Merge pull request #933 from smartdevicelink/bugfix/usb_enhacements

usb enhacements

8 files changed, 251 insertions, 76 deletions

diff --git a/sdl_android/src/main/java/com/smartdevicelink/protocol/SdlProtocol.java b/sdl_android/src/main/java/com/smartdevicelink/protocol/SdlProtocol.java
index f97e8403c..7f223d1ce 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/protocol/SdlProtocol.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/protocol/SdlProtocol.java
@@ -1147,7 +1147,7 @@ public class SdlProtocol {
                 activeTransports.remove(SessionType.PCM);
             }
 
-            if(disconnectedTransport.equals(getTransportForSession(SessionType.RPC))){
+            if(disconnectedTransport.equals(getTransportForSession(SessionType.RPC)) || disconnectedTransport.equals(connectedPrimaryTransport)){
                 //transportTypes.remove(type);
                 boolean primaryTransportAvailable = false;
                 if(requestedPrimaryTransports != null && requestedPrimaryTransports.size() > 1){
@@ -1161,6 +1161,7 @@ public class SdlProtocol {
                         }
                     }
                 }
+                connectedPrimaryTransport = null;
                 transportManager.close(iSdlProtocol.getSessionId());
                 transportManager = null;
                 requestedSession = false;
diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/MultiplexUsbTransport.java b/sdl_android/src/main/java/com/smartdevicelink/transport/MultiplexUsbTransport.java
index e807f7ac7..7ebcec1c2 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/MultiplexUsbTransport.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/MultiplexUsbTransport.java
@@ -62,7 +62,8 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
     private final Bundle deviceInfo;
     private ReaderThread readerThread;
     private WriterThread writerThread;
-    private final ParcelFileDescriptor parcelFileDescriptor;
+    private ParcelFileDescriptor parcelFileDescriptor;
+    private Boolean connectionSuccessful = null;
 
     MultiplexUsbTransport(ParcelFileDescriptor parcelFileDescriptor, Handler handler, Bundle bundle){
         super(handler, TransportType.USB);
@@ -99,9 +100,18 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
     public synchronized void start(){
         setState(STATE_CONNECTING);
         FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
+        if(fileDescriptor == null || !fileDescriptor.valid()){
+            Log.e(TAG, "USB FD was null or not valid,");
+            setState(STATE_NONE);
+            return;
+        }
         readerThread = new ReaderThread(fileDescriptor);
+        readerThread.setDaemon(true);
         writerThread = new WriterThread(fileDescriptor);
+        writerThread.setDaemon(true);
 
+        readerThread.start();
+        writerThread.start();
 
         // Send the name of the connected device back to the UI Activity
         Message msg = handler.obtainMessage(SdlRouterService.MESSAGE_DEVICE_NAME);
@@ -112,29 +122,33 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
         handler.sendMessage(msg);
 
         setState(STATE_CONNECTED);
-        readerThread.start();
-        writerThread.start();
     }
 
     protected synchronized void stop(int stateToTransitionTo) {
         //Log.d(TAG, "Attempting to close the Usb transports");
         if (writerThread != null) {
             writerThread.cancel();
+            writerThread.interrupt();
             writerThread = null;
         }
 
         if (readerThread != null) {
             readerThread.cancel();
+            readerThread.interrupt();
             readerThread = null;
         }
 
-        if(parcelFileDescriptor != null){
+        if( (connectionSuccessful== null || connectionSuccessful == true )      //else, the connection was bad. Not closing the PFD helps recover
+                && parcelFileDescriptor != null){
             try {
                 parcelFileDescriptor.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
+        parcelFileDescriptor = null;
+
+        System.gc();
 
         setState(stateToTransitionTo);
     }
@@ -182,8 +196,12 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
         bundle.putString(LOG, "Device connection was lost");
         msg.setData(bundle);
         handler.sendMessage(msg);
-        stop();
-
+        handler.postDelayed(new Runnable() { //sends this stop back to the main thread to exit the reader thread
+            @Override
+            public void run() {
+                stop();
+            }
+        }, 250);
     }
 
