cleanup and fixed unwanted races

app/src/main/java/ru/vtosters/lite/hooks/AdBlockHook.java

@@ -339,7 +339,10 @@ public class AdBlockHook {
             return true;
         }
 
-        var whitelist = AndroidUtils.getDefaultPrefs().getStringSet("whitelisted_filters_groups", Collections.synchronizedSet(new LinkedHashSet<>()));
+        var whitelist = AndroidUtils.getDefaultPrefs().getStringSet(
+                "whitelisted_filters_groups",
+                Collections.emptySet()
+        );
 
         return whitelist.contains(id);
     }
@@ -351,7 +354,10 @@ public class AdBlockHook {
             id = String.valueOf(list.optInt("source_id"));
         }
 
-        var whitelist = AndroidUtils.getDefaultPrefs().getStringSet("whitelisted_ad_groups", Collections.synchronizedSet(new LinkedHashSet<>()));
+        var whitelist = AndroidUtils.getDefaultPrefs().getStringSet(
+                "whitelisted_ad_groups",
+                Collections.emptySet()
+        );
 
         return whitelist.contains(id);
     }

app/src/main/java/ru/vtosters/lite/hooks/JsonInjectors.java

@@ -336,36 +336,34 @@ public class JsonInjectors {
     public static JSONArray newsfeedlist(JSONArray items) throws JSONException {
         var selectedItems = getDefaultPrefs().getString("news_feed_selected_items", "");
         var filtersSet = getDefaultPrefs().getStringSet("news_feed_items_set", null);
-        var mutableFiltersSet = Collections.synchronizedSet(new LinkedHashSet<String>());
+        var mutableFiltersSet = new LinkedHashSet<String>();
         if (filtersSet != null)
             mutableFiltersSet.addAll(filtersSet);
 
-        synchronized (mutableFiltersSet) {
-            for (int i = 0; i < items.length(); i++) {
-                var item = items.optJSONObject(i);
-                if (item == null) continue;
+        for (int i = 0; i < items.length(); i++) {
+            var item = items.optJSONObject(i);
+            if (item == null) continue;
 
-                var id = item.optString("id");
-                var title = item.optString("title");
+            var id = item.optString("id");
+            var title = item.optString("title");
 
-                if (TextUtils.isEmpty(id) || TextUtils.isEmpty(title)
-                        // this items not working
-                        || id.equals("kpop") || id.equals("foryou")
-                        || id.equals("qazaqstan") || id.equals("podcasts"))
-                    continue;
+            if (TextUtils.isEmpty(id) || TextUtils.isEmpty(title)
+                    // this items not working
+                    || id.equals("kpop") || id.equals("foryou")
+                    || id.equals("qazaqstan") || id.equals("podcasts"))
+                continue;
 
-                mutableFiltersSet.add(id + "|" + title);
+            mutableFiltersSet.add(id + "|" + title);
 
-                var hide = selectedItems.contains(id);
+            var hide = selectedItems.contains(id);
 
-                Log.d("NewsfeedList", "Added list " + id + " to feed");
-                item.put("is_hidden", hide)
-                        .put("is_unavailable", hide);
-                if (dev()) Log.d("NewsfeedListInj", "Unlocked " + id + " in newsfeed list");
-            }
-            getDefaultPrefs().edit().putStringSet("news_feed_items_set", mutableFiltersSet)
-                    .apply();
+            Log.d("NewsfeedList", "Added list " + id + " to feed");
+            item.put("is_hidden", hide)
+                    .put("is_unavailable", hide);
+            if (dev()) Log.d("NewsfeedListInj", "Unlocked " + id + " in newsfeed list");
         }
+        getDefaultPrefs().edit().putStringSet("news_feed_items_set", mutableFiltersSet)
+                .apply();
 
         return items;
     }

app/src/main/java/ru/vtosters/lite/hooks/NewsfeedHook.java

@@ -70,19 +70,25 @@ public class NewsfeedHook {
     }
 
     public static boolean isWhitelistedFilter(ExtendedCommunityProfile eup) {
-        return getDefaultPrefs().getStringSet("whitelisted_filters_groups", Collections.synchronizedSet(new LinkedHashSet<>())).contains(String.valueOf(AccountManagerUtils.getUserID(eup)));
+        return getDefaultPrefs().getStringSet(
+                "whitelisted_filters_groups", Collections.emptySet()
+        ).contains(String.valueOf(AccountManagerUtils.getUserID(eup)));
     }
 
