Reformat code, and move other LiveDatas to their own respective services.

NOTE: As of this commit, the app logs the wallet seed for development purposes.

app/src/main/java/com/m2049r/xmrwallet/MainActivity.java

@@ -1,27 +1,25 @@
 package com.m2049r.xmrwallet;
 
 import android.os.Bundle;
+
 import androidx.appcompat.app.AppCompatActivity;
-import androidx.lifecycle.LiveData;
+
-import androidx.lifecycle.MutableLiveData;
-import com.m2049r.xmrwallet.model.TransactionInfo;
 import com.m2049r.xmrwallet.model.Wallet;
 import com.m2049r.xmrwallet.model.WalletManager;
+import com.m2049r.xmrwallet.service.AddressService;
+import com.m2049r.xmrwallet.service.BalanceService;
+import com.m2049r.xmrwallet.service.HistoryService;
 import com.m2049r.xmrwallet.service.MoneroHandlerThread;
 import com.m2049r.xmrwallet.service.TxService;
+
 import java.io.File;
-import java.util.List;
 
 public class MainActivity extends AppCompatActivity implements MoneroHandlerThread.Listener {
-    private final MutableLiveData<String> _address = new MutableLiveData<>("");
-    public LiveData<String> address = _address;
-    private final MutableLiveData<Long> _balance = new MutableLiveData<>(0L);
-    public LiveData<Long> balance = _balance;
-    private final MutableLiveData<List<TransactionInfo>> _history = new MutableLiveData<>();
-    public LiveData<List<TransactionInfo>> history = _history;
-
     private MoneroHandlerThread thread = null;
     private TxService txService = null;
+    private BalanceService balanceService = null;
+    private AddressService addressService = null;
+    private HistoryService historyService = null;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -37,7 +35,7 @@ public class MainActivity extends AppCompatActivity implements MoneroHandlerThre
     private void init() {
         File walletFile = new File(getApplicationInfo().dataDir, "xmr_wallet");
         Wallet wallet = null;
-        if(walletFile.exists()) {
+        if (walletFile.exists()) {
             wallet = WalletManager.getInstance().openWallet(walletFile.getAbsolutePath(), "");
         } else {
             wallet = WalletManager.getInstance().createWallet(walletFile, "", "English", 0);
@@ -46,17 +44,15 @@ public class MainActivity extends AppCompatActivity implements MoneroHandlerThre
         thread = new MoneroHandlerThread("WalletService", wallet, this);
         thread.start();
         this.txService = new TxService(this, thread);
+        this.balanceService = new BalanceService(this, thread);
+        this.addressService = new AddressService(this, thread);
+        this.historyService = new HistoryService(this, thread);
     }
 
     @Override
     public void onRefresh() {
-        WalletManager walletManager = WalletManager.getInstance();
+        this.historyService.refreshHistory();
-        Wallet wallet = walletManager.getWallet();
+        this.balanceService.refreshBalance();
-        if(wallet != null) {
+        this.addressService.refreshAddress();
-            String address = wallet.getLastSubaddress(0);
-            _history.postValue(wallet.getHistory().getAll());
-            _balance.postValue(wallet.getBalance());
-            _address.postValue(address);
-        }
     }
 }

app/src/main/java/com/m2049r/xmrwallet/data/Node.java

@@ -110,7 +110,7 @@ public class Node {
     private boolean favourite = false;
     @Getter
     @Setter
-    private boolean selected = false;
+    private final boolean selected = false;
 
     @Override
     public int hashCode() {
@@ -144,13 +144,13 @@ public class Node {
         if ((nodeString == null) || nodeString.isEmpty())
             throw new IllegalArgumentException("daemon is empty");
         String daemonAddress;
-        String a[] = nodeString.split("@");
+        String[] a = nodeString.split("@");
         if (a.length == 1) { // no credentials
             daemonAddress = a[0];
             username = "";
             password = "";
         } else if (a.length == 2) { // credentials
-            String userPassword[] = a[0].split(":");
+            String[] userPassword = a[0].split(":");
             if (userPassword.length != 2)
                 throw new IllegalArgumentException("User:Password invalid");
             username = userPassword[0];
@@ -164,12 +164,12 @@ public class Node {
             throw new IllegalArgumentException("Too many @");
         }
 