     private class ReaderThread extends Thread{
@@ -199,7 +217,7 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
         @Override
         public void run() {             //FIXME probably check to see what the BT does
             super.run();
-            final int READ_BUFFER_SIZE = 4096;
+            final int READ_BUFFER_SIZE = 16384;
             byte[] buffer = new byte[READ_BUFFER_SIZE];
             int bytesRead;
             boolean stateProgress;
@@ -221,6 +239,9 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
                         Log.w(TAG,"Read some data, but thread is interrupted");
                         return;
                     }
+                    if(connectionSuccessful != null && connectionSuccessful == false){
+                        connectionSuccessful = true;
+                    }
                     byte input;
                     for(int i=0;i<bytesRead; i++){
                         input=buffer[i];
@@ -284,12 +305,11 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
         public WriterThread(FileDescriptor fileDescriptor) {
             //Log.d(TAG, "Creating a Connected - Write Thread");
             OutputStream tmpOut = null;
-            setName("SDL Router BT Write Thread");
+            setName("SDL USB Write Thread");
             // Get the Usb output streams
             mmOutStream = new FileOutputStream(fileDescriptor);
-
-
         }
+
         /**
          * Write to the connected OutStream.
          * @param buffer  The bytes to write
@@ -302,6 +322,9 @@ public class MultiplexUsbTransport extends MultiplexBaseTransport{
                 }
                 //This would be a good spot to log out all bytes received
                 mmOutStream.write(buffer, offset, count);
+                if(connectionSuccessful == null){
+                    connectionSuccessful = false;
+                }
                 //Log.w(TAG, "Wrote out to device: bytes = "+ count);
             } catch (IOException|NullPointerException e) { // STRICTLY to catch mmOutStream NPE
                 // Exception during write
diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/SdlRouterService.java b/sdl_android/src/main/java/com/smartdevicelink/transport/SdlRouterService.java
index f6a6a8736..e0f71a121 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/SdlRouterService.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/SdlRouterService.java
@@ -47,6 +47,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Set;
 import java.util.Vector;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
@@ -80,6 +81,7 @@ import android.content.pm.ResolveInfo;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.net.Uri;
+import android.os.BatteryManager;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.DeadObjectException;
@@ -92,6 +94,7 @@ import android.os.Parcel;
 import android.os.ParcelFileDescriptor;
 import android.os.Parcelable;
 import android.os.RemoteException;
+import android.support.annotation.NonNull;
 import android.util.Log;
 import android.util.SparseArray;
 import android.util.SparseIntArray;
@@ -136,7 +139,7 @@ public class SdlRouterService extends Service{
 	/**
 	 * <b> NOTE: DO NOT MODIFY THIS UNLESS YOU KNOW WHAT YOU'RE DOING.</b>
 	 */
-	protected static final int ROUTER_SERVICE_VERSION_NUMBER = 8;
+	protected static final int ROUTER_SERVICE_VERSION_NUMBER = 9;
 
 	private static final String ROUTER_SERVICE_PROCESS = "com.smartdevicelink.router";
 	
@@ -207,7 +210,7 @@ public class SdlRouterService extends Service{
 	private boolean startSequenceComplete = false;
 	
 	private ExecutorService packetExecutor = null;
-	HashMap<TransportType, PacketWriteTaskMaster>  packetWriteTaskMasterMap = null;
+	ConcurrentHashMap<TransportType, PacketWriteTaskMaster>  packetWriteTaskMasterMap = null;
 
 
 	/**
@@ -819,12 +822,14 @@ public class SdlRouterService extends Service{
 	    @SuppressWarnings("Convert2Diamond")
 		static class UsbTransferHandler extends Handler {
 	    	 final WeakReference<SdlRouterService> provider;
+	    	 Runnable usbCableDisconnectRunnable;
+	    	 BroadcastReceiver usbCableDisconnectBroadcastReceiver;
 
 	    	 public UsbTransferHandler(SdlRouterService provider){
 				 this.provider = new WeakReference<SdlRouterService>(provider);
 	    	 }
 