     public static boolean isWhitelistedAd(ExtendedCommunityProfile eup) {
-        return getDefaultPrefs().getStringSet("whitelisted_ad_groups", Collections.synchronizedSet(new LinkedHashSet<>())).contains(String.valueOf(AccountManagerUtils.getUserID(eup)));
+        return getDefaultPrefs().getStringSet(
+                "whitelisted_ad_groups",
+                Collections.emptySet()
+        ).contains(String.valueOf(AccountManagerUtils.getUserID(eup)));
     }
 
     public static void setWhitelistedFilter(ExtendedCommunityProfile eup, boolean needWhitelist) {
-        var mutableAdsSet = Collections.synchronizedSet(new LinkedHashSet<String>());
         var id = String.valueOf(AccountManagerUtils.getUserID(eup));
 
-        mutableAdsSet.addAll(getDefaultPrefs().getStringSet("whitelisted_filters_groups", mutableAdsSet));
-
+        var mutableAdsSet = new LinkedHashSet<>(getDefaultPrefs().getStringSet(
+                "whitelisted_filters_groups",
+                Collections.emptySet())
+        );
         if (needWhitelist) {
             mutableAdsSet.add(id);
         } else {
@@ -93,10 +99,11 @@ public class NewsfeedHook {
     }
 
     public static void setWhitelistedAd(ExtendedCommunityProfile eup, boolean needWhitelist) {
-        var mutableAdsSet = Collections.synchronizedSet(new LinkedHashSet<String>());
         var id = String.valueOf(AccountManagerUtils.getUserID(eup));
 
-        mutableAdsSet.addAll(getDefaultPrefs().getStringSet("whitelisted_ad_groups", mutableAdsSet));
+        var mutableAdsSet = new LinkedHashSet<>(getDefaultPrefs().getStringSet(
+                "whitelisted_ad_groups",
+                Collections.emptySet()));
 
         if (needWhitelist) {
             mutableAdsSet.add(id);

app/src/main/java/ru/vtosters/lite/music/M3UDownloader.java

@@ -60,7 +60,7 @@ public class M3UDownloader implements ITrackDownloader {
         VKM3UParser parser = new VKM3UParser(payload);
         List<TransportStream> tses = parser.getTransportStreams();
         AtomicInteger progress = new AtomicInteger(0);
-        List<CompletableFuture<Void>> futures = new ArrayList<>();
+        List<CompletableFuture<Void>> futures = new ArrayList<>(tses.size());
 
         var tsesDir = new File(outDir, String.valueOf(track.d));
         tsesDir.mkdirs();

app/src/main/java/ru/vtosters/lite/translators/BaseTranslator.java

@@ -14,7 +14,12 @@ public abstract class BaseTranslator {
     private static final int YANDEX = 0;
     private static final int GOOGLE = 1;
     private static final int DEEPL = 2;
-    private final LruCache<String, String> cache = new LruCache<>(200);
+    private final LruCache<String, String> cache = new LruCache<>(200) {
+        @Override
+        protected String create(@NonNull String text) {
+            return translate(text, getToLanguage());
+        }
+    };
 
     public static String getToLanguage() {
         var lang = preferences.getString("lang_target", "system");
@@ -43,11 +48,8 @@ public abstract class BaseTranslator {
 
     @NonNull
     public final String getTranslation(String text) {
-        var val = cache.get(text);
-        if (val != null)
-            return val;
-        var translation = translate(text, getToLanguage());
-        cache.put(text, translation);
-        return translation;
+        String v = cache.get(text);
+        assert v != null;
+        return v;
     }
 }

app/src/main/java/ru/vtosters/lite/translators/DeepLTranslator.java

@@ -10,7 +10,6 @@ import org.json.JSONObject;
 import java.nio.charset.StandardCharsets;
 import java.util.UUID;
 import java.util.concurrent.ThreadLocalRandom;
-import java.util.concurrent.atomic.AtomicLong;
 import java.util.regex.Pattern;
 
 import okhttp3.MediaType;
@@ -49,14 +48,17 @@ public class DeepLTranslator extends BaseTranslator {
     private static DeepLTranslator instance;
 