-        String daParts[] = daemonAddress.split("/");
+        String[] daParts = daemonAddress.split("/");
         if ((daParts.length > 3) || (daParts.length < 1))
             throw new IllegalArgumentException("Too many '/' or too few");
 
         daemonAddress = daParts[0];
-        String da[] = daemonAddress.split(":");
+        String[] da = daemonAddress.split(":");
         if ((da.length > 2) || (da.length < 1))
             throw new IllegalArgumentException("Too many ':' or too few");
         String host = da[0];

app/src/main/java/com/m2049r/xmrwallet/data/NodeInfo.java

@@ -21,8 +21,6 @@ import android.text.Html;
 import android.text.Spanned;
 import android.widget.TextView;
 
-import androidx.core.content.ContextCompat;
-
 import com.m2049r.levin.scanner.LevinPeer;
 import com.m2049r.xmrwallet.R;
 import com.m2049r.xmrwallet.util.NetCipherHelper;
@@ -65,7 +63,7 @@ public class NodeInfo extends Node {
     private boolean tested = false;
     @Getter
     @Setter
-    private boolean selecting = false;
+    private final boolean selecting = false;
 
     public void clear() {
         height = 0;

app/src/main/java/com/m2049r/xmrwallet/data/TxDataBtc.java

@@ -95,7 +95,7 @@ public class TxDataBtc extends TxData {
         if (crypto.isCasefull()) { // compare as-is
             return address.equals(btcAddress);
         } else { // normalize & compare (e.g. ETH with and without checksum capitals
-            return address.toLowerCase().equals(btcAddress.toLowerCase());
+            return address.equalsIgnoreCase(btcAddress);
         }
     }
 }

app/src/main/java/com/m2049r/xmrwallet/fragment/home/HomeFragment.java

@@ -1,20 +1,6 @@
 package com.m2049r.xmrwallet.fragment.home;
 
-import androidx.fragment.app.FragmentActivity;
-import androidx.fragment.app.FragmentManager;
-import androidx.lifecycle.Observer;
-import androidx.lifecycle.ViewModelProvider;
-
-import android.app.Activity;
-import android.graphics.Bitmap;
 import android.os.Bundle;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.fragment.app.Fragment;
-import androidx.navigation.NavController;
-import androidx.navigation.fragment.NavHostFragment;
-
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -24,24 +10,20 @@ import android.widget.ImageView;
 import android.widget.TextView;
 import android.widget.Toast;
 
-import com.google.zxing.BarcodeFormat;
+import androidx.annotation.NonNull;
-import com.google.zxing.EncodeHintType;
+import androidx.annotation.Nullable;
-import com.google.zxing.WriterException;
+import androidx.fragment.app.Fragment;
-import com.google.zxing.common.BitMatrix;
+import androidx.fragment.app.FragmentActivity;
-import com.google.zxing.qrcode.QRCodeWriter;
+import androidx.fragment.app.FragmentManager;
-import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import androidx.lifecycle.ViewModelProvider;
+import androidx.navigation.fragment.NavHostFragment;
+
 import com.m2049r.xmrwallet.MainActivity;
 import com.m2049r.xmrwallet.R;
-import com.m2049r.xmrwallet.data.BarcodeData;
-import com.m2049r.xmrwallet.data.Crypto;
 import com.m2049r.xmrwallet.model.Wallet;
+import com.m2049r.xmrwallet.service.AddressService;
+import com.m2049r.xmrwallet.service.BalanceService;
 import com.m2049r.xmrwallet.service.TxService;
-import com.m2049r.xmrwallet.util.Helper;
-
-import java.util.HashMap;
-import java.util.Map;
-
-import timber.log.Timber;
 
 public class HomeFragment extends Fragment {
 
@@ -58,7 +40,7 @@ public class HomeFragment extends Fragment {
         super.onViewCreated(view, savedInstanceState);
         mViewModel = new ViewModelProvider(this).get(HomeViewModel.class);
         MainActivity mainActivity = (MainActivity) getActivity();
-        if(mainActivity == null) return;
+        if (mainActivity == null) return;
 
         ImageView settingsImageView = view.findViewById(R.id.settings_imageview);
         ImageView addressImageView = view.findViewById(R.id.monero_qr_imageview);
@@ -68,14 +50,14 @@ public class HomeFragment extends Fragment {
         EditText amountEditText = view.findViewById(R.id.amount_edittext);
         Button sendButton = view.findViewById(R.id.send_button);
 
