Make linter happy: add final

src/org/kde/kdeconnect/Backends/BluetoothBackend/BluetoothLinkProvider.java

@@ -43,7 +43,7 @@ public class BluetoothLinkProvider extends BaseLinkProvider {
     private final Map<String, BluetoothLink> visibleComputers = new HashMap<>();
     private final Map<BluetoothDevice, BluetoothSocket> sockets = new HashMap<>();
 
-    private BluetoothAdapter bluetoothAdapter;
+    private final BluetoothAdapter bluetoothAdapter;
 
     private ServerRunnable serverRunnable;
     private ClientRunnable clientRunnable;

src/org/kde/kdeconnect/Backends/BluetoothBackend/ConnectionMultiplexer.java

@@ -19,7 +19,7 @@ public final class ConnectionMultiplexer implements Closeable {
     private static final int BUFFER_SIZE = 4096;
 
     private static final class ChannelInputStream extends InputStream implements Closeable {
-        Channel channel;
+        final Channel channel;
 
         ChannelInputStream(Channel channel) {
             this.channel = channel;
@@ -57,7 +57,7 @@ public final class ConnectionMultiplexer implements Closeable {
     }
 
     private static final class ChannelOutputStream extends OutputStream implements Closeable {
-        Channel channel;
+        final Channel channel;
 
         ChannelOutputStream(Channel channel) {
             this.channel = channel;
@@ -92,9 +92,9 @@ public final class ConnectionMultiplexer implements Closeable {
     }
 
     private static final class Channel implements Closeable {
-        ConnectionMultiplexer multiplexer;
+        final ConnectionMultiplexer multiplexer;
-        UUID id;
+        final UUID id;
-        ByteBuffer read_buffer = ByteBuffer.allocate(BUFFER_SIZE);
+        final ByteBuffer read_buffer = ByteBuffer.allocate(BUFFER_SIZE);
         final Object lock = new Object();
         boolean open = true;
         int requestedReadAmount = 0; //Number of times we requested some bytes from the channel
@@ -199,7 +199,7 @@ public final class ConnectionMultiplexer implements Closeable {
     }
 
     private BluetoothSocket socket;
-    private Map<UUID, Channel> channels = new HashMap<>();
+    private final Map<UUID, Channel> channels = new HashMap<>();
     private final Object lock = new Object();
     private boolean open = true;
     private boolean receivedProtocolVersion = false;

src/org/kde/kdeconnect/DevicePacketQueue.java

@@ -17,7 +17,7 @@ class DevicePacketQueue {
         /**
          * Replacement ID: if positive, it can be replaced by later packets with the same ID
          */
-        int replaceID;
+        final int replaceID;
         Device.SendPacketStatusCallback callback;
 
         Item(NetworkPacket packet, int replaceID, Device.SendPacketStatusCallback callback) {
@@ -28,7 +28,7 @@ class DevicePacketQueue {
     }
 
     private final ArrayDeque<Item> items = new ArrayDeque<>();
-    private Device mDevice;
+    private final Device mDevice;
     private final Object lock = new Object();
     private boolean exit = false;
 

src/org/kde/kdeconnect/Helpers/TelephonyHelper.java

@@ -360,7 +360,7 @@ public class TelephonyHelper {
         private int mmsProxyPort = 80; // Default port should be 80 according to code comment in Android's ApnSettings.java
 
         public static class Builder {
-            private org.kde.kdeconnect.Helpers.TelephonyHelper.ApnSetting internalApnSetting;
+            private final org.kde.kdeconnect.Helpers.TelephonyHelper.ApnSetting internalApnSetting;
 
             public Builder() {
                 internalApnSetting = new ApnSetting();

src/org/kde/kdeconnect/NetworkPacket.java

@@ -310,9 +310,9 @@ public class NetworkPacket {
     }
 
     public static class Payload {
-        private InputStream inputStream;
+        private final InputStream inputStream;
-        private Socket inputSocket;
+        private final Socket inputSocket;
-        private long payloadSize;
+        private final long payloadSize;
 
         public Payload(long payloadSize) {
             this((InputStream)null, payloadSize);

src/org/kde/kdeconnect/Plugins/MousePadPlugin/MousePadGestureDetector.java

@@ -13,7 +13,7 @@ import android.view.ViewConfiguration;
 class MousePadGestureDetector {
 
     private static final int TAP_TIMEOUT = ViewConfiguration.getTapTimeout() + 100;
-    private OnGestureListener mGestureListener;
+    private final OnGestureListener mGestureListener;
 
     private long mFirstDownTime = 0;
 

src/org/kde/kdeconnect/Plugins/NotificationsPlugin/AppDatabase.java

@@ -43,9 +43,9 @@ class AppDatabase {
             + KEY_PRIVACY_OPTIONS + " INTEGER NOT NULL); ";
 
 
-    private SQLiteDatabase ourDatabase;
+    private final SQLiteDatabase ourDatabase;
-    private DbHelper ourHelper;
+    private final DbHelper ourHelper;
-    private SharedPreferences prefs;
+    private final SharedPreferences prefs;
 
