Refactor: Migrate bookmark location logic to Kotlin

This commit migrates the bookmark location logic to Kotlin, enhancing code maintainability and readability.

-   Removes the `BookmarkLocationsContentProvider`, `BookmarkLocationsController`, and `BookmarkLocationsDao` Java classes.
-   Creates `BookmarkLocationsDao.kt` and `BookmarkLocationsContentProvider.kt` in Kotlin.
-   Migrates the logic from `BookmarkLocationsFragment.java` to `BookmarkLocationsFragment.kt`.
-   Updates test files to reflect these changes.
-   Addresses associated code review comments.

app/src/main/java/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationsContentProvider.kt

@@ -1,119 +1,126 @@
-package fr.free.nrw.commons.bookmarks.locations;
+package fr.free.nrw.commons.bookmarks.locations
 
-import android.content.ContentValues;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-import android.database.sqlite.SQLiteQueryBuilder;
-// We can get uri using java.Net.Uri, but andoid implimentation is faster (but it's forgiving with handling exceptions though)
-import android.net.Uri;
-import android.text.TextUtils;
+// We can get uri using java.Net.Uri, but android implementation is faster
+// (but it's forgiving with handling exceptions though)
+import android.content.ContentValues
+import android.database.Cursor
+import android.database.sqlite.SQLiteQueryBuilder
+import android.net.Uri
+import fr.free.nrw.commons.BuildConfig
+import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.COLUMN_NAME
+import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.TABLE_NAME
+import fr.free.nrw.commons.data.DBOpenHelper
+import fr.free.nrw.commons.di.CommonsDaggerContentProvider
+import timber.log.Timber
+import javax.inject.Inject
 
-import androidx.annotation.NonNull;
-
-import javax.inject.Inject;
-
-import fr.free.nrw.commons.BuildConfig;
-import fr.free.nrw.commons.data.DBOpenHelper;
-import fr.free.nrw.commons.di.CommonsDaggerContentProvider;
-import timber.log.Timber;
-
-import static fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.COLUMN_NAME;
-import static fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.TABLE_NAME;
 
 /**
  * Handles private storage for Bookmark locations
  */
-public class BookmarkLocationsContentProvider extends CommonsDaggerContentProvider {
+class BookmarkLocationsContentProvider : CommonsDaggerContentProvider() {
 
-    private static final String BASE_PATH = "bookmarksLocations";
-    public static final Uri BASE_URI = Uri.parse("content://" + BuildConfig.BOOKMARK_LOCATIONS_AUTHORITY + "/" + BASE_PATH);
+    companion object {
+        private const val BASE_PATH = "bookmarksLocations"
+        val BASE_URI: Uri =
+            Uri.parse("content://${BuildConfig.BOOKMARK_LOCATIONS_AUTHORITY}/$BASE_PATH")
 
         /**
-     * Append bookmark locations name to the base uri 
+         * Append bookmark locations name to the base URI.
          */
-    public static Uri uriForName(String name) {
-        return Uri.parse(BASE_URI.toString() + "/" + name);
+        fun uriForName(name: String): Uri {
+            return Uri.parse("$BASE_URI/$name")
+        }
     }
 
-    @Inject DBOpenHelper dbOpenHelper;
+    @Inject
+    lateinit var dbOpenHelper: DBOpenHelper
 
-    @Override
-    public String getType(@NonNull Uri uri) {
-        return null;
+    override fun getType(uri: Uri): String? = null
+
+    /**
+     * Queries the SQLite database for the bookmark locations.
+     */
+    override fun query(
+        uri: Uri,
+        projection: Array<String>?,
+        selection: String?,
+        selectionArgs: Array<String>?,
+        sortOrder: String?
+    ): Cursor {
+        val queryBuilder = SQLiteQueryBuilder().apply {
+            tables = TABLE_NAME
+        }
+
+        val db = dbOpenHelper.readableDatabase
+        val cursor = queryBuilder.query(
+            db,
+            projection,
+            selection,
+            selectionArgs,
+            null,
+            null,
+            sortOrder
+        )
+        cursor.setNotificationUri(context?.contentResolver, uri)
+        return cursor
     }
 
     /**
-     * Queries the SQLite database for the bookmark locations
-     * @param uri : contains the uri for bookmark locations
-     * @param projection
-     * @param selection : handles Where
-     * @param selectionArgs : the condition of Where clause
-     * @param sortOrder : ascending or descending
+     * Handles the update query of local SQLite database.
      */
-    @SuppressWarnings("ConstantConditions")
-    @Override
-    public Cursor query(@NonNull Uri uri, String[] projection, String selection,
-                        String[] selectionArgs, String sortOrder) {
-        SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
-        queryBuilder.setTables(TABLE_NAME);
+    override fun update(
+        uri: Uri,
+        contentValues: ContentValues?,
+        selection: String?,
+        selectionArgs: Array<String>?
+    ): Int {
+        val db = dbOpenHelper.writableDatabase
+        val rowsUpdated: Int
 