-        mainActivity.address.observe(getViewLifecycleOwner(), addr -> {
+        AddressService.getInstance().address.observe(getViewLifecycleOwner(), addr -> {
-            if(!addr.isEmpty()) {
+            if (!addr.isEmpty()) {
                 addressTextView.setText(addr);
                 addressImageView.setImageBitmap(mViewModel.generate(addr, 256, 256));
             }
         });
 
-        mainActivity.balance.observe(getViewLifecycleOwner(), balance -> {
+        BalanceService.getInstance().balance.observe(getViewLifecycleOwner(), balance -> {
             balanceTextView.setText(getString(R.string.wallet_balance_text, Wallet.getDisplayAmount(balance)));
         });
 
@@ -93,12 +75,12 @@ public class HomeFragment extends Fragment {
             String address = addressEditText.getText().toString().trim();
             String amount = amountEditText.getText().toString().trim();
             boolean validAddress = Wallet.isAddressValid(address);
-            if(validAddress && !amount.isEmpty()) {
+            if (validAddress && !amount.isEmpty()) {
                 sendButton.setEnabled(false);
                 TxService.getInstance().sendTx(address, amount);
-            } else if(!validAddress) {
+            } else if (!validAddress) {
                 Toast.makeText(getActivity(), getString(R.string.send_address_invalid), Toast.LENGTH_SHORT).show();
-            } else if(amount.isEmpty()) {
+            } else if (amount.isEmpty()) {
                 Toast.makeText(getActivity(), getString(R.string.send_amount_empty), Toast.LENGTH_SHORT).show();
             }
         });
@@ -106,11 +88,11 @@ public class HomeFragment extends Fragment {
 
     private void navigate(int destination) {
         FragmentActivity activity = getActivity();
-        if(activity != null) {
+        if (activity != null) {
             FragmentManager fm = activity.getSupportFragmentManager();
             NavHostFragment navHostFragment =
                     (NavHostFragment) fm.findFragmentById(R.id.nav_host_fragment);
-            if(navHostFragment != null) {
+            if (navHostFragment != null) {
                 navHostFragment.getNavController().navigate(destination);
             }
         }

app/src/main/java/com/m2049r/xmrwallet/fragment/home/HomeViewModel.java

@@ -3,12 +3,14 @@ package com.m2049r.xmrwallet.fragment.home;
 import android.graphics.Bitmap;
 
 import androidx.lifecycle.ViewModel;
+
 import com.google.zxing.BarcodeFormat;
 import com.google.zxing.EncodeHintType;
 import com.google.zxing.WriterException;
 import com.google.zxing.common.BitMatrix;
 import com.google.zxing.qrcode.QRCodeWriter;
 import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+
 import java.util.HashMap;
 import java.util.Map;
 

app/src/main/java/com/m2049r/xmrwallet/fragment/settings/SettingsFragment.java

@@ -4,22 +4,13 @@ import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.Button;
-import android.widget.EditText;
-import android.widget.ImageView;
-import android.widget.TextView;
-import android.widget.Toast;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.fragment.app.Fragment;
-import androidx.fragment.app.FragmentActivity;
-import androidx.fragment.app.FragmentManager;
 import androidx.lifecycle.ViewModelProvider;
-import androidx.navigation.fragment.NavHostFragment;
 
 import com.m2049r.xmrwallet.R;
-import com.m2049r.xmrwallet.model.Wallet;
 
 public class SettingsFragment extends Fragment {
 

app/src/main/java/com/m2049r/xmrwallet/fragment/settings/SettingsViewModel.java

@@ -2,6 +2,6 @@ package com.m2049r.xmrwallet.fragment.settings;
 
 import androidx.lifecycle.ViewModel;
 
-public class SettingsViewModel extends ViewModel{
+public class SettingsViewModel extends ViewModel {
 
 }

app/src/main/java/com/m2049r/xmrwallet/ledger/Instruction.java

@@ -147,7 +147,7 @@ public enum Instruction {
         return (byte) (value & 0xFF);
     }
 
-    private int value;
+    private final int value;
 
