Quick cleanup across the board

- Clean up imports
- Adjust method visibility
- Drop in NonNull annotations where needed
- Prevent potential NPEs from nulled getActivity calls
- Remove unused methods

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

app/src/main/java/com/wireguard/android/backend/GoBackend.java

@@ -5,22 +5,18 @@ import android.content.Intent;
 import android.os.ParcelFileDescriptor;
 import android.support.v4.util.ArraySet;
 import android.util.Log;
-import android.util.Pair;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.model.Tunnel.State;
 import com.wireguard.android.model.Tunnel.Statistics;
-import com.wireguard.android.model.TunnelManager;
 import com.wireguard.config.Config;
 import com.wireguard.config.IPCidr;
 import com.wireguard.config.Interface;
 import com.wireguard.config.Peer;
 import com.wireguard.crypto.KeyEncoding;
 
-import java.net.Inet4Address;
 import java.net.InetAddress;
-import java.net.InetSocketAddress;
 import java.util.Collections;
 import java.util.Formatter;
 import java.util.Set;
@@ -45,7 +41,7 @@ public final class GoBackend implements Backend {
         this.context = context;
     }
 
-    public void startVpnService() {
+    private void startVpnService() {
         context.startService(new Intent(context, VpnService.class));
     }
 

app/src/main/java/com/wireguard/android/fragment/TunnelDetailFragment.java

@@ -1,6 +1,7 @@
 package com.wireguard.android.fragment;
 
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -33,7 +34,7 @@ public class TunnelDetailFragment extends BaseFragment {
     }
 
     @Override
-    public View onCreateView(final LayoutInflater inflater, final ViewGroup container,
+    public View onCreateView(@NonNull final LayoutInflater inflater, final ViewGroup container,
                              final Bundle savedInstanceState) {
         super.onCreateView(inflater, container, savedInstanceState);
         binding = TunnelDetailFragmentBinding.inflate(inflater, container, false);

app/src/main/java/com/wireguard/android/fragment/TunnelEditorFragment.java

@@ -5,6 +5,7 @@ import android.content.Context;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.support.annotation.NonNull;
 import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.Menu;
@@ -101,7 +102,7 @@ public class TunnelEditorFragment extends BaseFragment {
     }
 
     @Override
-    public View onCreateView(final LayoutInflater inflater, final ViewGroup container,
+    public View onCreateView(@NonNull final LayoutInflater inflater, final ViewGroup container,
                              final Bundle savedInstanceState) {
         super.onCreateView(inflater, container, savedInstanceState);
         binding = TunnelEditorFragmentBinding.inflate(inflater, container, false);
@@ -118,6 +119,7 @@ public class TunnelEditorFragment extends BaseFragment {
     private void onFinished() {
         // Hide the keyboard; it rarely goes away on its own.
         final Activity activity = getActivity();
+        if (activity == null) return;
         final View focusedView = activity.getCurrentFocus();
         if (focusedView != null) {
             final Object service = activity.getSystemService(Context.INPUT_METHOD_SERVICE);
@@ -174,7 +176,7 @@ public class TunnelEditorFragment extends BaseFragment {
     }
 
     @Override
-    public void onSaveInstanceState(final Bundle outState) {
+    public void onSaveInstanceState(@NonNull final Bundle outState) {
         outState.putParcelable(KEY_LOCAL_CONFIG, localConfig);
         outState.putString(KEY_ORIGINAL_NAME, originalName);
         super.onSaveInstanceState(outState);

app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java

@@ -9,6 +9,7 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.OpenableColumns;
+import android.support.annotation.NonNull;
 import android.util.Log;
 import android.util.SparseBooleanArray;
 import android.view.ActionMode;
@@ -110,7 +111,7 @@ public class TunnelListFragment extends BaseFragment {
     }
 
     @Override
-    public View onCreateView(final LayoutInflater inflater, final ViewGroup container,
+    public View onCreateView(@NonNull final LayoutInflater inflater, final ViewGroup container,
                              final Bundle savedInstanceState) {
         super.onCreateView(inflater, container, savedInstanceState);
         binding = TunnelListFragmentBinding.inflate(inflater, container, false);
@@ -220,6 +221,7 @@ public class TunnelListFragment extends BaseFragment {
         @Override
         public boolean onCreateActionMode(final ActionMode mode, final Menu menu) {
             actionMode = mode;
+            if (getActivity() != null)
                 resources = getActivity().getResources();
             tunnelList = binding.tunnelList;
             mode.getMenuInflater().inflate(R.menu.tunnel_list_action_mode, menu);

app/src/main/java/com/wireguard/android/model/Tunnel.java

@@ -37,8 +37,8 @@ public class Tunnel extends BaseObservable implements Keyed<String> {
         this.state = state;
     }
 
-    public static boolean isNameValid(@NonNull final CharSequence name) {
+    public static boolean isNameInvalid(@NonNull final CharSequence name) {
-        return NAME_PATTERN.matcher(name).matches();
+        return !NAME_PATTERN.matcher(name).matches();
     }
 
     public CompletionStage<Void> delete() {

app/src/main/java/com/wireguard/android/model/TunnelManager.java

@@ -66,7 +66,7 @@ public final class TunnelManager extends BaseObservable {
     }
 
     public CompletionStage<Tunnel> create(@NonNull final String name, final Config config) {
-        if (!Tunnel.isNameValid(name))
+        if (Tunnel.isNameInvalid(name))
             return CompletableFuture.failedFuture(new IllegalArgumentException("Invalid name"));
         if (tunnels.containsKey(name)) {
             final String message = "Tunnel " + name + " already exists";
@@ -190,7 +190,7 @@ public final class TunnelManager extends BaseObservable {
     }
 
     CompletionStage<String> setTunnelName(final Tunnel tunnel, final String name) {
-        if (!Tunnel.isNameValid(name))
+        if (Tunnel.isNameInvalid(name))
             return CompletableFuture.failedFuture(new IllegalArgumentException("Invalid name"));
         if (tunnels.containsKey(name)) {
             final String message = "Tunnel " + name + " already exists";

app/src/main/java/com/wireguard/android/preference/ToolsInstallerPreference.java

@@ -30,10 +30,6 @@ public class ToolsInstallerPreference extends Preference {
         toolsInstaller = applicationComponent.getToolsInstaller();
     }
 
-    public ToolsInstallerPreference(final Context context) {
-        this(context, null);
-    }
-
     @Override
     public CharSequence getSummary() {
         return getContext().getString(state.messageResourceId);

app/src/main/java/com/wireguard/android/util/AsyncWorker.java

@@ -22,7 +22,7 @@ public class AsyncWorker {
     private final Handler handler;
 
     @Inject
-    public AsyncWorker(final Executor executor, @ApplicationHandler final Handler handler) {
+    AsyncWorker(final Executor executor, @ApplicationHandler final Handler handler) {
         this.executor = executor;
         this.handler = handler;
     }