("universalmusic", null, null), "comm");
+            if (!commDir.getParentFile().exists())
+            {
+                if (!commDir.getParentFile().mkdir())
+                {
+                    logger.error("Could not create shared directory {}", commDir.getParent());
+                }
+            }
+            if (!commDir.exists())
+            {
+                if (!commDir.mkdir())
+                {
+                    logger.error("Could not create data directory {}", commDir);
+                }
+            }
+        }
+        return commDir;
+    }
 }

browserCommands/src/main/java/edu/regis/universeplayer/browserCommands/CommandQuit.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2021 William Hubbard. All Rights Reserved.
+ */
+
+package edu.regis.universeplayer.browserCommands;
+
+/**
+ * The quit command tells the browser to shut down.
+ *
+ * @author William Hubbard
+ * @version 0.1
+ */
+public class CommandQuit implements BrowserCommand
+{
+    public CommandQuit()
+    {
+    
+    }
+    
+    @Override
+    public String getCommandName()
+    {
+        return "quit";
+    }
+}

browserCommands/src/main/java/edu/regis/universeplayer/browserCommands/MessageHandler.java

@@ -19,20 +19,20 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 
 /**
- *
+ * Dispatches messages sent from a corresponding {@link MessageRunner}.
  */
 public class MessageHandler implements Runnable, MessageSerializer
 {
     private final Logger logger;
     
-    private final String name;
+    public final String name;
     
     private final InputStream input;
     private final OutputStream output;
     
     private final ExecutorService executor;
     private final LinkedList<MessageListener> listeners = new LinkedList<>();
-    private final HashMap<Integer, Future<Object>> messageResponses = new HashMap<>();
+    protected final HashMap<Integer, Future<Object>> messageResponses = new HashMap<>();
     
     /**
      * Creates a message handler.
@@ -56,14 +56,22 @@ public class MessageHandler implements Runnable, MessageSerializer
         return logger;
     }
     
+    /**
+     * Called at the beginning of every loop to do extra processing and check to see if we can still run.
+     *
+     * @return True if we should close the runner, false otherwise.
+     */
+    protected boolean onRun()
+    {
+        return false;
+    }
+    
     @Override
     public void run()
     {
         BufferedInputStream browserIn = null;
         BufferedOutputStream browserOut = null;
         
-        boolean running = true;
-        
         byte[][] message;
         byte[] messageByte;
         Object messageOb;
@@ -76,7 +84,7 @@ public class MessageHandler implements Runnable, MessageSerializer
             browserIn = new BufferedInputStream(this.input);
             browserOut = new BufferedOutputStream(this.output);
             
-            while (running)
+            while (!this.onRun())
             {
                 try
                 {
@@ -86,7 +94,7 @@ public class MessageHandler implements Runnable, MessageSerializer
                         if (message == null)
                         {
                             logger.info("Connection closed.");
-                            running = false;
+                            break;
                         }
                         else
                         {

browserCommands/src/main/java/edu/regis/universeplayer/browserCommands/MessageRunner.java

@@ -24,25 +24,25 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
 {
     private final Logger logger;
     
-    private final String name;
+    public final String name;
     private final InputStream input;
     private final OutputStream output;
-    private final Object readLock = new Object();
+    protected final Object readLock = new Object();
     
     /**
      * This queue serves as a cache for objects we need to send.
      */
-    private final LinkedList<MessagePacket> sendQueue = new LinkedList<>();
+    protected final LinkedList<MessagePacket> sendQueue = new LinkedList<>();
     /**
      * This queue serves as a cache for objects that are waiting for a response.
      */
-    private final HashMap<Integer, MessagePacket> sentQueue = new HashMap<>();
+    protected final HashMap<Integer, MessagePacket> sentQueue = new HashMap<>();
-    private int messagesSent = 0;
+    protected int messagesSent = 0;
     
     /**
      * Creates a message runner.
      *
-     * @param name - The name of the runner. This is used in logging.
+     * @param name   - The name of the runner. This is used in logging.
      * @param input  - The input from our external source.
      * @param output - The output to the external source.
      */
@@ -60,14 +60,22 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
         return logger;
     }
     
