Some more lint warnings fixed

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/AbstractFragmentPagerAdapter.java

@@ -8,7 +8,7 @@ import java.util.HashSet;
 import java.util.Set;
 
 public abstract class AbstractFragmentPagerAdapter extends FragmentStatePagerAdapter {
-    private Set<AbstractGBFragment> fragments = new HashSet<>();
+    private final Set<AbstractGBFragment> fragments = new HashSet<>();
     private Object primaryFragment;
 
     public AbstractFragmentPagerAdapter(FragmentManager fm) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/AbstractSettingsActivity.java

@@ -56,7 +56,7 @@ public abstract class AbstractSettingsActivity extends PreferenceActivity {
     }
 
     private static class ExtraSetSummaryOnChangeListener extends SimpleSetSummaryOnChangeListener {
-        private Preference.OnPreferenceChangeListener delegate;
+        private final Preference.OnPreferenceChangeListener delegate;
 
         public ExtraSetSummaryOnChangeListener(Preference.OnPreferenceChangeListener delegate) {
             this.delegate = delegate;
@@ -72,7 +72,7 @@ public abstract class AbstractSettingsActivity extends PreferenceActivity {
         }
     }
 
-    private static SimpleSetSummaryOnChangeListener sBindPreferenceSummaryToValueListener = new SimpleSetSummaryOnChangeListener();
+    private static final SimpleSetSummaryOnChangeListener sBindPreferenceSummaryToValueListener = new SimpleSetSummaryOnChangeListener();
 
     @Override
     protected void onPostCreate(Bundle savedInstanceState) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/AppBlacklistActivity.java

@@ -35,7 +35,7 @@ import nodomain.freeyourgadget.gadgetbridge.R;
 public class AppBlacklistActivity extends Activity {
     private static final Logger LOG = LoggerFactory.getLogger(AppBlacklistActivity.class);
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/AppManagerActivity.java

@@ -37,7 +37,7 @@ public class AppManagerActivity extends Activity {
             = "nodomain.freeyourgadget.gadgetbridge.appmanager.action.refresh_applist";
     private static final Logger LOG = LoggerFactory.getLogger(AppManagerActivity.class);
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/DebugActivity.java

@@ -50,7 +50,7 @@ public class DebugActivity extends Activity {
     private Button importDBButton;
     private EditText editContent;
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             if (intent.getAction().equals(ControlCenter.ACTION_QUIT)) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/DiscoveryActivity.java

@@ -36,9 +36,9 @@ public class DiscoveryActivity extends Activity implements AdapterView.OnItemCli
     private static final Logger LOG = LoggerFactory.getLogger(DiscoveryActivity.class);
     private static final long SCAN_DURATION = 60000; // 60s
 
-    private Handler handler = new Handler();
+    private final Handler handler = new Handler();
 
-    private BroadcastReceiver bluetoothReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver bluetoothReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             switch (intent.getAction()) {
@@ -78,14 +78,14 @@ public class DiscoveryActivity extends Activity implements AdapterView.OnItemCli
         }
     };
 
-    private BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
+    private final BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
         @Override
         public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
             handleDeviceFound(device, (short) rssi);
         }
     };
 
-    private Runnable stopRunnable = new Runnable() {
+    private final Runnable stopRunnable = new Runnable() {
         @Override
         public void run() {
             stopDiscovery();
@@ -94,7 +94,7 @@ public class DiscoveryActivity extends Activity implements AdapterView.OnItemCli
 
     private ProgressBar progressView;
     private BluetoothAdapter adapter;
-    private ArrayList<GBDeviceCandidate> deviceCandidates = new ArrayList<>();
+    private final ArrayList<GBDeviceCandidate> deviceCandidates = new ArrayList<>();
     private DeviceCandidateAdapter cadidateListAdapter;
     private Button startButton;
     private Scanning isScanning = Scanning.SCANNING_OFF;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/FwAppInstallerActivity.java

@@ -45,7 +45,7 @@ public class FwAppInstallerActivity extends Activity implements InstallActivity
     private InstallHandler installHandler;
     private boolean mayConnect;
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();
@@ -72,7 +72,7 @@ public class FwAppInstallerActivity extends Activity implements InstallActivity
     };
     private ProgressBar mProgressBar;
     private ListView itemListView;
-    private List<ItemWithDetails> mItems = new ArrayList<>();
+    private final List<ItemWithDetails> mItems = new ArrayList<>();
     private ItemWithDetailsAdapter mItemAdapter;
 
     private void refreshBusyState(GBDevice dev) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/AbstractChartFragment.java