-        SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
-        Cursor cursor = queryBuilder.query(db, projection, selection, selectionArgs, null, null, sortOrder);
-        cursor.setNotificationUri(getContext().getContentResolver(), uri);
-
-        return cursor;
-    }
-
-    /**
-     * Handles the update query of local SQLite Database 
-     * @param uri : contains the uri for bookmark locations
-     * @param contentValues : new values to be entered to db
-     * @param selection : handles Where
-     * @param selectionArgs : the condition of Where clause
-     */
-    @SuppressWarnings("ConstantConditions")
-    @Override
-    public int update(@NonNull Uri uri, ContentValues contentValues, String selection,
-                      String[] selectionArgs) {
-        SQLiteDatabase sqlDB = dbOpenHelper.getWritableDatabase();
-        int rowsUpdated;
-        if (TextUtils.isEmpty(selection)) {
-            int id = Integer.valueOf(uri.getLastPathSegment());
-            rowsUpdated = sqlDB.update(TABLE_NAME,
+        if (selection.isNullOrEmpty()) {
+            val id = uri.lastPathSegment?.toIntOrNull()
+                ?: throw IllegalArgumentException("Invalid ID in URI")
+            rowsUpdated = db.update(
+                TABLE_NAME,
                 contentValues,
-                    COLUMN_NAME + " = ?",
-                    new String[]{String.valueOf(id)});
+                "$COLUMN_NAME = ?",
+                arrayOf(id.toString())
+            )
         } else {
-            throw new IllegalArgumentException(
-                    "Parameter `selection` should be empty when updating an ID");
+            throw IllegalArgumentException(
+                "Parameter `selection` should be empty when updating an ID"
+            )
         }
-        getContext().getContentResolver().notifyChange(uri, null);
-        return rowsUpdated;
+
+        context?.contentResolver?.notifyChange(uri, null)
+        return rowsUpdated
     }
 
     /**
-     * Handles the insertion of new bookmark locations record to local SQLite Database
+     * Handles the insertion of a new bookmark locations record to the local SQLite database.
      */
-    @SuppressWarnings("ConstantConditions")
-    @Override
-    public Uri insert(@NonNull Uri uri, ContentValues contentValues) {
-        SQLiteDatabase sqlDB = dbOpenHelper.getWritableDatabase();
-        long id = sqlDB.insert(BookmarkLocationsDao.Table.TABLE_NAME, null, contentValues);
-        getContext().getContentResolver().notifyChange(uri, null);
-        return Uri.parse(BASE_URI + "/" + id);
+    override fun insert(uri: Uri, contentValues: ContentValues?): Uri {
+        val db = dbOpenHelper.writableDatabase
+        val id = db.insert(TABLE_NAME, null, contentValues)
+        context?.contentResolver?.notifyChange(uri, null)
+        return Uri.parse("$BASE_URI/$id")
     }
 
-    @SuppressWarnings("ConstantConditions")
-    @Override
-    public int delete(@NonNull Uri uri, String s, String[] strings) {
-        int rows;
-        SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
-        Timber.d("Deleting bookmark name %s", uri.getLastPathSegment());
-        rows = db.delete(TABLE_NAME,
+    /**
+     * Handles the deletion of bookmark locations from the local SQLite database.
+     */
+    override fun delete(uri: Uri, selection: String?, selectionArgs: Array<String>?): Int {
+        val db = dbOpenHelper.readableDatabase
+        Timber.d("Deleting bookmark name %s", uri.lastPathSegment)
+
+        val rows = db.delete(
+            TABLE_NAME,
             "location_name = ?",
-                new String[]{uri.getLastPathSegment()}
-        );
-        getContext().getContentResolver().notifyChange(uri, null);
-        return rows;
+            arrayOf(uri.lastPathSegment)
+        )
+
+        context?.contentResolver?.notifyChange(uri, null)
+        return rows
     }
 }

app/src/main/java/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationsController.kt

@@ -1,26 +1,17 @@
-package fr.free.nrw.commons.bookmarks.locations;
+package fr.free.nrw.commons.bookmarks.locations
 
-import java.util.List;
-
-import javax.inject.Inject;
-import javax.inject.Singleton;
-
-import fr.free.nrw.commons.nearby.Place;
+import fr.free.nrw.commons.nearby.Place
+import javax.inject.Inject
+import javax.inject.Singleton
 
 @Singleton
-public class BookmarkLocationsController {
-
-    @Inject
-    BookmarkLocationsDao bookmarkLocationDao;
-
-    @Inject
-    public BookmarkLocationsController() {}
+class BookmarkLocationsController @Inject constructor(
+    private val bookmarkLocationDao: BookmarkLocationsDao
+) {
 
     /**
-     * Load from DB the bookmarked locations
+     * Load bookmarked locations from the database.
      * @return a list of Place objects.
      */
-    public List<Place> loadFavoritesLocations() {
-        return bookmarkLocationDao.getAllBookmarksLocations();
-    }
+    fun loadFavoritesLocations(): List<Place> = bookmarkLocationDao.getAllBookmarksLocations()
 }

app/src/main/java/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationsDao.kt

@@ -1,311 +1,284 @@
-package fr.free.nrw.commons.bookmarks.locations;
+package fr.free.nrw.commons.bookmarks.locations
 
-import android.annotation.SuppressLint;
-import android.content.ContentProviderClient;
-import android.content.ContentValues;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-import android.database.sqlite.SQLiteException;
-import android.os.RemoteException;
 
-import androidx.annotation.NonNull;
+import android.annotation.SuppressLint
+import android.content.ContentProviderClient
+import android.content.ContentValues
+import android.database.Cursor
+import android.database.sqlite.SQLiteDatabase
+import android.database.sqlite.SQLiteException
+import android.os.RemoteException
+import androidx.annotation.NonNull
+import fr.free.nrw.commons.location.LatLng
+import fr.free.nrw.commons.nearby.Label
+import fr.free.nrw.commons.nearby.NearbyController
+import fr.free.nrw.commons.nearby.Place
+import fr.free.nrw.commons.nearby.Sitelinks
+import timber.log.Timber
+import javax.inject.Inject
+import javax.inject.Named
+import javax.inject.Provider
 
-import fr.free.nrw.commons.nearby.NearbyController;
-import java.util.ArrayList;
-import java.util.List;
 
