Lint fixes

app/src/main/java/ch/dissem/apps/abit/AbstractItemListFragment.java

@@ -37,7 +37,7 @@ public abstract class AbstractItemListFragment<T> extends ListFragment implement
      * A dummy implementation of the {@link ListSelectionListener} interface that does
      * nothing. Used only when this fragment is not attached to an activity.
      */
-    private static ListSelectionListener<Object> dummyCallbacks = plaintext -> {
+    private static final ListSelectionListener<Object> dummyCallbacks = plaintext -> {
     };
     /**
      * The fragment's current callback object, which is notified of list item

app/src/main/java/ch/dissem/apps/abit/AddressListFragment.java

@@ -144,11 +144,6 @@ public class AddressListFragment extends AbstractItemListFragment<BitmessageAddr
         return view;
     }
 
-    @Override
-    public void startActivityForResult(Intent intent, int requestCode) {
-        super.startActivityForResult(intent, requestCode);
-    }
-
     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
         if (data != null && data.hasExtra("SCAN_RESULT")) {

app/src/main/java/ch/dissem/apps/abit/CreateAddressActivity.java

@@ -20,7 +20,6 @@ import android.app.Activity;
 import android.net.Uri;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
-import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.Switch;
@@ -61,17 +60,12 @@ public class CreateAddressActivity extends AppCompatActivity {
         }
 
         final Button cancel = (Button) findViewById(R.id.cancel);
-        cancel.setOnClickListener(new View.OnClickListener() {
+        cancel.setOnClickListener(v -> {
-            @Override
-            public void onClick(View v) {
             setResult(Activity.RESULT_CANCELED);
             finish();
-            }
         });
         final Button ok = (Button) findViewById(R.id.do_import);
-        ok.setOnClickListener(new View.OnClickListener() {
+        ok.setOnClickListener(v -> {
-            @Override
-            public void onClick(View v) {
             String addressText = String.valueOf(address.getText()).trim();
             try {
                 BitmessageAddress bmAddress = new BitmessageAddress(addressText);
@@ -89,7 +83,6 @@ public class CreateAddressActivity extends AppCompatActivity {
             } catch (RuntimeException e) {
                 address.setError(getString(R.string.error_illegal_address));
             }
-            }
         });
     }
 

app/src/main/java/ch/dissem/apps/abit/DetailActivity.java

@@ -12,7 +12,7 @@ import com.mikepenz.materialize.MaterializeBuilder;
 /**
  * @author Christian Basler
  */
-public class DetailActivity extends AppCompatActivity {
+public abstract class DetailActivity extends AppCompatActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {

app/src/main/java/ch/dissem/apps/abit/Identicon.java

@@ -31,10 +31,10 @@ public class Identicon extends Drawable {
     private static final int CENTER_COLUMN = 5;
 
     private final Paint paint;
-    private int color;
+    private final int color;
-    private int background;
+    private final int background;
-    private boolean[][] fields;
+    private final boolean[][] fields;
-    private boolean chan;
+    private final boolean chan;
     private final TextPaint textPaint;
 
     public Identicon(BitmessageAddress input) {

app/src/main/java/ch/dissem/apps/abit/InputWifFragment.java

@@ -28,7 +28,6 @@ import android.view.ViewGroup;
 import android.widget.TextView;
 import android.widget.Toast;
 
-import com.github.angads25.filepicker.controller.DialogSelectionListener;
 import com.github.angads25.filepicker.model.DialogConfigs;
 import com.github.angads25.filepicker.model.DialogProperties;
 import com.github.angads25.filepicker.view.FilePickerDialog;
@@ -61,9 +60,7 @@ public class InputWifFragment extends Fragment {
         View view = inflater.inflate(R.layout.fragment_import_input, container, false);
         wifData = (TextView) view.findViewById(R.id.wif_input);
 
-        view.findViewById(R.id.next).setOnClickListener(new View.OnClickListener() {
+        view.findViewById(R.id.next).setOnClickListener(v -> {
-            @Override
-            public void onClick(View v) {
             Bundle bundle = new Bundle();
             bundle.putString(WIF_DATA, wifData.getText().toString());
 