+    /**
+     * Called at the beginning of every loop to do extra processing and check to see if we can still run.
+     *
+     * @return True if we should close the runner, false otherwise.
+     */
+    protected boolean onRun()
+    {
+        return false;
+    }
+    
     @Override
     public void run()
     {
         BufferedInputStream browserIn = null;
         BufferedOutputStream browserOut = null;
         MessagePacket packet;
-    
-        boolean running = true;
         
         byte[][] returnMessage;
         ByteBuffer numBuffer = ByteBuffer.allocate(4);
@@ -77,7 +85,7 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
             browserIn = new BufferedInputStream(this.input);
             browserOut = new BufferedOutputStream(this.output);
             
-            while (running)
+            while (!this.onRun())
             {
                 /*
                  * Sends a messages
@@ -121,7 +129,7 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
                             if (returnMessage == null)
                             {
                                 logger.info("Connection closed.");
-                                running = false;
+                                break;
                             }
                             else
                             {
@@ -138,7 +146,7 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
                                 {
                                     packet.returnMessage = returnMessage[1];
                                     numBuffer.clear();
-                                    logger.debug("Reading message {} {}", numBuffer.getInt(), packet.returnMessage);
+                                    logger.debug("Reading message {} {}", numBuffer.getInt(), new String(packet.returnMessage, StandardCharsets.UTF_8));
                                     synchronized (this.readLock)
                                     {
                                         logger.trace("Received message {}, notifying futures.", packet.returnValue.index);
@@ -254,9 +262,9 @@ public abstract class MessageRunner implements Runnable, MessageSerializer
      */
     public class MessageFuture implements Future<Object>
     {
-        private final MessagePacket packetEntry;
+        protected final MessagePacket packetEntry;
-        private int index;
+        public int index;
-        private boolean canceled = false;
+        protected boolean canceled = false;
         
         private MessageFuture(MessagePacket packet)
         {

browserCommands/src/main/java/edu/regis/universeplayer/browserCommands/QueryStatus.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2021 William Hubbard. All Rights Reserved.
+ */
+
+package edu.regis.universeplayer.browserCommands;
+
+/**
+ * This query asks for whether a song is currently playing or not. Note that
+ * this is not the same as whether it is paused or not, as a song could have
+ * run into a playback error.
+ *
+ * @author William Hubbard
+ * @version 0.1
+ */
+public class QueryStatus implements BrowserQuery<Integer>
+{
+    @Override
+    public String getCommandName()
+    {
+        return "getStatus";
+    }
+    
+    @Override
+    public Class<Integer> getReturnType()
+    {
+        return Integer.class;
+    }
+}

interface/build.gradle

@@ -10,6 +10,9 @@ plugins {
 // In this section you declare where to find the dependencies of your project
 repositories {
     mavenCentral()
+    flatDir {
+        dirs new File(rootDir, 'libs')
+    }
 }
 
 // In this section you declare the dependencies for your production and test code

interface/src/main/java/edu/regis/universeplayer/browser/Browser.java

@@ -12,11 +12,12 @@ import edu.regis.universeplayer.data.Song;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.*;
+import java.io.File;
+import java.io.IOException;
 import java.net.ConnectException;
+import java.net.InetAddress;
+import java.net.ServerSocket;
 import java.net.Socket;
-import java.nio.ByteBuffer;
-import java.nio.charset.StandardCharsets;
 import java.util.LinkedList;
 import java.util.Scanner;
 import java.util.concurrent.*;
@@ -30,23 +31,19 @@ import java.util.concurrent.*;
 public class Browser extends MessageRunner implements Player<InternetSong>
 {
     private static final Logger logger = LoggerFactory.getLogger(Browser.class);
-    private final Socket socket;
     private final Process process;
+    private final Socket socket;
+    
+    private final LinkedList<PlaybackListener> listeners = new LinkedList<>();
+    
+    private InternetSong currentSong;
     
     public static Browser createBrowser() throws IOException, InterruptedException
     {
-        /*
+        ServerSocket server = new ServerSocket(BrowserConstants.PORT, 50, InetAddress.getByName(null));
-         * The maximum number of attempts that will be made to establish a
+        logger.debug("Server started.");
-         * connection.
+        
-         */
-        final int MAX_ATTEMPTS = 20;
-        /*
-         * How long the thread will sleep between connection attempts, in
-         * milliseconds.
-         */
-        final long SLEEP_TIME = 500;
         int startExit;
-        Socket socket = null;
         Browser browser;
         Process browserProcess = launchBrowser();
         /*
@@ -69,24 +66,31 @@ public class Browser extends MessageRunner implements Player<InternetSong>
         