-	        @Override
+			@Override
 	        public void handleMessage(Message msg) {
 	        	if(this.provider.get() == null){
 	        		return;
@@ -832,14 +837,51 @@ public class SdlRouterService extends Service{
 	        	SdlRouterService service = this.provider.get();
 	        	switch(msg.what){
 					case TransportConstants.USB_CONNECTED_WITH_DEVICE:
+						service.enterForeground("Opening USB connection",FOREGROUND_TIMEOUT,false);
+						service.resetForegroundTimeOut(FOREGROUND_TIMEOUT);
         			int flags = msg.arg1;
-						ParcelFileDescriptor parcelFileDescriptor = (ParcelFileDescriptor)msg.obj;
-						if(parcelFileDescriptor != null){
-							//New USB constructor with PFD
-							service.usbTransport = new MultiplexUsbTransport(parcelFileDescriptor,service.usbHandler,msg.getData());
-							service.usbTransport.start();
 
+					ParcelFileDescriptor parcelFileDescriptor = (ParcelFileDescriptor)msg.obj;
+
+					if(parcelFileDescriptor != null) {
+						//New USB constructor with PFD
+						service.usbTransport = new MultiplexUsbTransport(parcelFileDescriptor, service.usbHandler, msg.getData());
+
+
+						usbCableDisconnectRunnable = new Runnable() {
+							@Override
+							public void run() {
+								if(provider.get() != null && AndroidTools.isUSBCableConnected(provider.get().getApplicationContext())) {
+									provider.get().usbTransport.start();
+								}
+							}
+						};
+						postDelayed(usbCableDisconnectRunnable, 4000);
+
+
+						// Register a BroadcastReceiver to stop USB transport if USB cable got disconnected
+						if (provider.get() != null) {
+							usbCableDisconnectBroadcastReceiver = new BroadcastReceiver() {
+								@Override
+								public void onReceive(Context context, Intent intent) {
+									int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1);
+									if (provider.get()!= null && plugged != BatteryManager.BATTERY_PLUGGED_AC && plugged != BatteryManager.BATTERY_PLUGGED_USB) {
+										try {
+											provider.get().getApplicationContext().unregisterReceiver(usbCableDisconnectBroadcastReceiver);
+										} catch (Exception e){ }
+										removeCallbacks(usbCableDisconnectRunnable);
+										if (provider.get().usbTransport != null) {
+											provider.get().usbTransport.stop();
+										}
+									}
+								}
+							};
+							provider.get().getApplicationContext().registerReceiver(usbCableDisconnectBroadcastReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
 						}
+
+
+					}
+
 	        		if(msg.replyTo!=null){
 	        			Message message = Message.obtain();
 	        			message.what = TransportConstants.ROUTER_USB_ACC_RECEIVED;
@@ -849,12 +891,7 @@ public class SdlRouterService extends Service{
 	        				e.printStackTrace();
 	        			}
 	        		}
-	        		if(service.isPrimaryTransportConnected() && ((TransportConstants.ROUTER_STATUS_FLAG_TRIGGER_PING  & flags) == TransportConstants.ROUTER_STATUS_FLAG_TRIGGER_PING)){
-	        			if(service.pingIntent == null){
-	        				service.initPingIntent();
-	        			}
-	        			AndroidTools.sendExplicitBroadcast(service.getApplicationContext(),service.pingIntent, null);
-	        		}
+
 	        		break;
 			        case TransportConstants.ALT_TRANSPORT_CONNECTED:
 			        	break;
@@ -1319,7 +1356,14 @@ public class SdlRouterService extends Service{
 				foregroundTimeoutRunnable = new Runnable() {
 					@Override
 					public void run() {
-						exitForeground();
+						if(!getConnectedTransports().isEmpty()){
+							// Updates notification to one of still connected transport
+							enterForeground(createConnectedNotificationText(),0,true);
+							return;
+						}else{
+							exitForeground();//Leave our foreground state as we don't have a connection
+
+						}
 					}
 				};
 			} else {
@@ -1392,7 +1436,8 @@ public class SdlRouterService extends Service{
 		PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);
 		builder.setContentIntent(pendingIntent);
 