@@ -60,12 +60,12 @@ import nodomain.freeyourgadget.gadgetbridge.util.DeviceHelper;
  * shift the date by one day.
  */
 public abstract class AbstractChartFragment extends AbstractGBFragment {
-    protected int ANIM_TIME = 350;
+    protected final int ANIM_TIME = 350;
 
     private static final Logger LOG = LoggerFactory.getLogger(AbstractChartFragment.class);
 
     private final Set<String> mIntentFilterActions;
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             AbstractChartFragment.this.onReceive(context, intent);
@@ -82,7 +82,7 @@ public abstract class AbstractChartFragment extends AbstractGBFragment {
     protected static final class ActivityConfig {
         public final int type;
         public final String label;
-        public Integer color;
+        public final Integer color;
 
         public ActivityConfig(int kind, String label, Integer color) {
             this.type = kind;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/ChartsActivity.java

@@ -80,7 +80,7 @@ public class ChartsActivity extends AbstractGBFragmentActivity implements Charts
         }
     }
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/LiveActivityFragment.java

@@ -60,7 +60,7 @@ public class LiveActivityFragment extends AbstractChartFragment {
     private CustomBarChart mStepsPerMinuteCurrentChart;
     private CustomBarChart mTotalStepsChart;
 
-    private Steps mSteps = new Steps();
+    private final Steps mSteps = new Steps();
     private ScheduledExecutorService pulseScheduler;
     private int maxStepsResetCounter;
 
@@ -140,7 +140,7 @@ public class LiveActivityFragment extends AbstractChartFragment {
         }
     }
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/MiBandPairingActivity.java

@@ -26,7 +26,7 @@ public class MiBandPairingActivity extends Activity {
     private TextView message;
     private boolean isPairing;
     private String macAddress;
-    private BroadcastReceiver mPairingReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mPairingReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             if (GBDevice.ACTION_DEVICE_CHANGED.equals(intent.getAction())) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/MiBandSampleProvider.java

@@ -20,7 +20,7 @@ public class MiBandSampleProvider implements SampleProvider {
 //    public static final byte TYPE_WALKING = 1;
 
     // maybe this should be configurable 256 seems way off, though.
-    private float movementDivisor = 180.0f; //256.0f;
+    private final float movementDivisor = 180.0f; //256.0f;
 
     @Override
     public int normalizeType(byte rawType) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/MiBandService.java

@@ -207,7 +207,7 @@ public class MiBandService {
 
 	*/
 
-    private static Map<UUID, String> MIBAND_DEBUG;
+    private static final Map<UUID, String> MIBAND_DEBUG;
 
     static {
         MIBAND_DEBUG = new HashMap<>();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/UserInfo.java

@@ -10,13 +10,13 @@ import java.util.Arrays;
  */
 public class UserInfo {
 
-    private String btAddress;
+    private final String btAddress;
-    private String alias;
+    private final String alias;
-    private int gender;
+    private final int gender;
-    private int age;
+    private final int age;
-    private int height;
+    private final int height;
-    private int weight;
+    private final int weight;
-    private int type;
+    private final int type;
 
     private byte[] data = new byte[20];
 

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/VibrationProfile.java

@@ -40,8 +40,8 @@ public class VibrationProfile {
 
     private final String id;
 
-    private int[] onOffSequence;
+    private final int[] onOffSequence;
-    private short repeat;
+    private final short repeat;
 
     /**
      * Creates a new profile instance.

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/MisfitSampleProvider.java

@@ -4,7 +4,7 @@ import nodomain.freeyourgadget.gadgetbridge.devices.SampleProvider;
 
 public class MisfitSampleProvider implements SampleProvider {
 
-    protected float movementDivisor = 300f;
+    protected final float movementDivisor = 300f;
 
     @Override
     public int normalizeType(byte rawType) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/STM32CRC.java

@@ -14,7 +14,7 @@ import java.nio.ByteOrder;
 public class STM32CRC {
     private int crc;
     private byte rem;
-    private byte buffer[] = {0, 0, 0, 0};
+    private final byte[] buffer = {0, 0, 0, 0};
 
     private static final int[] crc_table = {
             0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/NotificationListener.java