-import javax.inject.Inject;
-import javax.inject.Named;
-import javax.inject.Provider;
-
-import fr.free.nrw.commons.location.LatLng;
-import fr.free.nrw.commons.nearby.Label;
-import fr.free.nrw.commons.nearby.Place;
-import fr.free.nrw.commons.nearby.Sitelinks;
-import timber.log.Timber;
-
-import static fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsContentProvider.BASE_URI;
-
-public class BookmarkLocationsDao {
-
-    private final Provider<ContentProviderClient> clientProvider;
-
-    @Inject
-    public BookmarkLocationsDao(@Named("bookmarksLocation") Provider<ContentProviderClient> clientProvider) {
-        this.clientProvider = clientProvider;
-    }
+class BookmarkLocationsDao @Inject constructor(
+    @Named("bookmarksLocation") private val clientProvider: Provider<ContentProviderClient>
+) {
 
     /**
-     *  Find all persisted locations bookmarks on database
-     *
+     * Find all persisted location bookmarks in the database
      * @return list of Place
      */
-    @NonNull
-    public List<Place> getAllBookmarksLocations() {
-        List<Place> items = new ArrayList<>();
-        Cursor cursor = null;
-        ContentProviderClient db = clientProvider.get();
+    fun getAllBookmarksLocations(): List<Place> {
+        val items = mutableListOf<Place>()
+        var cursor: Cursor? = null
+        val db = clientProvider.get()
         try {
             cursor = db.query(
                 BookmarkLocationsContentProvider.BASE_URI,
                 Table.ALL_FIELDS,
                 null,
-                new String[]{},
-                null);
-            while (cursor != null && cursor.moveToNext()) {
-                items.add(fromCursor(cursor));
+                emptyArray(),
+                null
+            )
+            cursor?.let {
+                while (it.moveToNext()) {
+                    items.add(fromCursor(it))
                 }
-        } catch (RemoteException e) {
-            throw new RuntimeException(e);
+            }
+        } catch (e: RemoteException) {
+            throw RuntimeException(e)
         } finally {
-            if (cursor != null) {
-                cursor.close();
+            cursor?.close()
+            db.release()
         }
-            db.release();
-        }
-        return items;
+        return items
     }
 
     /**
      * Look for a place in bookmarks table in order to insert or delete it
-     *
      * @param bookmarkLocation : Place object
-     * @return is Place now fav ?
+     * @return boolean : is Place now fav ?
      */
-    public boolean updateBookmarkLocation(Place bookmarkLocation) {
-        boolean bookmarkExists = findBookmarkLocation(bookmarkLocation);
+    fun updateBookmarkLocation(bookmarkLocation: Place): Boolean {
+        val bookmarkExists = findBookmarkLocation(bookmarkLocation)
         if (bookmarkExists) {
-            deleteBookmarkLocation(bookmarkLocation);
-            NearbyController.updateMarkerLabelListBookmark(bookmarkLocation, false);
+            deleteBookmarkLocation(bookmarkLocation)
+            NearbyController.updateMarkerLabelListBookmark(bookmarkLocation, false)
         } else {
-            addBookmarkLocation(bookmarkLocation);
-            NearbyController.updateMarkerLabelListBookmark(bookmarkLocation, true);
+            addBookmarkLocation(bookmarkLocation)
+            NearbyController.updateMarkerLabelListBookmark(bookmarkLocation, true)
         }
-        return !bookmarkExists;
+        return !bookmarkExists
     }
 
     /**
      * Add a Place to bookmarks table
-     *
      * @param bookmarkLocation : Place to add
      */
-    private void addBookmarkLocation(Place bookmarkLocation) {
-        ContentProviderClient db = clientProvider.get();
+    private fun addBookmarkLocation(bookmarkLocation: Place) {
+        val db = clientProvider.get()
         try {
-            db.insert(BASE_URI, toContentValues(bookmarkLocation));
-        } catch (RemoteException e) {
-            throw new RuntimeException(e);
+            db.insert(BookmarkLocationsContentProvider.BASE_URI, toContentValues(bookmarkLocation))
+        } catch (e: RemoteException) {
+            throw RuntimeException(e)
         } finally {
-            db.release();
+            db.release()
         }
     }
 
     /**
      * Delete a Place from bookmarks table
-     *
      * @param bookmarkLocation : Place to delete
      */
-    private void deleteBookmarkLocation(Place bookmarkLocation) {
-        ContentProviderClient db = clientProvider.get();
+    private fun deleteBookmarkLocation(bookmarkLocation: Place) {
+        val db = clientProvider.get()
         try {
-            db.delete(BookmarkLocationsContentProvider.uriForName(bookmarkLocation.name), null, null);
-        } catch (RemoteException e) {
-            throw new RuntimeException(e);
+            db.delete(
+                BookmarkLocationsContentProvider.uriForName(bookmarkLocation.name),
+                null,
+                null
+            )
+        } catch (e: RemoteException) {
+            throw RuntimeException(e)
         } finally {
-            db.release();
+            db.release()
         }
     }
 
     /**
      * Find a Place from database based on its name
-     *
      * @param bookmarkLocation : Place to find
      * @return boolean : is Place in database ?
      */
-    public boolean findBookmarkLocation(Place bookmarkLocation) {
-        Cursor cursor = null;
-        ContentProviderClient db = clientProvider.get();
+    fun findBookmarkLocation(bookmarkLocation: Place): Boolean {
+        var cursor: Cursor? = null
+        val db = clientProvider.get()
         try {
             cursor = db.query(
                 BookmarkLocationsContentProvider.BASE_URI,
                 Table.ALL_FIELDS,
-                Table.COLUMN_NAME + "=?",
-                new String[]{bookmarkLocation.name},
-                null);
-            if (cursor != null && cursor.moveToFirst()) {
-                return true;
-            }
-        } catch (RemoteException e) {
-            // This feels lazy, but to hell with checked exceptions. :)
-            throw new RuntimeException(e);
+                "${Table.COLUMN_NAME}=?",
+                arrayOf(bookmarkLocation.name),
+                null
+            )
+            return cursor?.moveToFirst() == true
+        } catch (e: RemoteException) {
+            throw RuntimeException(e)
         } finally {
-            if (cursor != null) {
-                cursor.close();
+            cursor?.close()
+            db.release()
         }
-            db.release();
-        }
-        return false;
     }
 