-        if(chronometerLength > 0) {
+        if(chronometerLength > 0 && android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
+        	//The countdown method is only available in SDKs >= 24
         	builder.setWhen(chronometerLength + System.currentTimeMillis());
         	builder.setUsesChronometer(true);
         	builder.setChronometerCountDown(true);
@@ -1607,7 +1652,7 @@ public class SdlRouterService extends Service{
 		enterForeground(createConnectedNotificationText(),0,true);
 
 		if(packetWriteTaskMasterMap == null){
-			packetWriteTaskMasterMap = new HashMap<>();
+			packetWriteTaskMasterMap = new ConcurrentHashMap<>();
 		}
 
 		TransportType type = record.getType();
@@ -1615,6 +1660,7 @@ public class SdlRouterService extends Service{
 
 		if(packetWriteTaskMaster!=null){
 			packetWriteTaskMaster.close();
+			packetWriteTaskMaster.alert();
 		}
 		packetWriteTaskMaster = new PacketWriteTaskMaster();
 		packetWriteTaskMaster.setTransportType(type);
@@ -1670,6 +1716,9 @@ public class SdlRouterService extends Service{
 
 	public void onTransportDisconnected(TransportRecord record){
 		cachedModuleVersion = -1; //Reset our cached version
+		//Stop any current pings being sent before the proper state can be determined.
+		stopClientPings();
+
 		if(registeredApps != null && !registeredApps.isEmpty()){
 			Message message = Message.obtain();
 			message.what = TransportConstants.HARDWARE_CONNECTION_EVENT;
@@ -1686,7 +1735,61 @@ public class SdlRouterService extends Service{
 
 			message.setData(bundle);
 			notifyClients(message);
+
+			synchronized (REGISTERED_APPS_LOCK) {
+				Collection<RegisteredApp> apps = registeredApps.values();
+				for (RegisteredApp app : apps) {
+					app.unregisterTransport(-1,record.getType());
+
+				}
+			}
 		}
+		//Remove and close the packet task master assigned to this transport
+		if(packetWriteTaskMasterMap != null
+				&& record != null
+				&& packetWriteTaskMasterMap.containsKey(record.getType())){
+			PacketWriteTaskMaster master = packetWriteTaskMasterMap.remove(record.getType());
+			if(master != null){
+				master.close();
+				master.alert();
+			}
+		}
+		//Ensure the associated transport is dealt with
+		switch (record.getType()){
+			case BLUETOOTH:
+				synchronized(SESSION_LOCK){
+					if(bluetoothSessionMap!= null){
+						bluetoothSessionMap.clear();
+					}
+				}
+				if(!connectAsClient ){
+					if(!legacyModeEnabled && !closing){
+						initBluetoothSerialService();
+					}
+				}
+				break;
+			case USB:
+				if(usbTransport != null){
+					usbTransport = null;
+				}
+				synchronized(SESSION_LOCK){
+					if(usbSessionMap!= null){
+						usbSessionMap.clear();
+					}
+				}
+				break;
+			case TCP:
+				if(tcpTransport != null){
+					tcpTransport = null;
+				}
+				synchronized(SESSION_LOCK){
+					if(tcpSessionMap!=null){
+						tcpSessionMap.clear();
+					}
+				}
+				break;
+		}
+
 		if(!getConnectedTransports().isEmpty()){
 			// Updates notification to one of still connected transport
 			enterForeground(createConnectedNotificationText(),0,true);
@@ -1701,32 +1804,12 @@ public class SdlRouterService extends Service{
 		if(altTransportService!=null){  //If we still have an alt transport open, then we don't need to tell the clients to close
 			return;
 		}
-		switch (record.getType()){
-            case BLUETOOTH:
-                if(!connectAsClient ){
-                    if(!legacyModeEnabled && !closing){
-                        initBluetoothSerialService();
-                    }
-                }
-                break;
-            case USB:
-                break;
-            case TCP:
-                break;
-        }
-		Log.e(TAG, "Notifying client service of hardware disconnect.");
 
-		stopClientPings();
+		Log.e(TAG, "Notifying client service of hardware disconnect.");
 