         ConnectException connErr = null;
         logger.debug("Attempting connection");
-        for (int attempts = 0; socket == null && attempts < MAX_ATTEMPTS; attempts++)
+        Socket socket = server.accept();
+        if (!socket.isBound())
         {
-            try
+            logger.error("Socket not bound");
-            {
-                socket = new Socket(BrowserConstants.IP, BrowserConstants.PORT);
-            }
-            catch (ConnectException e)
-            {
-                connErr = e;
-                logger.debug("Connection attempt {} failed, trying again", attempts);
-                Thread.sleep(SLEEP_TIME);
-            }
         }
-        if (socket == null)
+        else if (!socket.isConnected())
         {
-            throw connErr;
+            logger.error("Socket not connected");
+        }
+        else if (socket.isClosed())
+        {
+            logger.error("Socket prematurely closed");
+        }
+        else if (socket.isInputShutdown())
+        {
+            logger.error("Socket input prematurely closed.");
+        }
+        else if (socket.isOutputShutdown())
+        {
+            logger.error("Socket input prematurely closed.");
+        }
+        else
+        {
+            logger.debug("Connection established.");
         }
-        logger.debug("Browser connection established.");
         browser = new Browser(socket, browserProcess);
         return browser;
     }
@@ -98,6 +102,17 @@ public class Browser extends MessageRunner implements Player<InternetSong>
         this.process = process;
     }
     
+    @Override
+    protected boolean onRun()
+    {
+        if (!socket.isConnected() || socket.isClosed() || socket.isInputShutdown() || socket.isOutputShutdown())
+        {
+            logger.debug("Socket closed, shutting down");
+            return true;
+        }
+        return false;
+    }
+    
     /**
      * Utility method for launching a browser instance
      *
@@ -155,7 +170,7 @@ public class Browser extends MessageRunner implements Player<InternetSong>
     @Override
     public Song getCurrentSong()
     {
-        return null;
+        return this.currentSong;
     }
     
     @Override
@@ -178,23 +193,28 @@ public class Browser extends MessageRunner implements Player<InternetSong>
     @Override
     public QueryFuture<Void> close()
     {
-        if (process != null)
-        {
-            logger.info("Destroying browser processes {}, {}", process, process.descendants().toArray(ProcessHandle[]::new));
-            process.descendants().forEach(ProcessHandle::destroy);
-            process.destroy();
-        }
-        else
-        {
-            logger.info("Process already destroyed.");
-        }
         try
         {
-            this.socket.close();
+            QueryFuture<Void> future = new ForwardedFuture(this.sendObject(new CommandQuit()));
+            return future;
         }
         catch (IOException e)
         {
-            logger.error("Could not close browser socket", e);
+            logger.error("Could not deliver quit command", e);
+            logger.error("Destroying browser processes {}, {}", process, process.descendants().toArray(ProcessHandle[]::new));
+            try
+            {
+                socket.close();
+            }
+            catch (IOException ex)
+            {
+                logger.error("Could not close socket", ex);
+            }
+            finally
+            {
+                process.descendants().forEach(ProcessHandle::destroy);
+                process.destroy();
+            }
         }
         return null;
     }
@@ -236,19 +256,43 @@ public class Browser extends MessageRunner implements Player<InternetSong>
     @Override
     public QueryFuture<Void> play()
     {
-        return null;
+        try
+        {
+            return new ForwardedFuture(this.sendObject(new CommandSetPlayback(CommandSetPlayback.Playback.PLAY)));
+        }
+        catch (IOException e)
+        {
+            logger.error("Could not send message", e);
+            return null;
+        }
     }
     
     @Override
     public QueryFuture<Void> pause()
     {
-        return null;
+        try
+        {
+            return new ForwardedFuture(this.sendObject(new CommandSetPlayback(CommandSetPlayback.Playback.PAUSE)));
+        }
+        catch (IOException e)
+        {
+            logger.error("Could not send message", e);
+            return null;
+        }
     }
     
     @Override
     public QueryFuture<Void> togglePlayback()
     {
-        return null;
+        try
+        {
+            return new ForwardedFuture(this.sendObject(new CommandSetPlayback(CommandSetPlayback.Playback.PAUSE)));
+        }
+        catch (IOException e)
+        {
+            logger.error("Could not send message", e);
+            return null;
+        }
     }
 