     public static DeepLTranslator getInstance() {
-        if (instance == null)
-            instance = new DeepLTranslator();
-        return instance;
+        // Race safe when the new object does not contain the state of the previous one
+        DeepLTranslator translator = instance;
+        if (translator == null) {
+            return instance = new DeepLTranslator();
+        }
+        return translator;
     }
 
     private static Long getTimestamp(int iNumber) {
         var now = System.currentTimeMillis();
-        return Long.valueOf((((long) iNumber) + now) - (now % ((long) iNumber)));
+        return (((long) iNumber) + now) - (now % ((long) iNumber));
     }
 
     @NonNull
@@ -73,16 +75,16 @@ public class DeepLTranslator extends BaseTranslator {
                 i++;
             }
 
-            var id = new AtomicLong(ThreadLocalRandom.current().nextLong(Long.parseLong("10000000000")));
+            var id = ThreadLocalRandom.current().nextLong(1, 10000000000L);
 
             var requestBody = String.format(REQUEST_BODY_FORMAT,
-                    id.incrementAndGet(),
+                    id,
                     text,
                     tl,
                     getTimestamp(i)
             );
 
-            requestBody = (id.get() + 3) % 13 == 0 || (id.get() + 5) % 29 == 0
+            requestBody = (id + 3) % 13 == 0 || (id + 5) % 29 == 0
                     ? requestBody.replace("hod\":\"", "hod\" : \"")
                     : requestBody.replace("hod\":\"", "hod\": \"");
 

app/src/main/java/ru/vtosters/lite/translators/GoogleTranslator.java

@@ -38,9 +38,11 @@ public class GoogleTranslator extends BaseTranslator {
     private static GoogleTranslator instance;
 
     public static GoogleTranslator getInstance() {
-        if (instance == null)
-            instance = new GoogleTranslator();
-        return instance;
+        // Race safe when the new object does not contain the state of the previous one
+        GoogleTranslator translator = instance;
+        if (translator == null)
+            return instance = new GoogleTranslator();
+        return translator;
     }
 
     @NonNull

app/src/main/java/ru/vtosters/lite/translators/YandexTranslator.java

@@ -22,9 +22,11 @@ public class YandexTranslator extends BaseTranslator {
     private static YandexTranslator instance;
 
     public static YandexTranslator getInstance() {
-        if (instance == null)
-            instance = new YandexTranslator();
-        return instance;
+        // Race safe when the new object does not contain the state of the previous one
+        YandexTranslator translator = instance;
+        if (translator == null)
+            return instance = new YandexTranslator();
+        return translator;
     }
 
     @NonNull

app/src/main/java/ru/vtosters/lite/ui/dialogs/Translate.java

@@ -11,21 +11,30 @@ import android.util.Log;
 
 import com.vk.core.dialogs.alert.VkAlertDialog;
 
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
 import ru.vtosters.lite.translators.BaseTranslator;
 import ru.vtosters.lite.utils.AndroidUtils;
 
 public class Translate {
+    private static final Executor ASYNC_EXECUTOR
+            = Executors.newSingleThreadExecutor();
+    private static final Executor MAIN_EXECUTOR
+            = new DelegateExecutor();
+
     public static void showTranslatedText(Context context, String text) {
-        new Thread(() -> {
+        BaseTranslator translator = BaseTranslator.getInstance();
+        if (translator == null) return;
+        ASYNC_EXECUTOR.execute(() -> {
             try {
-                var translation = BaseTranslator.getInstance().getTranslation(text);
-                new Handler(Looper.getMainLooper()).post(() -> {
-                    showDialog(context, translation);
-                });
+                var translation = translator.getTranslation(text);
+                MAIN_EXECUTOR.execute(() -> showDialog(context, translation));
             } catch (Exception e) {
                 Log.e("Translate", e + "");
             }
-        }).start();
+        });
     }
 
     private static void showDialog(Context context, String text) {
@@ -42,4 +51,13 @@ public class Translate {
                 })
                 .show();
     }
+
+    private static class DelegateExecutor implements Executor {
+        private final Handler handler = new Handler(Looper.getMainLooper());
+
+        @Override
+        public void execute(Runnable command) {
+            handler.post(command);
+        }
+    }
 }