     @SuppressLint("Range")
     @NonNull
-    Place fromCursor(final Cursor cursor) {
-        final LatLng location = new LatLng(cursor.getDouble(cursor.getColumnIndex(Table.COLUMN_LAT)),
-            cursor.getDouble(cursor.getColumnIndex(Table.COLUMN_LONG)), 1F);
+    fun fromCursor(cursor: Cursor): Place {
+        val location = LatLng(
+            cursor.getDouble(cursor.getColumnIndex(Table.COLUMN_LAT)),
+            cursor.getDouble(cursor.getColumnIndex(Table.COLUMN_LONG)),
+            1F
+        )
 
-        final Sitelinks.Builder builder = new Sitelinks.Builder();
-        builder.setWikipediaLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_WIKIPEDIA_LINK)));
-        builder.setWikidataLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_WIKIDATA_LINK)));
-        builder.setCommonsLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_COMMONS_LINK)));
+        val builder = Sitelinks.Builder().apply {
+            setWikipediaLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_WIKIPEDIA_LINK)))
+            setWikidataLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_WIKIDATA_LINK)))
+            setCommonsLink(cursor.getString(cursor.getColumnIndex(Table.COLUMN_COMMONS_LINK)))
+        }
 
-        return new Place(
+        return Place(
             cursor.getString(cursor.getColumnIndex(Table.COLUMN_LANGUAGE)),
             cursor.getString(cursor.getColumnIndex(Table.COLUMN_NAME)),
-            Label.fromText((cursor.getString(cursor.getColumnIndex(Table.COLUMN_LABEL_TEXT)))),
+            Label.fromText(cursor.getString(cursor.getColumnIndex(Table.COLUMN_LABEL_TEXT))),
             cursor.getString(cursor.getColumnIndex(Table.COLUMN_DESCRIPTION)),
             location,
             cursor.getString(cursor.getColumnIndex(Table.COLUMN_CATEGORY)),
             builder.build(),
             cursor.getString(cursor.getColumnIndex(Table.COLUMN_PIC)),
-            Boolean.parseBoolean(cursor.getString(cursor.getColumnIndex(Table.COLUMN_EXISTS)))
-        );
+            cursor.getString(cursor.getColumnIndex(Table.COLUMN_EXISTS))?.toBoolean() ?: false
+        )
     }
 
-    private ContentValues toContentValues(Place bookmarkLocation) {
-        ContentValues cv = new ContentValues();
-        cv.put(BookmarkLocationsDao.Table.COLUMN_NAME, bookmarkLocation.getName());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_LANGUAGE, bookmarkLocation.getLanguage());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_DESCRIPTION, bookmarkLocation.getLongDescription());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_CATEGORY, bookmarkLocation.getCategory());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_LABEL_TEXT, bookmarkLocation.getLabel()!=null ? bookmarkLocation.getLabel().getText() : "");
-        cv.put(BookmarkLocationsDao.Table.COLUMN_LABEL_ICON, bookmarkLocation.getLabel()!=null ? bookmarkLocation.getLabel().getIcon() : null);
-        cv.put(BookmarkLocationsDao.Table.COLUMN_WIKIPEDIA_LINK, bookmarkLocation.siteLinks.getWikipediaLink().toString());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_WIKIDATA_LINK, bookmarkLocation.siteLinks.getWikidataLink().toString());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_COMMONS_LINK, bookmarkLocation.siteLinks.getCommonsLink().toString());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_LAT, bookmarkLocation.location.getLatitude());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_LONG, bookmarkLocation.location.getLongitude());
-        cv.put(BookmarkLocationsDao.Table.COLUMN_PIC, bookmarkLocation.pic);
-        cv.put(BookmarkLocationsDao.Table.COLUMN_EXISTS, bookmarkLocation.exists.toString());
-        return cv;
+    private fun toContentValues(bookmarkLocation: Place): ContentValues {
+        return ContentValues().apply {
+            put(Table.COLUMN_NAME, bookmarkLocation.name)
+            put(Table.COLUMN_LANGUAGE, bookmarkLocation.language)
+            put(Table.COLUMN_DESCRIPTION, bookmarkLocation.longDescription)
+            put(Table.COLUMN_CATEGORY, bookmarkLocation.category)
+            put(Table.COLUMN_LABEL_TEXT, bookmarkLocation.label?.text ?: "")
+            put(Table.COLUMN_LABEL_ICON, bookmarkLocation.label?.icon)
+            put(Table.COLUMN_WIKIPEDIA_LINK, bookmarkLocation.siteLinks.wikipediaLink.toString())
+            put(Table.COLUMN_WIKIDATA_LINK, bookmarkLocation.siteLinks.wikidataLink.toString())
+            put(Table.COLUMN_COMMONS_LINK, bookmarkLocation.siteLinks.commonsLink.toString())
+            put(Table.COLUMN_LAT, bookmarkLocation.location.latitude)
+            put(Table.COLUMN_LONG, bookmarkLocation.location.longitude)
+            put(Table.COLUMN_PIC, bookmarkLocation.pic)
+            put(Table.COLUMN_EXISTS, bookmarkLocation.exists.toString())
+        }
     }
 