@@ -1,7 +1,6 @@
 package nodomain.freeyourgadget.gadgetbridge.externalevents;
 
 import android.annotation.SuppressLint;
-import android.annotation.TargetApi;
 import android.app.ActivityManager;
 import android.app.Notification;
 import android.app.PendingIntent;
@@ -12,7 +11,6 @@ import android.content.IntentFilter;
 import android.content.SharedPreferences;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
-import android.os.Build;
 import android.os.Bundle;
 import android.os.PowerManager;
 import android.preference.PreferenceManager;
@@ -41,7 +39,7 @@ public class NotificationListener extends NotificationListenerService {
     public static final String ACTION_MUTE
             = "nodomain.freeyourgadget.gadgetbridge.notificationlistener.action.mute";
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @SuppressLint("NewApi")
         @Override
         public void onReceive(Context context, Intent intent) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/impl/GBAlarm.java

@@ -18,7 +18,7 @@ import static nodomain.freeyourgadget.gadgetbridge.devices.miband.MiBandConst.PR
 
 public class GBAlarm implements Alarm {
 
-    private int index;
+    private final int index;
     private boolean enabled;
     private boolean smartWakeup;
     private int repetition;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/impl/GBDeviceCandidate.java

@@ -14,8 +14,8 @@ import nodomain.freeyourgadget.gadgetbridge.model.DeviceType;
  * support this candidate, will the candidate be promoted to a GBDevice.
  */
 public class GBDeviceCandidate implements Parcelable {
-    private BluetoothDevice device;
+    private final BluetoothDevice device;
-    private short rssi;
+    private final short rssi;
     private DeviceType deviceType = DeviceType.UNKNOWN;
 
     public GBDeviceCandidate(BluetoothDevice device, short rssi) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/model/ActivityAmount.java

@@ -5,7 +5,7 @@ import android.content.Context;
 import nodomain.freeyourgadget.gadgetbridge.R;
 
 public class ActivityAmount {
-    private int activityKind;
+    private final int activityKind;
     private short percent;
     private long totalSeconds;
 

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/model/ActivityAmounts.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 public class ActivityAmounts {
-    private List<ActivityAmount> amounts = new ArrayList<>(4);
+    private final List<ActivityAmount> amounts = new ArrayList<>(4);
     private long totalSeconds;
 
     public void addAmount(ActivityAmount amount) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceCommunicationService.java

@@ -93,7 +93,7 @@ public class DeviceCommunicationService extends Service {
     private MusicPlaybackReceiver mMusicPlaybackReceiver = null;
     private TimeChangeReceiver mTimeChangeReceiver = null;
 
-    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceSupportFactory.java

@@ -18,7 +18,7 @@ import nodomain.freeyourgadget.gadgetbridge.util.GB;
 
 public class DeviceSupportFactory {
     private final BluetoothAdapter mBtAdapter;
-    private Context mContext;
+    private final Context mContext;
 
     public DeviceSupportFactory(Context context) {
         mContext = context;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/AbstractBTLEDeviceSupport.java

@@ -33,7 +33,7 @@ public abstract class AbstractBTLEDeviceSupport extends AbstractDeviceSupport im
 
     private BtLEQueue mQueue;
     private HashMap<UUID, BluetoothGattCharacteristic> mAvailableCharacteristics;
-    private Set<UUID> mSupportedServices = new HashSet<>(4);
+    private final Set<UUID> mSupportedServices = new HashSet<>(4);
 
     public static final String BASE_UUID = "0000%s-0000-1000-8000-00805f9b34fb"; //this is common for all BTLE devices. see http://stackoverflow.com/questions/18699251/finding-out-android-bluetooth-le-gatt-profiles
 

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/BtLEQueue.java

@@ -31,8 +31,8 @@ public final class BtLEQueue {
     private static final Logger LOG = LoggerFactory.getLogger(BtLEQueue.class);
 
     private final Object mGattMonitor = new Object();
-    private GBDevice mGbDevice;
+    private final GBDevice mGbDevice;
-    private BluetoothAdapter mBluetoothAdapter;
+    private final BluetoothAdapter mBluetoothAdapter;
     private BluetoothGatt mBluetoothGatt;
     /**
      * When an automatic reconnect was attempted after a connection breakdown (error)
@@ -41,12 +41,12 @@ public final class BtLEQueue {
 
     private static final long MIN_MILLIS_BEFORE_RECONNECT = 1000 * 60 * 5; // 5 minutes
 
-    private volatile BlockingQueue<Transaction> mTransactions = new LinkedBlockingQueue<>();
+    private final BlockingQueue<Transaction> mTransactions = new LinkedBlockingQueue<>();
     private volatile boolean mDisposed;
     private volatile boolean mCrashed;
     private volatile boolean mAbortTransaction;
 