     /**
@@ -263,7 +307,15 @@ public class Browser extends MessageRunner implements Player<InternetSong>
     @Override
     public QueryFuture<Void> seek(float time)
     {
-        return null;
+        try
+        {
+            return new ForwardedFuture(this.sendObject(new CommandSeek(time)));
+        }
+        catch (IOException e)
+        {
+            logger.error("Could not send message", e);
+            return null;
+        }
     }
 
     /**
@@ -274,7 +326,71 @@ public class Browser extends MessageRunner implements Player<InternetSong>
     @Override
     public QueryFuture<PlaybackStatus> getStatus()
     {
-        return null;
+        try
+        {
+            Future future = this.sendObject(new QueryStatus());
+            return new QueryFuture<>() {
+                
+                private CommandReturn<Double> getVal() throws ExecutionException, InterruptedException
+                {
+                    return ((CommandReturn<Double>) future.get());
+                }
+    
+                private CommandReturn<Double> getVal(long timeout, TimeUnit unit) throws ExecutionException, InterruptedException, TimeoutException
+                {
+                    return ((CommandReturn<Double>) future.get(timeout, unit));
+                }
+    
+                @Override
+                public CommandConfirmation getConfirmation() throws CancellationException, ExecutionException, InterruptedException
+                {
+                    return this.getVal().getConfirmation();
+                }
+    
+                @Override
+                public CommandConfirmation getConfirmation(long timeout, TimeUnit unit) throws ExecutionException, InterruptedException, TimeoutException
+                {
+                    return this.getVal(timeout, unit).getConfirmation();
+                }
+    
+                @Override
+                public boolean cancel(boolean mayInterruptIfRunning)
+                {
+                    return future.cancel(mayInterruptIfRunning);
+                }
+    
+                @Override
+                public boolean isCancelled()
+                {
+                    return future.isCancelled();
+                }
+    
+                @Override
+                public boolean isDone()
+                {
+                    return future.isDone();
+                }
+    
+                @Override
+                public PlaybackStatus get() throws InterruptedException, ExecutionException
+                {
+                    Double value = getVal().getReturnValue();
+                    return PlaybackStatus.values()[value.intValue()];
+                }
+    
+                @Override
+                public PlaybackStatus get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException
+                {
+                    Double value = getVal(timeout, unit).getReturnValue();
+                    return PlaybackStatus.values()[value.intValue()];
+                }
+            };
+        }
+        catch (IOException e)
+        {
+            logger.error("Could not send message", e);
+            return null;
+        }
     }
     
     @Override

interface/src/main/java/edu/regis/universeplayer/localPlayer/LocalPlayer.java

@@ -4,7 +4,6 @@
 package edu.regis.universeplayer.localPlayer;
 
 import com.intervigil.wave.WaveReader;
-
 import edu.regis.universeplayer.PlaybackListener;
 import edu.regis.universeplayer.PlaybackStatus;
 import edu.regis.universeplayer.Player;
@@ -12,6 +11,8 @@ import edu.regis.universeplayer.browserCommands.CommandConfirmation;
 import edu.regis.universeplayer.browserCommands.QueryFuture;
 import edu.regis.universeplayer.data.LocalSong;
 import edu.regis.universeplayer.data.Song;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import uk.co.caprica.vlcj.factory.MediaPlayerFactory;
 import uk.co.caprica.vlcj.media.MediaRef;
 import uk.co.caprica.vlcj.media.TrackType;
@@ -19,17 +20,12 @@ import uk.co.caprica.vlcj.player.base.MediaPlayer;
 import uk.co.caprica.vlcj.player.base.MediaPlayerEventListener;
 import uk.co.caprica.vlcj.player.base.StatusApi;
 import uk.co.caprica.vlcj.player.component.AudioPlayerComponent;
-import uk.co.caprica.vlcj.player.component.EmbeddedMediaPlayerComponent;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import javax.swing.*;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
-import java.io.InputStream;
 import java.util.LinkedList;
 import java.util.concurrent.*;
 

interface/src/main/java/edu/regis/universeplayer/player/Interface.java

@@ -6,6 +6,7 @@ package edu.regis.universeplayer.player;
 
 import edu.regis.universeplayer.Player;
 import edu.regis.universeplayer.browser.Browser;
+import edu.regis.universeplayer.browser.InternetSong;
 import edu.regis.universeplayer.data.Queue;
 import edu.regis.universeplayer.data.*;
 import edu.regis.universeplayer.localPlayer.LocalPlayer;
@@ -36,6 +37,7 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
     private static final Logger logger = LoggerFactory.getLogger(Interface.class);
     
     private static File dataDir;
+    private static File commDir;
     private static File configDir;
     