@@ -73,7 +70,6 @@ public class InputWifFragment extends Fragment {
             getFragmentManager().beginTransaction()
                 .replace(R.id.content, fragment)
                 .commit();
-            }
         });
         return view;
     }
@@ -93,9 +89,7 @@ public class InputWifFragment extends Fragment {
         properties.extensions = null;
         FilePickerDialog dialog = new FilePickerDialog(getActivity(), properties);
         dialog.setTitle(getString(R.string.select_file_title));
-        dialog.setDialogSelectionListener(new DialogSelectionListener() {
+        dialog.setDialogSelectionListener(files -> {
-            @Override
-            public void onSelectedFilePaths(String[] files) {
             if (files.length > 0) {
                 try (InputStream in = new FileInputStream(files[0])) {
                     ByteArrayOutputStream data = new ByteArrayOutputStream();
@@ -114,7 +108,6 @@ public class InputWifFragment extends Fragment {
                     ).show();
                 }
             }
-            }
         });
         dialog.show();
         return true;

app/src/main/java/ch/dissem/apps/abit/MessageListFragment.java

@@ -130,15 +130,12 @@ public class MessageListFragment extends Fragment implements ListHolder {
         // Show the dummy content as text in a TextView.
         FloatingActionButton fab = (FloatingActionButton) rootView.findViewById(R.id
             .fab_compose_message);
-        fab.setOnClickListener(new View.OnClickListener() {
+        fab.setOnClickListener(view -> {
-            @Override
-            public void onClick(View view) {
             Intent intent = new Intent(getActivity().getApplicationContext(),
                 ComposeMessageActivity.class);
             intent.putExtra(ComposeMessageActivity.EXTRA_IDENTITY, Singleton.getIdentity
                 (getActivity()));
             startActivity(intent);
-            }
         });
 
         // touch guard manager  (this class is required to suppress scrolling while swipe-dismiss
@@ -173,7 +170,7 @@ public class MessageListFragment extends Fragment implements ListHolder {
             }
 
             @Override
-            public void onItemViewClicked(View v, boolean pinned) {
+            public void onItemViewClicked(View v) {
                 int position = recyclerView.getChildAdapterPosition(v);
                 adapter.setSelectedPosition(position);
                 if (position != RecyclerView.NO_POSITION) {

app/src/main/java/ch/dissem/apps/abit/SettingsFragment.java

@@ -46,9 +46,7 @@ public class SettingsFragment
         addPreferencesFromResource(R.xml.preferences);
 
         Preference about = findPreference("about");
-        about.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
+        about.setOnPreferenceClickListener(preference -> {
-            @Override
-            public boolean onPreferenceClick(Preference preference) {
             new LibsBuilder()
                 .withActivityTitle(getActivity().getString(R.string.about))
                 .withActivityStyle(Libs.ActivityStyle.LIGHT_DARK_TOOLBAR)
@@ -57,16 +55,12 @@ public class SettingsFragment
                 .withAboutDescription(getString(R.string.about_app))
                 .start(getActivity());
             return true;
-            }
         });
 
         Preference status = findPreference("status");
-        status.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
+        status.setOnPreferenceClickListener(preference -> {
-            @Override
-            public boolean onPreferenceClick(Preference preference) {
             startActivity(new Intent(getActivity(), StatusActivity.class));
             return true;
-            }
         });
     }
 

app/src/main/java/ch/dissem/apps/abit/adapter/AddressSelectorAdapter.java

@@ -21,7 +21,6 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.CheckBox;
-import android.widget.CompoundButton;
 import android.widget.TextView;
 
 import java.util.ArrayList;
@@ -69,20 +68,17 @@ public class AddressSelectorAdapter
 
     static class ViewHolder extends RecyclerView.ViewHolder {
         public Selectable<BitmessageAddress> data;
-        public CheckBox checkbox;
+        public final CheckBox checkbox;
-        public TextView address;
+        public final TextView address;
 
         private ViewHolder(View v) {
             super(v);
             checkbox = (CheckBox) v.findViewById(R.id.checkbox);
             address = (TextView) v.findViewById(R.id.address);
-            checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+            checkbox.setOnCheckedChangeListener((buttonView, isChecked) -> {
-                @Override
-                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 if (data != null) {
                     data.selected = isChecked;
                 }
-                }
             });
         }
     }

app/src/main/java/ch/dissem/apps/abit/adapter/SwipeableMessageAdapter.java

@@ -59,8 +59,8 @@ public class SwipeableMessageAdapter
 
     private List<Plaintext> data = Collections.emptyList();
     private EventListener eventListener;
-    private View.OnClickListener itemViewOnClickListener;
+    private final View.OnClickListener itemViewOnClickListener;
-    private View.OnClickListener swipeableViewContainerOnClickListener;
+    private final View.OnClickListener swipeableViewContainerOnClickListener;
 
     private Label label;
     private int selectedPosition;
@@ -75,12 +75,12 @@ public class SwipeableMessageAdapter
 
         void onItemArchived(Plaintext item);
 