-    public static class Table {
-        public static final String TABLE_NAME = "bookmarksLocations";
+    object Table {
+        const val TABLE_NAME = "bookmarksLocations"
 
-        static final String COLUMN_NAME = "location_name";
-        static final String COLUMN_LANGUAGE = "location_language";
-        static final String COLUMN_DESCRIPTION = "location_description";
-        static final String COLUMN_LAT = "location_lat";
-        static final String COLUMN_LONG = "location_long";
-        static final String COLUMN_CATEGORY = "location_category";
-        static final String COLUMN_LABEL_TEXT = "location_label_text";
-        static final String COLUMN_LABEL_ICON = "location_label_icon";
-        static final String COLUMN_IMAGE_URL = "location_image_url";
-        static final String COLUMN_WIKIPEDIA_LINK = "location_wikipedia_link";
-        static final String COLUMN_WIKIDATA_LINK = "location_wikidata_link";
-        static final String COLUMN_COMMONS_LINK = "location_commons_link";
-        static final String COLUMN_PIC = "location_pic";
-        static final String COLUMN_EXISTS = "location_exists";
+        const val COLUMN_NAME = "location_name"
+        const val COLUMN_LANGUAGE = "location_language"
+        const val COLUMN_DESCRIPTION = "location_description"
+        const val COLUMN_LAT = "location_lat"
+        const val COLUMN_LONG = "location_long"
+        const val COLUMN_CATEGORY = "location_category"
+        const val COLUMN_LABEL_TEXT = "location_label_text"
+        const val COLUMN_LABEL_ICON = "location_label_icon"
+        const val COLUMN_IMAGE_URL = "location_image_url"
+        const val COLUMN_WIKIPEDIA_LINK = "location_wikipedia_link"
+        const val COLUMN_WIKIDATA_LINK = "location_wikidata_link"
+        const val COLUMN_COMMONS_LINK = "location_commons_link"
+        const val COLUMN_PIC = "location_pic"
+        const val COLUMN_EXISTS = "location_exists"
 
         // NOTE! KEEP IN SAME ORDER AS THEY ARE DEFINED UP THERE. HELPS HARD CODE COLUMN INDICES.
-        public static final String[] ALL_FIELDS = {
-            COLUMN_NAME,
-            COLUMN_LANGUAGE,
-            COLUMN_DESCRIPTION,
-            COLUMN_CATEGORY,
-            COLUMN_LABEL_TEXT,
-            COLUMN_LABEL_ICON,
-            COLUMN_LAT,
-            COLUMN_LONG,
-            COLUMN_IMAGE_URL,
-            COLUMN_WIKIPEDIA_LINK,
-            COLUMN_WIKIDATA_LINK,
-            COLUMN_COMMONS_LINK,
-            COLUMN_PIC,
-            COLUMN_EXISTS,
-        };
+        val ALL_FIELDS = arrayOf(
+            COLUMN_NAME, COLUMN_LANGUAGE, COLUMN_DESCRIPTION, COLUMN_CATEGORY, COLUMN_LABEL_TEXT, COLUMN_LABEL_ICON,
+            COLUMN_LAT, COLUMN_LONG, COLUMN_IMAGE_URL, COLUMN_WIKIPEDIA_LINK, COLUMN_WIKIDATA_LINK, COLUMN_COMMONS_LINK,
+            COLUMN_PIC, COLUMN_EXISTS
+        )
 
-        static final String DROP_TABLE_STATEMENT = "DROP TABLE IF EXISTS " + TABLE_NAME;
+        const val DROP_TABLE_STATEMENT = "DROP TABLE IF EXISTS $TABLE_NAME"
 
-        static final String CREATE_TABLE_STATEMENT = "CREATE TABLE " + TABLE_NAME + " ("
-            + COLUMN_NAME + " STRING PRIMARY KEY,"
-            + COLUMN_LANGUAGE + " STRING,"
-            + COLUMN_DESCRIPTION + " STRING,"
-            + COLUMN_CATEGORY + " STRING,"
-            + COLUMN_LABEL_TEXT + " STRING,"
-            + COLUMN_LABEL_ICON + " INTEGER,"
-            + COLUMN_LAT + " DOUBLE,"
-            + COLUMN_LONG + " DOUBLE,"
-            + COLUMN_IMAGE_URL + " STRING,"
-            + COLUMN_WIKIPEDIA_LINK + " STRING,"
-            + COLUMN_WIKIDATA_LINK + " STRING,"
-            + COLUMN_COMMONS_LINK + " STRING,"
-            + COLUMN_PIC + " STRING,"
-            + COLUMN_EXISTS + " STRING"
-            + ");";
+        const val CREATE_TABLE_STATEMENT = """
+            CREATE TABLE $TABLE_NAME (
+                $COLUMN_NAME STRING PRIMARY KEY,
+                $COLUMN_LANGUAGE STRING,
+                $COLUMN_DESCRIPTION STRING,
+                $COLUMN_CATEGORY STRING,
+                $COLUMN_LABEL_TEXT STRING,
+                $COLUMN_LABEL_ICON INTEGER,
+                $COLUMN_LAT DOUBLE,
+                $COLUMN_LONG DOUBLE,
+                $COLUMN_IMAGE_URL STRING,
+                $COLUMN_WIKIPEDIA_LINK STRING,
+                $COLUMN_WIKIDATA_LINK STRING,
+                $COLUMN_COMMONS_LINK STRING,
+                $COLUMN_PIC STRING,
+                $COLUMN_EXISTS STRING
+            );
+        """
 