-    private Context mContext;
+    private final Context mContext;
     private CountDownLatch mWaitForActionResultLatch;
     private CountDownLatch mConnectionLatch;
     private BluetoothGattCharacteristic mWaitCharacteristic;
@@ -284,7 +284,7 @@ public final class BtLEQueue {
         private
         @Nullable
         GattCallback mTransactionGattCallback;
-        private GattCallback mExternalGattCallback;
+        private final GattCallback mExternalGattCallback;
 
         public InternalGattCallback(GattCallback externalGattCallback) {
             mExternalGattCallback = externalGattCallback;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/GattCharacteristic.java

@@ -178,7 +178,7 @@ public class GattCharacteristic {
 
     //do we need this?
 
-    private static Map<UUID, String> GATTCHARACTERISTIC_DEBUG;
+    private static final Map<UUID, String> GATTCHARACTERISTIC_DEBUG;
 
     static {
         GATTCHARACTERISTIC_DEBUG = new HashMap<>();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/GattService.java

@@ -43,7 +43,7 @@ public class GattService {
 
     //do we need this?
 
-    private static Map<UUID, String> GATTSERVICE_DEBUG;
+    private static final Map<UUID, String> GATTSERVICE_DEBUG;
 
     static {
         GATTSERVICE_DEBUG = new HashMap<>();

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/Transaction.java

@@ -16,9 +16,9 @@ import java.util.Locale;
  * @author TREND
  */
 public class Transaction {
-    private String mName;
+    private final String mName;
-    private List<BtLEAction> mActions = new ArrayList<>(4);
+    private final List<BtLEAction> mActions = new ArrayList<>(4);
-    private long creationTimestamp = System.currentTimeMillis();
+    private final long creationTimestamp = System.currentTimeMillis();
     private
     @Nullable
     GattCallback gattCallback;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/TransactionBuilder.java

@@ -14,7 +14,7 @@ import nodomain.freeyourgadget.gadgetbridge.service.btle.actions.WriteAction;
 public class TransactionBuilder {
     private static final Logger LOG = LoggerFactory.getLogger(TransactionBuilder.class);
 
-    private Transaction mTransaction;
+    private final Transaction mTransaction;
     private boolean mQueued;
 
     public TransactionBuilder(String taskName) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/SetProgressAction.java

@@ -7,9 +7,9 @@ import nodomain.freeyourgadget.gadgetbridge.util.GB;
 
 public class SetProgressAction extends PlainAction {
 
-    private String text;
+    private final String text;
-    private boolean ongoing;
+    private final boolean ongoing;
-    private int percentage;
+    private final int percentage;
     private final Context context;
 
     /**

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/WaitAction.java

@@ -4,7 +4,7 @@ import android.bluetooth.BluetoothGatt;
 
 public class WaitAction extends PlainAction {
 
-    private int mMillis;
+    private final int mMillis;
 
     public WaitAction(int millis) {
         mMillis = millis;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/WriteAction.java

@@ -13,7 +13,7 @@ import nodomain.freeyourgadget.gadgetbridge.service.btle.BtLEAction;
  */
 public class WriteAction extends BtLEAction {
 
-    private byte[] value;
+    private final byte[] value;
 
     public WriteAction(BluetoothGattCharacteristic characteristic, byte[] value) {
         super(characteristic);

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/miband/AbstractInfo.java

@@ -1,7 +1,7 @@
 package nodomain.freeyourgadget.gadgetbridge.service.devices.miband;
 
 public class AbstractInfo {
-    protected byte[] mData;
+    protected final byte[] mData;
 
     public AbstractInfo(byte[] data) {
         mData = new byte[data.length];

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/miband/MiBandSupport.java

@@ -78,8 +78,8 @@ public class MiBandSupport extends AbstractBTLEDeviceSupport {
 
     private DeviceInfo mDeviceInfo;
 
-    GBDeviceEventVersionInfo versionCmd = new GBDeviceEventVersionInfo();
+    private final GBDeviceEventVersionInfo versionCmd = new GBDeviceEventVersionInfo();
-    GBDeviceEventBatteryInfo batteryCmd = new GBDeviceEventBatteryInfo();
+    private final GBDeviceEventBatteryInfo batteryCmd = new GBDeviceEventBatteryInfo();
 
     public MiBandSupport() {
         addSupportedService(GattService.UUID_SERVICE_GENERIC_ACCESS);

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/miband/operations/FetchActivityOperation.java