     Instruction(int value) {
         this.value = value;

app/src/main/java/com/m2049r/xmrwallet/ledger/Ledger.java

@@ -45,7 +45,7 @@ public class Ledger {
     private static final byte PROTOCOL_VERSION = 0x03;
     public static final int SW_OK = 0x9000;
     public static final int SW_INS_NOT_SUPPORTED = 0x6D00;
-    public static final int OK[] = {SW_OK};
+    public static final int[] OK = {SW_OK};
     public static final int MINIMUM_LEDGER_VERSION = (1 << 16) + (8 << 8) + (0); // 1.6.0
 
     public static UsbDevice findDevice(UsbManager usbManager) {
@@ -153,7 +153,7 @@ public class Ledger {
         return result;
     }
 
-    private byte[] exchangeCheck(byte[] apdu, int acceptedSW[]) throws BTChipException {
+    private byte[] exchangeCheck(byte[] apdu, int[] acceptedSW) throws BTChipException {
         byte[] response = exchange(apdu);
         if (acceptedSW == null) {
             return response;
@@ -166,7 +166,7 @@ public class Ledger {
         throw new BTChipException("Invalid status", lastSW);
     }
 
-    private byte[] exchangeApduNoOpt(Instruction instruction, byte[] data, int acceptedSW[])
+    private byte[] exchangeApduNoOpt(Instruction instruction, byte[] data, int[] acceptedSW)
             throws BTChipException {
         byte[] apdu = new byte[data.length + 6];
         apdu[0] = PROTOCOL_VERSION;

app/src/main/java/com/m2049r/xmrwallet/model/NetworkType.java

@@ -37,7 +37,7 @@ public enum NetworkType {
         return value;
     }
 
-    private int value;
+    private final int value;
 
     NetworkType(int value) {
         this.value = value;

app/src/main/java/com/m2049r/xmrwallet/model/PendingTransaction.java

@@ -58,7 +58,7 @@ public class PendingTransaction {
             return value;
         }
 
-        private int value;
+        private final int value;
 
         Priority(int value) {
             this.value = value;

app/src/main/java/com/m2049r/xmrwallet/model/TransactionHistory.java

@@ -27,7 +27,7 @@ public class TransactionHistory {
         System.loadLibrary("monerujo");
     }
 
-    private long handle;
+    private final long handle;
 
     int accountIndex;
 

app/src/main/java/com/m2049r/xmrwallet/model/WalletListener.java

@@ -19,6 +19,7 @@ package com.m2049r.xmrwallet.model;
 public interface WalletListener {
     /**
      * moneySpent - called when money spent
+     *
      * @param txId   - transaction id
      * @param amount - tvAmount
      */
@@ -26,6 +27,7 @@ public interface WalletListener {
 
     /**
      * moneyReceived - called when money received
+     *
      * @param txId   - transaction id
      * @param amount - tvAmount
      */
@@ -33,6 +35,7 @@ public interface WalletListener {
 
     /**
      * unconfirmedMoneyReceived - called when payment arrived in tx pool
+     *
      * @param txId   - transaction id
      * @param amount - tvAmount
      */
@@ -40,6 +43,7 @@ public interface WalletListener {
 
     /**
      * newBlock      - called when new block received
+     *
      * @param height - block height
      */
     void newBlock(long height);

app/src/main/java/com/m2049r/xmrwallet/service/AddressService.java

@@ -0,0 +1,27 @@
+package com.m2049r.xmrwallet.service;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import com.m2049r.xmrwallet.MainActivity;
+import com.m2049r.xmrwallet.model.WalletManager;
+
+public class AddressService extends ServiceBase {
+    public static AddressService instance = null;
+
+    public static AddressService getInstance() {
+        return instance;
+    }
+
+    private final MutableLiveData<String> _address = new MutableLiveData<>("");
+    public LiveData<String> address = _address;
+
+    public AddressService(MainActivity mainActivity, MoneroHandlerThread thread) {
+        super(mainActivity, thread);
+        instance = this;
+    }
+
+    public void refreshAddress() {
+        _address.postValue(WalletManager.getInstance().getWallet().getAddress());
+    }
+}

app/src/main/java/com/m2049r/xmrwallet/service/BalanceService.java

@@ -0,0 +1,27 @@
+package com.m2049r.xmrwallet.service;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import com.m2049r.xmrwallet.MainActivity;
+import com.m2049r.xmrwallet.model.WalletManager;
+
+public class BalanceService extends ServiceBase {
+    public static BalanceService instance = null;
+
+    public static BalanceService getInstance() {
+        return instance;
+    }
+
+    private final MutableLiveData<Long> _balance = new MutableLiveData<>(0L);
+    public LiveData<Long> balance = _balance;
+
+    public BalanceService(MainActivity mainActivity, MoneroHandlerThread thread) {
+        super(mainActivity, thread);
+        instance = this;
+    }
+
+    public void refreshBalance() {
+        _balance.postValue(WalletManager.getInstance().getWallet().getBalance());
+    }
+}