-        public static void onCreate(SQLiteDatabase db) {
-            db.execSQL(CREATE_TABLE_STATEMENT);
+        fun onCreate(db: SQLiteDatabase) {
+            db.execSQL(CREATE_TABLE_STATEMENT)
         }
 
-        public static void onDelete(SQLiteDatabase db) {
-            db.execSQL(DROP_TABLE_STATEMENT);
-            onCreate(db);
+        fun onDelete(db: SQLiteDatabase) {
+            db.execSQL(DROP_TABLE_STATEMENT)
+            onCreate(db)
         }
 
-        public static void onUpdate(final SQLiteDatabase db, int from, final int to) {
-            Timber.d("bookmarksLocations db is updated from:"+from+", to:"+to);
+        @SuppressLint("SQLiteString")
+        fun onUpdate(db: SQLiteDatabase, from: Int, to: Int) {
+            Timber.d("bookmarksLocations db is updated from:$from, to:$to")
+            var currFrom = from
+
             if (from == to) {
-                return;
+                return
             }
             if (from < 7) {
-                // doesn't exist yet
-                from++;
-                onUpdate(db, from, to);
-                return;
+                onUpdate(db, ++currFrom, to)
+                return
             }
             if (from == 7) {
-                // table added in version 8
-                onCreate(db);
-                from++;
-                onUpdate(db, from, to);
-                return;
+                onCreate(db)
+                onUpdate(db, ++currFrom, to)
+                return
             }
             if (from < 10) {
-                from++;
-                onUpdate(db, from, to);
-                return;
+                onUpdate(db, ++currFrom, to)
+                return
             }
             if (from == 10) {
-                //This is safe, and can be called clean, as we/I do not remember the appropriate version for this
-                //We are anyways switching to room, these things won't be necessary then
                 try {
-                    db.execSQL("ALTER TABLE bookmarksLocations ADD COLUMN location_pic STRING;");
-                }catch (SQLiteException exception){
-                    Timber.e(exception);//
+                    db.execSQL("ALTER TABLE $TABLE_NAME ADD COLUMN location_pic STRING;")
+                } catch (exception: SQLiteException) {
+                    Timber.e(exception)
                 }
-                return;
+                return
             }
             if (from >= 12) {
                 try {
-                    db.execSQL(
-                        "ALTER TABLE bookmarksLocations ADD COLUMN location_destroyed STRING;");
-                } catch (SQLiteException exception) {
-                    Timber.e(exception);
+                    db.execSQL("ALTER TABLE $TABLE_NAME ADD COLUMN location_destroyed STRING;")
+                } catch (exception: SQLiteException) {
+                    Timber.e(exception)
                 }
             }
             if (from >= 13) {
                 try {
-                    db.execSQL("ALTER TABLE bookmarksLocations ADD COLUMN location_language STRING;");
-                } catch (SQLiteException exception){
-                    Timber.e(exception);
+                    db.execSQL("ALTER TABLE $TABLE_NAME ADD COLUMN location_language STRING;")
+                } catch (exception: SQLiteException) {
+                    Timber.e(exception)
                 }
             }
             if (from >= 14) {
                 try {
-                    db.execSQL("ALTER TABLE bookmarksLocations ADD COLUMN location_exists STRING;");
-                } catch (SQLiteException exception){
-                    Timber.e(exception);
+                    db.execSQL("ALTER TABLE $TABLE_NAME ADD COLUMN location_exists STRING;")
+                } catch (exception: SQLiteException) {
+                    Timber.e(exception)
                 }
             }
         }

app/src/main/java/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationsFragment.kt

@@ -1,137 +1,145 @@
-package fr.free.nrw.commons.bookmarks.locations;
+package fr.free.nrw.commons.bookmarks.locations
 
-import android.Manifest.permission;
-import android.content.Intent;
-import android.os.Bundle;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import androidx.activity.result.ActivityResultCallback;
-import androidx.activity.result.ActivityResultLauncher;
-import androidx.activity.result.contract.ActivityResultContracts;
-import androidx.activity.result.contract.ActivityResultContracts.StartActivityForResult;
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.recyclerview.widget.LinearLayoutManager;
-import dagger.android.support.DaggerFragment;
-import fr.free.nrw.commons.R;
-import fr.free.nrw.commons.contributions.ContributionController;
-import fr.free.nrw.commons.databinding.FragmentBookmarksLocationsBinding;
-import fr.free.nrw.commons.nearby.Place;
-import fr.free.nrw.commons.nearby.fragments.CommonPlaceClickActions;
-import fr.free.nrw.commons.nearby.fragments.PlaceAdapter;
-import java.util.List;
-import java.util.Map;
-import javax.inject.Inject;
-import kotlin.Unit;
+import android.Manifest.permission
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContracts.RequestMultiplePermissions
+import androidx.activity.result.contract.ActivityResultContracts.StartActivityForResult
+import androidx.recyclerview.widget.LinearLayoutManager
+import dagger.android.support.DaggerFragment
+import fr.free.nrw.commons.R
+import fr.free.nrw.commons.contributions.ContributionController
+import fr.free.nrw.commons.databinding.FragmentBookmarksLocationsBinding
+import fr.free.nrw.commons.filepicker.FilePicker
+import fr.free.nrw.commons.nearby.fragments.CommonPlaceClickActions
+import fr.free.nrw.commons.nearby.fragments.PlaceAdapter
+import javax.inject.Inject
 
-public class BookmarkLocationsFragment extends DaggerFragment {
 
-    public FragmentBookmarksLocationsBinding binding;
+class BookmarkLocationsFragment : DaggerFragment() {
 