     AppDatabase(Context context, boolean readonly) {
         ourHelper = new DbHelper(context);

src/org/kde/kdeconnect/Plugins/SftpPlugin/SftpPlugin.java

@@ -36,7 +36,7 @@ public class SftpPlugin extends Plugin implements SharedPreferences.OnSharedPref
     private final static String PACKET_TYPE_SFTP = "kdeconnect.sftp";
     private final static String PACKET_TYPE_SFTP_REQUEST = "kdeconnect.sftp.request";
 
-    static int PREFERENCE_KEY_STORAGE_INFO_LIST = R.string.sftp_preference_key_storage_info_list;
+    static final int PREFERENCE_KEY_STORAGE_INFO_LIST = R.string.sftp_preference_key_storage_info_list;
 
     private static final SimpleSftpServer server = new SimpleSftpServer();
 
@@ -242,8 +242,10 @@ public class SftpPlugin extends Plugin implements SharedPreferences.OnSharedPref
         private static final String KEY_DISPLAY_NAME = "DisplayName";
         private static final String KEY_URI = "Uri";
 
-        @NonNull String displayName;
+        @NonNull
-        @NonNull Uri uri;
+        String displayName;
+        @NonNull
+        final Uri uri;
 
         StorageInfo(@NonNull String displayName, @NonNull Uri uri) {
             this.displayName = displayName;

src/org/kde/kdeconnect/Plugins/SharePlugin/CompositeUploadFileJob.java

@@ -41,13 +41,13 @@ import java.util.List;
  */
 public class CompositeUploadFileJob extends BackgroundJob<Device, Void> {
     private boolean isRunning;
-    private Handler handler;
+    private final Handler handler;
     private String currentFileName;
     private int currentFileNum;
     private boolean updatePacketPending;
     private long totalSend;
     private int prevProgressPercentage;
-    private UploadNotification uploadNotification;
+    private final UploadNotification uploadNotification;
 
     private final Object lock;                              //Use to protect concurrent access to the variables below
     @GuardedBy("lock")

src/org/kde/kdeconnect/Plugins/SharePlugin/ReceiveNotification.java

@@ -34,7 +34,7 @@ class ReceiveNotification {
     private final int notificationId;
     private NotificationCompat.Builder builder;
     private final Device device;
-    private long jobId;
+    private final long jobId;
 
     //https://documentation.onesignal.com/docs/android-customizations#section-big-picture
     private static final int bigImageWidth = 1440;

src/org/kde/kdeconnect/Plugins/SharePlugin/UploadNotification.java

@@ -25,7 +25,7 @@ class UploadNotification {
     private NotificationCompat.Builder builder;
     private final int notificationId;
     private final Device device;
-    private long jobId;
+    private final long jobId;
 
     UploadNotification(Device device, long jobId) {
         this.device = device;

src/org/kde/kdeconnect/Plugins/SystemVolumePlugin/Sink.java

@@ -21,10 +21,10 @@ class Sink {
     }
 
     private int volume;
-    private String description;
+    private final String description;
-    private String name;
+    private final String name;
     private boolean mute;
-    private int maxVolume;
+    private final int maxVolume;
     private boolean enabled;
 
     private final List<UpdateListener> listeners;

src/org/kde/kdeconnect/UserInterface/AlertDialogFragment.java

@@ -118,7 +118,7 @@ public class AlertDialogFragment extends DialogFragment implements DialogInterfa
     }
 
     public static abstract class AbstractBuilder<B extends AbstractBuilder<B, F>, F extends DialogFragment> {
-        Bundle args;
+        final Bundle args;
 
         AbstractBuilder() {
             args = new Bundle();

src/org/kde/kdeconnect/UserInterface/CustomDevicesAdapter.java

@@ -88,7 +88,7 @@ public class CustomDevicesAdapter extends RecyclerView.Adapter<CustomDevicesAdap
     }
 
     private static class ItemTouchHelperCallback extends ItemTouchHelper.Callback {
-        @NonNull private Callback callback;
+        @NonNull private final Callback callback;
 
         private ItemTouchHelperCallback(@NonNull Callback callback) {
             this.callback = callback;

src/org/kde/kdeconnect/async/BackgroundJob.java

@@ -11,13 +11,13 @@ import androidx.annotation.NonNull;
 import java.util.concurrent.atomic.AtomicLong;
 
 public abstract class BackgroundJob<I, R> implements Runnable {
-    private static AtomicLong atomicLong = new AtomicLong(0);
+    private static final AtomicLong atomicLong = new AtomicLong(0);
     protected volatile boolean canceled;
     private BackgroundJobHandler backgroundJobHandler;
-    private long id;
+    private final long id;
 
-    protected I requestInfo;
+    protected final I requestInfo;
-    private Callback<R> callback;
+    private final Callback<R> callback;
 
     public BackgroundJob(I requestInfo, Callback<R> callback) {
         this.id = atomicLong.incrementAndGet();