app/src/main/java/com/m2049r/xmrwallet/service/HistoryService.java

@@ -0,0 +1,34 @@
+package com.m2049r.xmrwallet.service;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+import com.m2049r.xmrwallet.MainActivity;
+import com.m2049r.xmrwallet.model.TransactionInfo;
+import com.m2049r.xmrwallet.model.WalletManager;
+
+import java.util.List;
+
+public class HistoryService extends ServiceBase {
+    public static HistoryService instance = null;
+
+    public static HistoryService getInstance() {
+        return instance;
+    }
+
+    private final MutableLiveData<List<TransactionInfo>> _history = new MutableLiveData<>();
+    public LiveData<List<TransactionInfo>> history = _history;
+
+    public HistoryService(MainActivity mainActivity, MoneroHandlerThread thread) {
+        super(mainActivity, thread);
+        instance = this;
+    }
+
+    public void refreshHistory() {
+        _history.postValue(WalletManager.getInstance().getWallet().getHistory().getAll());
+    }
+
+    public List<TransactionInfo> getHistory() {
+        return WalletManager.getInstance().getWallet().getHistory().getAll();
+    }
+}

app/src/main/java/com/m2049r/xmrwallet/service/MoneroHandlerThread.java

@@ -17,18 +17,9 @@
 
 package com.m2049r.xmrwallet.service;
 
-import android.os.Handler;
-import android.os.Looper;
-import android.os.Message;
-import android.os.Process;
-
-import androidx.lifecycle.LiveData;
-import androidx.lifecycle.MutableLiveData;
-
 import com.m2049r.xmrwallet.data.DefaultNodes;
 import com.m2049r.xmrwallet.data.Node;
 import com.m2049r.xmrwallet.data.TxData;
-import com.m2049r.xmrwallet.fragment.home.HomeViewModel;
 import com.m2049r.xmrwallet.model.PendingTransaction;
 import com.m2049r.xmrwallet.model.Wallet;
 import com.m2049r.xmrwallet.model.WalletListener;
@@ -64,15 +55,20 @@ public class MoneroHandlerThread extends Thread implements WalletListener {
     }
 
     @Override
-    public void moneySpent(String txId, long amount) {}
+    public void moneySpent(String txId, long amount) {
+    }
+
     @Override
-    public void moneyReceived(String txId, long amount) {}
+    public void moneyReceived(String txId, long amount) {
+    }
+
     @Override
-    public void unconfirmedMoneyReceived(String txId, long amount) {}
+    public void unconfirmedMoneyReceived(String txId, long amount) {
+    }
 
     @Override
     public void newBlock(long height) {
-        if(height % 1000 == 0) {
+        if (height % 1000 == 0) {
             refresh();
         }
     }

app/src/main/java/com/m2049r/xmrwallet/service/ServiceBase.java

@@ -3,8 +3,8 @@ package com.m2049r.xmrwallet.service;
 import com.m2049r.xmrwallet.MainActivity;
 
 public class ServiceBase {
-    private MainActivity mainActivity;
+    private final MainActivity mainActivity;
-    private MoneroHandlerThread thread;
+    private final MoneroHandlerThread thread;
 
     public ServiceBase(MainActivity mainActivity, MoneroHandlerThread thread) {
         this.mainActivity = mainActivity;

app/src/main/java/com/m2049r/xmrwallet/service/TxService.java

@@ -5,10 +5,11 @@ import com.m2049r.xmrwallet.livedata.SingleLiveEvent;
 
 public class TxService extends ServiceBase {
     public static TxService instance = null;
+
     public static TxService getInstance() {
         return instance;
     }
-    
+
     private final SingleLiveEvent _clearSendEvent = new SingleLiveEvent();
     public SingleLiveEvent clearSendEvent = _clearSendEvent;
 