-    @Inject BookmarkLocationsController controller;
-    @Inject ContributionController contributionController;
-    @Inject BookmarkLocationsDao bookmarkLocationDao;
-    @Inject CommonPlaceClickActions commonPlaceClickActions;
-    private PlaceAdapter adapter;
+    private var binding: FragmentBookmarksLocationsBinding? = null
 
-    private final ActivityResultLauncher<Intent> cameraPickLauncherForResult =
-        registerForActivityResult(new StartActivityForResult(),
-        result -> {
-            contributionController.handleActivityResultWithCallback(requireActivity(), callbacks -> {
-                contributionController.onPictureReturnedFromCamera(result, requireActivity(), callbacks);
-            });
-        });
+    @Inject lateinit var controller: BookmarkLocationsController
+    @Inject lateinit var contributionController: ContributionController
+    @Inject lateinit var bookmarkLocationDao: BookmarkLocationsDao
+    @Inject lateinit var commonPlaceClickActions: CommonPlaceClickActions
 
-      private final ActivityResultLauncher<Intent> galleryPickLauncherForResult =
-          registerForActivityResult(new StartActivityForResult(),
-        result -> {
-              contributionController.handleActivityResultWithCallback(requireActivity(), callbacks -> {
-                contributionController.onPictureReturnedFromGallery(result, requireActivity(), callbacks);
-            });
-        });
+    private lateinit var inAppCameraLocationPermissionLauncher:
+            ActivityResultLauncher<Array<String>>
+    private lateinit var adapter: PlaceAdapter
 
-    private ActivityResultLauncher<String[]> inAppCameraLocationPermissionLauncher = registerForActivityResult(new ActivityResultContracts.RequestMultiplePermissions(), new ActivityResultCallback<Map<String, Boolean>>() {
-        @Override
-        public void onActivityResult(Map<String, Boolean> result) {
-            boolean areAllGranted = true;
-            for(final boolean b : result.values()) {
-                areAllGranted = areAllGranted && b;
+    private val cameraPickLauncherForResult =
+        registerForActivityResult(StartActivityForResult()) { result ->
+            contributionController.handleActivityResultWithCallback(
+                requireActivity(),
+                object: FilePicker.HandleActivityResult {
+                    override fun onHandleActivityResult(callbacks: FilePicker.Callbacks) {
+                        contributionController.onPictureReturnedFromCamera(
+                            result,
+                            requireActivity(),
+                            callbacks
+                        )
                     }
+                }
+            )
+        }
+
+    private val galleryPickLauncherForResult =
+        registerForActivityResult(StartActivityForResult()) { result ->
+            contributionController.handleActivityResultWithCallback(
+                requireActivity(),
+                object: FilePicker.HandleActivityResult {
+                    override fun onHandleActivityResult(callbacks: FilePicker.Callbacks) {
+                        contributionController.onPictureReturnedFromGallery(
+                            result,
+                            requireActivity(),
+                            callbacks
+                        )
+                    }
+                }
+            )
+        }
+
+    companion object {
+        fun newInstance(): BookmarkLocationsFragment {
+            return BookmarkLocationsFragment()
+        }
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        binding = FragmentBookmarksLocationsBinding.inflate(inflater, container, false)
+        return binding?.root
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        binding?.loadingImagesProgressBar?.visibility = View.VISIBLE
+        binding?.listView?.layoutManager = LinearLayoutManager(context)
+
+        inAppCameraLocationPermissionLauncher =
+            registerForActivityResult(RequestMultiplePermissions()) { result ->
+                val areAllGranted = result.values.all { it }
 
                 if (areAllGranted) {
-                contributionController.locationPermissionCallback.onLocationPermissionGranted();
+                    contributionController.locationPermissionCallback.onLocationPermissionGranted()
                 } else {
                     if (shouldShowRequestPermissionRationale(permission.ACCESS_FINE_LOCATION)) {
-                    contributionController.handleShowRationaleFlowCameraLocation(getActivity(), inAppCameraLocationPermissionLauncher, cameraPickLauncherForResult);
+                        contributionController.handleShowRationaleFlowCameraLocation(
+                            activity,
+                            inAppCameraLocationPermissionLauncher,
+                            cameraPickLauncherForResult
+                        )
                     } else {
-                    contributionController.locationPermissionCallback.onLocationPermissionDenied(getActivity().getString(R.string.in_app_camera_location_permission_denied));
+                        contributionController.locationPermissionCallback
+                            .onLocationPermissionDenied(
+                                getString(R.string.in_app_camera_location_permission_denied)
+                            )
                     }
                 }
             }
-    });
-
-    /**
-     * Create an instance of the fragment with the right bundle parameters
-     * @return an instance of the fragment
-     */
-    public static BookmarkLocationsFragment newInstance() {
-        return new BookmarkLocationsFragment();
-    }
 
-    @Override
-    public View onCreateView(
-            @NonNull LayoutInflater inflater,
-            ViewGroup container,
-            Bundle savedInstanceState
-    ) {
-        binding = FragmentBookmarksLocationsBinding.inflate(inflater, container, false);
-        return binding.getRoot();
-    }
-
-    @Override
-    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
-        super.onViewCreated(view, savedInstanceState);
-        binding.loadingImagesProgressBar.setVisibility(View.VISIBLE);
-        binding.listView.setLayoutManager(new LinearLayoutManager(getContext()));
-        adapter = new PlaceAdapter(bookmarkLocationDao,
-            place -> Unit.INSTANCE,
-            (place, isBookmarked) -> {
-                adapter.remove(place);
-                return Unit.INSTANCE;
+        adapter = PlaceAdapter(
+            bookmarkLocationDao,
+            { },
+            { place, _ ->
+                adapter.remove(place)
             },
             commonPlaceClickActions,
             inAppCameraLocationPermissionLauncher,
             galleryPickLauncherForResult,
             cameraPickLauncherForResult
-        );
-        binding.listView.setAdapter(adapter);
+        )
+        binding?.listView?.adapter = adapter
     }
 