 
-		PacketWriteTaskMaster packetWriteTaskMaster = packetWriteTaskMasterMap.remove(record.getType());
-		if(packetWriteTaskMaster!=null){
-			packetWriteTaskMaster.close();
-		}
-
 		//We've notified our clients, less clean up the mess now.
 		synchronized(SESSION_LOCK){
-			this.bluetoothSessionMap.clear();
 			this.sessionHashIdMap.clear();
 		}
 		synchronized(REGISTERED_APPS_LOCK){
@@ -2855,7 +2938,7 @@ public class SdlRouterService extends Service{
 		int priorityForBuffingMessage;
 		DeathRecipient deathNote = null;
 		//Packet queue vars
-		final HashMap<TransportType, PacketWriteTaskBlockingQueue> queues;
+		final ConcurrentHashMap<TransportType, PacketWriteTaskBlockingQueue> queues;
 		Handler queueWaitHandler;
 		Runnable queueWaitRunnable = null;
 		boolean queuePaused = false;
@@ -2873,7 +2956,7 @@ public class SdlRouterService extends Service{
 			this.appId = appId;
 			this.messenger = messenger;
 			this.sessionIds = new Vector<Long>();
-			this.queues = new HashMap<>();
+			this.queues = new ConcurrentHashMap<>();
 			queueWaitHandler = new Handler();
 			registeredTransports = new SparseArray<ArrayList<TransportType>>();
 			awaitingSession = new Vector<>();
@@ -2891,7 +2974,7 @@ public class SdlRouterService extends Service{
 			this.appId = appId;
 			this.messenger = messenger;
 			this.sessionIds = new Vector<Long>();
-			this.queues = new HashMap<>();
+			this.queues = new ConcurrentHashMap<>();
 			queueWaitHandler = new Handler();
 			registeredTransports = new SparseArray<ArrayList<TransportType>>();
 			awaitingSession = new Vector<>();
@@ -3049,14 +3132,25 @@ public class SdlRouterService extends Service{
 			}
 		}
 
-		protected boolean unregisterTransport(int sessionId, TransportType transportType){
+		protected boolean unregisterTransport(int sessionId, @NonNull TransportType transportType){
+			if(queues != null && queues.containsValue(transportType)){
+				PacketWriteTaskBlockingQueue queue = queues.remove(transportType);
+				queue.clear();
+			}
 			synchronized (TRANSPORT_LOCK){
-				if(this.registeredTransports.indexOfKey(sessionId) >= 0){
+				if(sessionId == -1){
+					int size = this.registeredTransports.size();
+					for(int i = 0; i <size; i++){
+						this.registeredTransports.valueAt(i).remove(transportType);
+					}
+					return true;
+				}else if(this.registeredTransports.indexOfKey(sessionId) >= 0){
 					return this.registeredTransports.get(sessionId).remove(transportType);
 				}else{
 					return false;
 				}
 			}
+
 		}
 
 		protected void unregisterAllTransports(int sessionId){
@@ -3066,7 +3160,7 @@ public class SdlRouterService extends Service{
 				}else if(sessionId == -1){
 					int size = this.registeredTransports.size();
 					for(int i = 0; i <size; i++){
-						this.registeredTransports.get(i).clear();
+						this.registeredTransports.valueAt(i).clear();
 					}
 				}
 			}
@@ -3347,6 +3441,7 @@ public class SdlRouterService extends Service{
 
 		public PacketWriteTaskMaster(){
 			this.setName("PacketWriteTaskMaster");
+			this.setDaemon(true);
 		}
 		protected void setTransportType(TransportType transportType){
 			this.transportType = transportType;
diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/TransportBroker.java b/sdl_android/src/main/java/com/smartdevicelink/transport/TransportBroker.java
index 21e9fedef..7bdd10857 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/TransportBroker.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/TransportBroker.java
@@ -118,6 +118,7 @@ public class TransportBroker {
                 Log.d(TAG, "Unbound from service " + className.getClassName());
                 routerServiceMessenger = null;
                 registeredWithRouterService = false;
+                unBindFromRouterService();
                 isBound = false;
                 onHardwareDisconnected(null, null);
             }
@@ -446,6 +447,7 @@ public class TransportBroker {
             routerServiceMessenger = null;
             queuedOnTransportConnect = null;
             unBindFromRouterService();
+            isBound = false;
         }
     }
 