-        void onItemViewClicked(View v, boolean pinned);
+        void onItemViewClicked(View v);
     }
 
     @SuppressWarnings("WeakerAccess")
     static class ViewHolder extends AbstractSwipeableItemViewHolder {
-        public FrameLayout container;
+        public final FrameLayout container;
         public final ImageView avatar;
         public final TextView sender;
         public final TextView subject;
@@ -102,18 +102,8 @@ public class SwipeableMessageAdapter
     }
 
     public SwipeableMessageAdapter() {
-        itemViewOnClickListener = new View.OnClickListener() {
+        itemViewOnClickListener = this::onItemViewClick;
-            @Override
+        swipeableViewContainerOnClickListener = this::onSwipeableViewContainerClick;
-            public void onClick(View v) {
-                onItemViewClick(v);
-            }
-        };
-        swipeableViewContainerOnClickListener = new View.OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                onSwipeableViewContainerClick(v);
-            }
-        };
 
         // SwipeableItemAdapter requires stable ID, and also
         // have to implement the getItemId() method appropriately.
@@ -127,14 +117,14 @@ public class SwipeableMessageAdapter
 
     private void onItemViewClick(View v) {
         if (eventListener != null) {
-            eventListener.onItemViewClicked(v, true); // pinned
+            eventListener.onItemViewClicked(v);
         }
     }
 
     private void onSwipeableViewContainerClick(View v) {
         if (eventListener != null) {
             eventListener.onItemViewClicked(
-                RecyclerViewAdapterUtils.getParentViewHolderItemView(v), false);  // not pinned
+                RecyclerViewAdapterUtils.getParentViewHolderItemView(v));
         }
     }
 

app/src/main/java/ch/dissem/apps/abit/dialog/AddIdentityDialogFragment.java

@@ -19,7 +19,6 @@ package ch.dissem.apps.abit.dialog;
 import android.annotation.SuppressLint;
 import android.app.AlertDialog;
 import android.content.Context;
-import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.AsyncTask;
 import android.os.Bundle;
@@ -61,9 +60,7 @@ public class AddIdentityDialogFragment extends AppCompatDialogFragment {
         getDialog().setTitle(R.string.add_identity);
         View view = inflater.inflate(R.layout.dialog_add_identity, container, false);
         final RadioGroup radioGroup = (RadioGroup) view.findViewById(R.id.radioGroup);
-        view.findViewById(R.id.ok).setOnClickListener(new View.OnClickListener() {
+        view.findViewById(R.id.ok).setOnClickListener(v -> {
-            @Override
-            public void onClick(View v) {
             final Context ctx = getActivity().getBaseContext();
             switch (radioGroup.getCheckedRadioButtonId()) {
                 case R.id.create_identity:
@@ -102,15 +99,8 @@ public class AddIdentityDialogFragment extends AppCompatDialogFragment {
                     return;
             }
             dismiss();
-            }
-        });
-        view.findViewById(R.id.dismiss)
-            .setOnClickListener(new View.OnClickListener() {
-                @Override
-                public void onClick(View v) {
-                    dismiss();
-                }
         });
+        view.findViewById(R.id.dismiss).setOnClickListener(v -> dismiss());
         return view;
     }
 