     /**
@@ -94,29 +96,32 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
                 inter.players.add(browser = Browser.createBrowser());
                 browserThread = new Thread(browser);
                 browserThread.start();
+                logger.debug("Sending ping");
+                browser.sendObject("ping");
                 Runtime.getRuntime().addShutdownHook(new Thread(browser::close));
+                Player.REGISTERED_PLAYERS.put(InternetSong.class, browser);
                 
-                LinkedList<Future<Object>> pingRequests = new LinkedList<>();
+//                LinkedList<Future<Object>> pingRequests = new LinkedList<>();
-                for (int i = 0; i < 20; i++)
+//                for (int i = 0; i < 20; i++)
-                {
+//                {
-                    logger.info("Sending ping");
+//                    logger.info("Sending ping");
-                    pingRequests.add(browser.sendObject("ping"));
+//                    pingRequests.add(browser.sendObject("ping"));
-                }
+//                }
-                
+//
-                LinkedList<Future<Object>> toRemove = new LinkedList<>();
+//                LinkedList<Future<Object>> toRemove = new LinkedList<>();
-                while (pingRequests.size() > 0)
+//                while (pingRequests.size() > 0)
-                {
+//                {
-                    for (Future<Object> future : pingRequests)
+//                    for (Future<Object> future : pingRequests)
-                    {
+//                    {
-                        if (future.isDone())
+//                        if (future.isDone())
-                        {
+//                        {
-                            logger.info("Receiving {}", future.get());
+//                            logger.info("Receiving {}", future.get());
-                            toRemove.add(future);
+//                            toRemove.add(future);
-                        }
+//                        }
-                    }
+//                    }
-                    pingRequests.removeAll(toRemove);
+//                    pingRequests.removeAll(toRemove);
-                    toRemove.clear();
+//                    toRemove.clear();
-                }
+//                }
             }
             catch (IOException e)
             {
@@ -173,6 +178,33 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
         return configDir;
     }
     
+    /**
+     * Obtains the directory for memory mapped files
+     * @return The communications storage directory.
+     */
+    public static File getCommDir()
+    {
+        if (commDir == null)
+        {
+            commDir = new File(AppDirsFactory.getInstance().getSharedDir("universalmusic", null, null), "comm");
+            if (!commDir.getParentFile().exists())
+            {
+                if (!commDir.getParentFile().mkdir())
+                {
+                    logger.error("Could not create shared directory {}", commDir.getParent());
+                }
+            }
+            if (!commDir.exists())
+            {
+                if (!commDir.mkdir())
+                {
+                    logger.error("Could not create data directory {}", commDir);
+                }
+            }
+        }
+        return commDir;
+    }
+    
     /**
      * Creates an interface
      */

interface/src/main/java/edu/regis/universeplayer/player/PlayerControls.java

@@ -12,6 +12,7 @@ import edu.regis.universeplayer.data.Song;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import javax.swing.*;
 import java.awt.*;
 import java.awt.event.FocusAdapter;
 import java.awt.event.FocusEvent;
@@ -21,8 +22,6 @@ import java.util.LinkedList;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ForkJoinPool;
 
-import javax.swing.*;
-
 /**
  * This panel contains the buttons necessary for controlling the playback of audio.
  *

interface/src/main/resources/log4j2.xml

@@ -20,6 +20,8 @@
         <Logger name="edu.regis.universeplayer.data.LocalSongProvider" level="debug">
             <AppenderRef ref="Console"/>
         </Logger>
+        <Logger name="edu.regis.universeplayer.browserCommands.memoryMapping.MemoryRunner" level="trace"/>
+        <Logger name="edu.regis.universeplayer.browserCommands.memoryMapping.MemoryHandler" level="trace"/>
 <!--        <Logger name="edu.regis.universeplayer.localPlayer.LocalPlayer" level="debug">-->
 <!--            <AppenderRef ref="Console"/>-->
 <!--        </Logger>-->