@@ -464,12 +466,13 @@ public class TransportBroker {
         }
     }
 
-    private void unBindFromRouterService() {
+    private synchronized void unBindFromRouterService() {
         try {
-            if (getContext() != null && routerConnection != null) {
+            if (isBound && getContext() != null && routerConnection != null) {
                 getContext().unbindService(routerConnection);
+                isBound = false;
             } else {
-                Log.w(TAG, "Unable to unbind from router service, context was null");
+                Log.w(TAG, "Unable to unbind from router service. bound? " + isBound + " context? " + (getContext()!=null) + " router connection?" + (routerConnection != null));
             }
 
         } catch (IllegalArgumentException e) {
@@ -652,6 +655,10 @@ public class TransportBroker {
 
     @SuppressLint("InlinedApi")
     private boolean sendBindingIntent() {
+        if(this.isBound){
+            Log.e(TAG, "Already bound");
+            return false;
+        }
         if (this.routerPackage != null && this.routerClassName != null) {
             Log.d(TAG, "Sending bind request to " + this.routerPackage + " - " + this.routerClassName);
             Intent bindingIntent = new Intent();
diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/USBAccessoryAttachmentActivity.java b/sdl_android/src/main/java/com/smartdevicelink/transport/USBAccessoryAttachmentActivity.java
index 4b878c2aa..878715147 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/USBAccessoryAttachmentActivity.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/USBAccessoryAttachmentActivity.java
@@ -98,7 +98,6 @@ public class USBAccessoryAttachmentActivity extends Activity {
     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

-        checkUsbAccessoryIntent("Create");

     }

 

     @Override

@@ -107,7 +106,16 @@ public class USBAccessoryAttachmentActivity extends Activity {
         checkUsbAccessoryIntent("Resume");

     }

 

-    private void checkUsbAccessoryIntent(String sourceAction) {

+    @Override

+    protected void onNewIntent(Intent intent) {

+        super.onNewIntent(intent);

+        this.setIntent(intent);

+    }

+

+    private synchronized void checkUsbAccessoryIntent(String sourceAction) {

+        if(usbAccessory != null){

+            return;

+        }

         final Intent intent = getIntent();

         String action = intent.getAction();

         Log.d(TAG, sourceAction + " with action: " + action);

@@ -118,8 +126,16 @@ public class USBAccessoryAttachmentActivity extends Activity {
 

             wakeUpRouterService(getApplicationContext());

 

+        }else{

+            finish();

         }

+    }

 

+    @Override

+    protected void onDestroy() {

+        usbAccessory = null;

+        permissionGranted = null;

+        super.onDestroy();

     }

 

     @SuppressWarnings("deprecation")

diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/UsbTransferProvider.java b/sdl_android/src/main/java/com/smartdevicelink/transport/UsbTransferProvider.java
index 9657a2c27..1479fa9e1 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/UsbTransferProvider.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/UsbTransferProvider.java
@@ -40,6 +40,7 @@ import android.content.Intent;
 import android.content.ServiceConnection;
 import android.hardware.usb.UsbAccessory;
 import android.hardware.usb.UsbManager;
+import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
@@ -51,6 +52,8 @@ import android.os.RemoteException;
 import android.util.Log;
 
 import com.smartdevicelink.util.AndroidTools;
+
+import java.io.IOException;
 import java.lang.ref.WeakReference;
 