@@ -19,7 +20,7 @@ public class TxService extends ServiceBase {
 
     public void sendTx(String address, String amount) {
         boolean success = this.getThread().sendTx(address, amount);
-        if(success) {
+        if (success) {
             _clearSendEvent.call();
         }
     }

app/src/main/java/com/m2049r/xmrwallet/util/Helper.java

@@ -30,31 +30,19 @@ import android.graphics.Canvas;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.VectorDrawable;
-import android.hardware.fingerprint.FingerprintManager;
 import android.os.AsyncTask;
-import android.os.Build;
-import android.os.CancellationSignal;
 import android.os.StrictMode;
 import android.system.ErrnoException;
 import android.system.Os;
-import android.text.Editable;
-import android.text.TextWatcher;
-import android.view.KeyEvent;
-import android.view.LayoutInflater;
 import android.view.View;
 import android.view.WindowManager;
 import android.view.animation.Animation;
 import android.view.animation.AnimationUtils;
-import android.view.inputmethod.EditorInfo;
 import android.view.inputmethod.InputMethodManager;
-import android.widget.Button;
-import android.widget.TextView;
 
 import androidx.appcompat.app.AlertDialog;
 import androidx.core.content.ContextCompat;
 
-import com.google.android.material.dialog.MaterialAlertDialogBuilder;
-import com.google.android.material.textfield.TextInputLayout;
 import com.m2049r.xmrwallet.BuildConfig;
 import com.m2049r.xmrwallet.R;
 import com.m2049r.xmrwallet.data.Crypto;
@@ -68,9 +56,7 @@ import java.math.BigInteger;
 import java.net.MalformedURLException;
 import java.net.SocketTimeoutException;
 import java.net.URL;
-import java.util.Calendar;
 import java.util.Locale;
-import java.util.concurrent.atomic.AtomicBoolean;
 
 import javax.net.ssl.HttpsURLConnection;
 

app/src/main/java/com/m2049r/xmrwallet/util/NetCipherHelper.java

@@ -155,7 +155,7 @@ public class NetCipherHelper implements StatusCallback {
         DISABLED,
         NOT_INSTALLED,
         NOT_ENABLED,
-        UNKNOWN;
+        UNKNOWN
     }
 
     private Status status = Status.UNKNOWN;

app/src/main/java/com/m2049r/xmrwallet/util/NightmodeHelper.java

@@ -18,7 +18,6 @@ package com.m2049r.xmrwallet.util;
 
 import android.annotation.SuppressLint;
 import android.content.Context;
-import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
 
 import androidx.appcompat.app.AppCompatDelegate;

app/src/main/java/com/m2049r/xmrwallet/util/OpenAliasHelper.java

@@ -38,6 +38,7 @@ import org.xbill.DNS.Type;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -107,7 +108,7 @@ public class OpenAliasHelper {
                 SimpleResolver sr = new SimpleResolver(DNSSEC_SERVERS[new Random().nextInt(DNSSEC_SERVERS.length)]);
                 ValidatingResolver vr = new ValidatingResolver(sr);
                 vr.setTimeout(0, DNS_LOOKUP_TIMEOUT);
-                vr.loadTrustAnchors(new ByteArrayInputStream(ROOT.getBytes("ASCII")));
+                vr.loadTrustAnchors(new ByteArrayInputStream(ROOT.getBytes(StandardCharsets.US_ASCII)));
                 Record qr = Record.newRecord(Name.fromConstantString(name + "."), Type.TXT, DClass.IN);
                 Message response = vr.send(Message.newQuery(qr));
                 final int rcode = response.getRcode();

app/src/main/java/com/m2049r/xmrwallet/util/RestoreHeight.java

@@ -41,7 +41,7 @@ public class RestoreHeight {
         return Singleton;
     }
 
-    private Map<String, Long> blockheight = new HashMap<>();
+    private final Map<String, Long> blockheight = new HashMap<>();
 
     RestoreHeight() {
         blockheight.put("2014-05-01", 18844L);

app/src/main/java/com/m2049r/xmrwallet/util/validator/BitcoinAddressValidator.java

@@ -213,8 +213,6 @@ public class BitcoinAddressValidator {
 
         if (remainderSize >= 5) return false;
         // ignore checksum at end and get last byte of program
-        if ((data[data.length - 1 - 6] & ((1 << remainderSize) - 1)) != 0) return false;
+        return (data[data.length - 1 - 6] & ((1 << remainderSize) - 1)) == 0;
-
-        return true;
     }
 }