@@ -50,13 +50,13 @@ public class FetchActivityOperation extends AbstractBTLEOperation<MiBandSupport>
     //private ScheduledExecutorService scheduleTaskExecutor;
     //private ScheduledFuture scheduledTask;
 
-    private int activityMetadataLength = 11;
+    private final int activityMetadataLength = 11;
 
     //temporary buffer, size is a multiple of 60 because we want to store complete minutes (1 minute = 3 bytes)
     private static final int activityDataHolderSize = 3 * 60 * 4; // 4h
 
     private static class ActivityStruct {
-        private byte[] activityDataHolder = new byte[activityDataHolderSize];
+        private final byte[] activityDataHolder = new byte[activityDataHolderSize];
         //index of the buffer above
         private int activityDataHolderProgress = 0;
         //number of bytes we will get in a single data transfer, used as counter

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleIoThread.java

@@ -56,7 +56,7 @@ public class PebbleIoThread extends GBDeviceIoThread {
     public static final String PEBBLEKIT_ACTION_APP_START = "com.getpebble.action.app.START";
     public static final String PEBBLEKIT_ACTION_APP_STOP = "com.getpebble.action.app.STOP";
 
-    SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(getContext());
+    final SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(getContext());
 
     private final PebbleProtocol mPebbleProtocol;
     private final PebbleSupport mPebbleSupport;
@@ -419,6 +419,7 @@ public class PebbleIoThread extends GBDeviceIoThread {
                 mOutStream.flush();
             }
         } catch (IOException e) {
+            LOG.error("Error writing.", e);
         }
     }
 

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleProtocol.java

@@ -228,7 +228,7 @@ public class PebbleProtocol extends GBDeviceProtocol {
             "snowy_evt2", "snowy_dvt", "spalding_dvt", "snowy_s3", "spalding"
     };
 
-    private static Random mRandom = new Random();
+    private static final Random mRandom = new Random();
 
     boolean isFw3x = false;
     boolean mForceProtocol = false;
@@ -327,14 +327,14 @@ public class PebbleProtocol extends GBDeviceProtocol {
 
 
     byte last_id = -1;
-    private ArrayList<UUID> tmpUUIDS = new ArrayList<>();
+    private final ArrayList<UUID> tmpUUIDS = new ArrayList<>();
 
     private static final UUID UUID_GBPEBBLE = UUID.fromString("61476764-7465-7262-6469-656775527a6c");
     private static final UUID UUID_MORPHEUZ = UUID.fromString("5be44f1d-d262-4ea6-aa30-ddbec1e3cab2");
     private static final UUID UUID_WHETHERNEAT = UUID.fromString("3684003b-a685-45f9-a713-abc6364ba051");
     private static final UUID UUID_MISFIT = UUID.fromString("0b73b76a-cd65-4dc2-9585-aaa213320858");
 
-    private static Map<UUID, AppMessageHandler> mAppMessageHandlers = new HashMap<>();
+    private static final Map<UUID, AppMessageHandler> mAppMessageHandlers = new HashMap<>();
 
     {
         mAppMessageHandlers.put(UUID_GBPEBBLE, new AppMessageHandlerGBPebble(UUID_GBPEBBLE, PebbleProtocol.this));

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/DeviceHelper.java

@@ -13,7 +13,7 @@ import nodomain.freeyourgadget.gadgetbridge.impl.GBDevice;
 import nodomain.freeyourgadget.gadgetbridge.impl.GBDeviceCandidate;
 
 public class DeviceHelper {
-    private static DeviceHelper instance = new DeviceHelper();
+    private static final DeviceHelper instance = new DeviceHelper();
 
     public static DeviceHelper getInstance() {
         return instance;

app/src/test/java/nodomain/freeyourgadget/gadgetbridge/service/AbstractServiceTestCase.java

@@ -19,7 +19,7 @@ import nodomain.freeyourgadget.gadgetbridge.test.MockHelper;
 
 public abstract class AbstractServiceTestCase<T extends Service> {
     private static final int ID = -1; // currently not supported
-    private Class<T> mServiceClass;
+    private final Class<T> mServiceClass;
     private T mServiceInstance;
     private Context mContext;
     private Application mApplication;

app/src/test/java/nodomain/freeyourgadget/gadgetbridge/test/GBMockIntent.java

@@ -12,7 +12,7 @@ import java.util.Map;
 
 public class GBMockIntent extends Intent {
     private String mAction;
-    private Map<String,Object> extras = new HashMap<>();
+    private final Map<String,Object> extras = new HashMap<>();
 
     @NonNull
     @Override