 @TargetApi(12)
@@ -103,12 +106,13 @@ public class UsbTransferProvider {
         if(context == null || service == null || usbAccessory == null){
             throw new IllegalStateException("Supplied params are not correct. Context == null? "+ (context==null) + " ComponentName == null? " + (service == null) + " Usb Accessory == null? " + usbAccessory);
         }
-        this.context = context;
-        this.routerService = service;
-        this.callback = callback;
-        this.clientMessenger = new Messenger(new ClientHandler(this));
-        usbPfd = getFileDescriptor(usbAccessory);
-        if(usbPfd != null){
+        usbPfd = getFileDescriptor(usbAccessory, context);
+        if(usbPfd != null && usbPfd.getFileDescriptor() != null && usbPfd.getFileDescriptor().valid()){
+            this.context = context;
+            this.routerService = service;
+            this.callback = callback;
+            this.clientMessenger = new Messenger(new ClientHandler(this));
+
             usbInfoBundle = new Bundle();
             usbInfoBundle.putString(MultiplexUsbTransport.MANUFACTURER, usbAccessory.getManufacturer());
             usbInfoBundle.putString(MultiplexUsbTransport.MODEL, usbAccessory.getModel());
@@ -117,20 +121,28 @@ public class UsbTransferProvider {
             usbInfoBundle.putString(MultiplexUsbTransport.SERIAL, usbAccessory.getSerial());
             usbInfoBundle.putString(MultiplexUsbTransport.DESCRIPTION, usbAccessory.getDescription());
             checkIsConnected();
+        }else{
+            Log.e(TAG, "Unable to open accessory");
+            clientMessenger = null;
+            if(callback != null){
+                callback.onUsbTransferUpdate(false);
+            }
         }
 
     }
 
     @SuppressLint("NewApi")
-    private ParcelFileDescriptor getFileDescriptor(UsbAccessory accessory) {
-        try {
-            UsbManager manager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
+    private ParcelFileDescriptor getFileDescriptor(UsbAccessory accessory, Context context) {
+        if (AndroidTools.isUSBCableConnected(context)) {
+            try {
+                UsbManager manager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
 
-            if (manager != null) {
-                return manager.openAccessory(accessory);
+                if (manager != null) {
+                    return manager.openAccessory(accessory);
+                }
+            } catch (Exception e) {
             }
-        }catch (Exception e){}
-
+        }
         return  null;
     }
 
@@ -181,11 +193,19 @@ public class UsbTransferProvider {
     }
 
     private void finish(){
-        if(callback != null){
-            callback.onUsbTransferUpdate(true);
+       try {
+            usbPfd.close();
+        } catch (IOException e) {
+            e.printStackTrace();
         }
+        usbPfd = null;
         unBindFromService();
         routerServiceMessenger =null;
+        context = null;
+        System.gc();
+        if(callback != null){
+            callback.onUsbTransferUpdate(true);
+        }
     }
 
     static class ClientHandler extends Handler {
diff --git a/sdl_android/src/main/java/com/smartdevicelink/util/AndroidTools.java b/sdl_android/src/main/java/com/smartdevicelink/util/AndroidTools.java
index 62f379031..4237845b7 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/util/AndroidTools.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/util/AndroidTools.java
@@ -35,11 +35,13 @@ package com.smartdevicelink.util;
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.content.pm.ResolveInfo;
 import android.content.pm.ServiceInfo;
+import android.os.BatteryManager;
 
 import com.smartdevicelink.transport.TransportConstants;
 
@@ -160,4 +162,15 @@ public class AndroidTools {
 		}
 	}
 
+	/**
+	 * Checks if the usb cable is physically connected or not
+	 * Note: the intent here is a sticky intent so registerReceiver is actually a synchronous call and doesn't register a receiver on each call
+	 * @param context a context instance
+	 * @return boolean value that represents whether the usb cable is physically connected or not
+	 */
+	public static boolean isUSBCableConnected(Context context) {
+		Intent intent = context.registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
+		int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1);
+		return plugged == BatteryManager.BATTERY_PLUGGED_AC || plugged == BatteryManager.BATTERY_PLUGGED_USB;
+	}
 }
diff --git a/sdl_android/src/main/res/values/sdl.xml b/sdl_android/src/main/res/values/sdl.xml
index ca8b15851..8ee8f70cb 100644
--- a/sdl_android/src/main/res/values/sdl.xml
+++ b/sdl_android/src/main/res/values/sdl.xml
@@ -2,7 +2,7 @@
 <resources>
     <string name="sdl_router_service_version_name" translatable="false">sdl_router_version</string>
 
-    <integer name="sdl_router_service_version_value">8</integer>
+    <integer name="sdl_router_service_version_value">9</integer>
 
     <string name="sdl_router_service_is_custom_name" translatable="false">sdl_custom_router</string>
 </resources>