@@ -123,9 +113,7 @@ public class AddIdentityDialogFragment extends AppCompatDialogFragment {
         new AlertDialog.Builder(activity)
             .setTitle(R.string.add_chan)
             .setView(dialogView)
-            .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
+            .setPositiveButton(R.string.ok, (dialogInterface, i) -> {
-                @Override
-                public void onClick(DialogInterface dialogInterface, int i) {
                 TextView passphrase = (TextView) dialogView.findViewById(R.id.passphrase);
                 Toast.makeText(ctx, R.string.toast_long_running_operation,
                     Toast.LENGTH_SHORT).show();
@@ -150,7 +138,6 @@ public class AddIdentityDialogFragment extends AppCompatDialogFragment {
                         }
                     }
                 }.execute(passphrase.getText().toString());
-                }
             })
             .setNegativeButton(R.string.cancel, null)
             .show();

app/src/main/java/ch/dissem/apps/abit/listener/WifiReceiver.java

@@ -29,6 +29,7 @@ import ch.dissem.bitmessage.BitmessageContext;
 public class WifiReceiver extends BroadcastReceiver {
     @Override
     public void onReceive(Context ctx, Intent intent) {
+        if ("android.net.conn.CONNECTIVITY_CHANGE".equals(intent.getAction())) {
             if (Preferences.isWifiOnly(ctx)) {
                 BitmessageContext bmc = Singleton.getBitmessageContext(ctx);
 
@@ -37,13 +38,14 @@ public class WifiReceiver extends BroadcastReceiver {
                 }
             }
         }
+    }
 
     public static boolean isConnectedToMeteredNetwork(Context ctx) {
         NetworkInfo netInfo = getNetworkInfo(ctx);
         if (netInfo == null || !netInfo.isConnectedOrConnecting()) {
             return false;
         }
-        switch (netInfo.getType()){
+        switch (netInfo.getType()) {
             case ConnectivityManager.TYPE_ETHERNET:
             case ConnectivityManager.TYPE_WIFI:
                 return false;

app/src/main/java/ch/dissem/apps/abit/notification/ErrorNotification.java

@@ -31,7 +31,7 @@ import ch.dissem.apps.abit.R;
 public class ErrorNotification extends AbstractNotification {
     public static final int ERROR_NOTIFICATION_ID = 4;
 
-    private NotificationCompat.Builder builder;
+    private final NotificationCompat.Builder builder;
 
     public ErrorNotification(Context ctx) {
         super(ctx);

app/src/main/java/ch/dissem/apps/abit/pow/ServerPowEngine.java

@@ -17,14 +17,12 @@
 package ch.dissem.apps.abit.pow;
 
 import android.content.Context;
-import android.support.annotation.NonNull;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
-import java.util.concurrent.ThreadFactory;
 
 import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.apps.abit.synchronization.SyncAdapter;
@@ -52,21 +50,16 @@ public class ServerPowEngine implements ProofOfWorkEngine, InternalContext
 
     public ServerPowEngine(Context ctx) {
         this.ctx = ctx;
-        pool = Executors.newCachedThreadPool(new ThreadFactory() {
+        pool = Executors.newCachedThreadPool(r -> {
-            @Override
-            public Thread newThread(@NonNull Runnable r) {
             Thread thread = Executors.defaultThreadFactory().newThread(r);
             thread.setPriority(Thread.MIN_PRIORITY);
             return thread;
-            }
         });
     }
 
     @Override
     public void calculateNonce(final byte[] initialHash, final byte[] target, Callback callback) {
-        pool.execute(new Runnable() {
+        pool.execute(() -> {
-            @Override
-            public void run() {
             BitmessageAddress identity = Singleton.getIdentity(ctx);
             if (identity == null) throw new RuntimeException("No Identity for calculating POW");
 
@@ -86,7 +79,6 @@ public class ServerPowEngine implements ProofOfWorkEngine, InternalContext
             } catch (Exception e) {
                 LOG.error(e.getMessage(), e);
             }
-            }
         });
     }
 

app/src/main/java/ch/dissem/apps/abit/repository/AndroidAddressRepository.java

@@ -169,15 +169,11 @@ public class AndroidAddressRepository implements AddressRepository {
 
     @Override
     public void save(BitmessageAddress address) {
-        try {
         if (exists(address)) {
             update(address);
         } else {
             insert(address);
         }
-        } catch (IOException e) {
-            LOG.error(e.getMessage(), e);
-        }
     }
 
     private boolean exists(BitmessageAddress address) {
@@ -191,7 +187,7 @@ public class AndroidAddressRepository implements AddressRepository {
         }
     }
 
-    private void update(BitmessageAddress address) throws IOException {
+    private void update(BitmessageAddress address) {
         try {
             SQLiteDatabase db = sql.getWritableDatabase();
             // Create a new map of values, where column names are the keys
@@ -224,7 +220,7 @@ public class AndroidAddressRepository implements AddressRepository {
         }
     }
 
-    private void insert(BitmessageAddress address) throws IOException {
+    private void insert(BitmessageAddress address) {
         try {
             SQLiteDatabase db = sql.getWritableDatabase();
             // Create a new map of values, where column names are the keys

app/src/main/java/ch/dissem/apps/abit/repository/AndroidMessageRepository.java

@@ -275,14 +275,12 @@ public class AndroidMessageRepository extends AbstractMessageRepository {
             db.setTransactionSuccessful();
         } catch (SQLiteConstraintException e) {
             LOG.trace(e.getMessage(), e);
-        } catch (IOException e) {
-            LOG.error(e.getMessage(), e);
         } finally {
             db.endTransaction();
         }
     }
 
-    private void insert(SQLiteDatabase db, Plaintext message) throws IOException {
+    private void insert(SQLiteDatabase db, Plaintext message) {
         ContentValues values = new ContentValues();
         values.put(COLUMN_IV, message.getInventoryVector() == null ? null : message
             .getInventoryVector().getHash());
@@ -302,7 +300,7 @@ public class AndroidMessageRepository extends AbstractMessageRepository {
         message.setId(id);
     }
 
-    private void update(SQLiteDatabase db, Plaintext message) throws IOException {
+    private void update(SQLiteDatabase db, Plaintext message) {
         ContentValues values = new ContentValues();
         values.put(COLUMN_IV, message.getInventoryVector() == null ? null : message
             .getInventoryVector().getHash());

app/src/main/java/ch/dissem/apps/abit/repository/SqlHelper.java

@@ -27,10 +27,10 @@ import ch.dissem.apps.abit.util.Assets;
  */
 public class SqlHelper extends SQLiteOpenHelper {
     // If you change the database schema, you must increment the database version.
-    public static final int DATABASE_VERSION = 5;
+    private static final int DATABASE_VERSION = 5;
-    public static final String DATABASE_NAME = "jabit.db";
+    private static final String DATABASE_NAME = "jabit.db";
 
-    protected final Context ctx;
+    private final Context ctx;
 
     public SqlHelper(Context ctx) {
         super(ctx, DATABASE_NAME, null, DATABASE_VERSION);
@@ -65,7 +65,7 @@ public class SqlHelper extends SQLiteOpenHelper {
         }
     }
 
-    protected void executeMigration(SQLiteDatabase db, String name) {
+    private void executeMigration(SQLiteDatabase db, String name) {
         for (String statement : Assets.readSqlStatements(ctx, "db/migration/" + name + ".sql")) {
             db.execSQL(statement);
         }

app/src/main/java/ch/dissem/apps/abit/service/ProofOfWorkService.java

@@ -37,9 +37,9 @@ import static ch.dissem.apps.abit.notification.ProofOfWorkNotification.ONGOING_N
  */
 public class ProofOfWorkService extends Service {
     // Object to use as a thread-safe lock
-    private static ProofOfWorkEngine engine = new MultiThreadedPOWEngine();
+    private static final ProofOfWorkEngine engine = new MultiThreadedPOWEngine();
-    private static boolean calculating;
     private static final Queue<PowItem> queue = new LinkedList<>();
+    private static boolean calculating;
     private ProofOfWorkNotification notification;
 
     @Override

app/src/main/java/ch/dissem/apps/abit/service/ServicePowEngine.java

@@ -38,14 +38,14 @@ public class ServicePowEngine implements ProofOfWorkEngine {
     private final Context ctx;
 
     private static final Object lock = new Object();
-    private Queue<PowItem> queue = new LinkedList<>();
+    private final Queue<PowItem> queue = new LinkedList<>();
     private PowBinder service;
 
     public ServicePowEngine(Context ctx) {
         this.ctx = ctx;
     }
 
-    private ServiceConnection connection = new ServiceConnection() {
+    private final ServiceConnection connection = new ServiceConnection() {
         @Override
         public void onServiceConnected(ComponentName name, IBinder service) {
             synchronized (lock) {

app/src/main/java/ch/dissem/apps/abit/util/Preferences.java

@@ -20,9 +20,6 @@ import android.content.Context;
 import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.net.InetAddress;