-    @Override
-    public void onResume() {
-        super.onResume();
-        initList();
+    override fun onResume() {
+        super.onResume()
+        initList()
     }
 
-    /**
-     * Initialize the recycler view with bookmarked locations
-     */
-    private void initList() {
-        List<Place> places = controller.loadFavoritesLocations();
-        adapter.setItems(places);
-        binding.loadingImagesProgressBar.setVisibility(View.GONE);
-        if (places.size() <= 0) {
-            binding.statusMessage.setText(R.string.bookmark_empty);
-            binding.statusMessage.setVisibility(View.VISIBLE);
+    private fun initList() {
+        val places = controller.loadFavoritesLocations()
+        adapter.items = places
+        binding?.loadingImagesProgressBar?.visibility = View.GONE
+        if (places.isEmpty()) {
+            binding?.statusMessage?.text = getString(R.string.bookmark_empty)
+            binding?.statusMessage?.visibility = View.VISIBLE
         } else {
-            binding.statusMessage.setVisibility(View.GONE);
+            binding?.statusMessage?.visibility = View.GONE
         }
     }
 
-    @Override
-    public void onDestroy() {
-        super.onDestroy();
-        binding = null;
+    override fun onDestroy() {
+        super.onDestroy()
+        // Make sure to null out the binding to avoid memory leaks
+        binding = null
     }
 }

app/src/test/kotlin/fr/free/nrw/commons/bookmarks/locations/BookMarkLocationDaoTest.kt

@@ -18,7 +18,6 @@ import com.nhaarman.mockitokotlin2.mock
 import com.nhaarman.mockitokotlin2.verify
 import com.nhaarman.mockitokotlin2.whenever
 import fr.free.nrw.commons.TestCommonsApplication
-import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsContentProvider.BASE_URI
 import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.COLUMN_CATEGORY
 import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.COLUMN_COMMONS_LINK
 import fr.free.nrw.commons.bookmarks.locations.BookmarkLocationsDao.Table.COLUMN_DESCRIPTION
@@ -149,7 +148,7 @@ class BookMarkLocationDaoTest {
     fun getAllLocationBookmarks() {
         whenever(client.query(any(), any(), anyOrNull(), any(), anyOrNull())).thenReturn(createCursor(14))
 
-        var result = testObject.allBookmarksLocations
+        var result = testObject.getAllBookmarksLocations()
 
         assertEquals(14, result.size)
     }
@@ -157,19 +156,19 @@ class BookMarkLocationDaoTest {
     @Test(expected = RuntimeException::class)
     fun getAllLocationBookmarksTranslatesExceptions() {
         whenever(client.query(any(), any(), anyOrNull(), any(), anyOrNull())).thenThrow(RemoteException(""))
-        testObject.allBookmarksLocations
+        testObject.getAllBookmarksLocations()
     }
 
     @Test
     fun getAllLocationBookmarksReturnsEmptyList_emptyCursor() {
         whenever(client.query(any(), any(), anyOrNull(), any(), anyOrNull())).thenReturn(createCursor(0))
-        assertTrue(testObject.allBookmarksLocations.isEmpty())
+        assertTrue(testObject.getAllBookmarksLocations().isEmpty())
     }
 
     @Test
     fun getAllLocationBookmarksReturnsEmptyList_nullCursor() {
         whenever(client.query(any(), any(), anyOrNull(), any(), anyOrNull())).thenReturn(null)
-        assertTrue(testObject.allBookmarksLocations.isEmpty())
+        assertTrue(testObject.getAllBookmarksLocations().isEmpty())
     }
 
     @Test
@@ -178,7 +177,7 @@ class BookMarkLocationDaoTest {
         whenever(client.query(any(), any(), anyOrNull(), any(), anyOrNull())).thenReturn(mockCursor)
         whenever(mockCursor.moveToFirst()).thenReturn(false)
 
-        testObject.allBookmarksLocations
+        testObject.getAllBookmarksLocations()
 
         verify(mockCursor).close()
     }
@@ -189,7 +188,7 @@ class BookMarkLocationDaoTest {
         whenever(client.query(any(), any(), any(), any(), anyOrNull())).thenReturn(null)
 
         assertTrue(testObject.updateBookmarkLocation(examplePlaceBookmark))
-        verify(client).insert(eq(BASE_URI), captor.capture())
+        verify(client).insert(eq(BookmarkLocationsContentProvider.BASE_URI), captor.capture())
         captor.firstValue.let { cv ->
             assertEquals(13, cv.size())
             assertEquals(examplePlaceBookmark.name, cv.getAsString(COLUMN_NAME))

app/src/test/kotlin/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationControllerTest.kt

@@ -20,7 +20,7 @@ class BookmarkLocationControllerTest {
     @Before
     fun setup() {
         MockitoAnnotations.initMocks(this)
-        whenever(bookmarkDao!!.allBookmarksLocations)
+        whenever(bookmarkDao!!.getAllBookmarksLocations())
             .thenReturn(mockBookmarkList)
     }
 

app/src/test/kotlin/fr/free/nrw/commons/nearby/NearbyParentFragmentPresenterTest.kt

@@ -463,7 +463,7 @@ class NearbyParentFragmentPresenterTest {
         nearbyPlacesInfo.searchLatLng = latestLocation
         nearbyPlacesInfo.placeList = emptyList<Place>()
 
-        whenever(bookmarkLocationsDao.allBookmarksLocations).thenReturn(Collections.emptyList())
+        whenever(bookmarkLocationsDao.getAllBookmarksLocations()).thenReturn(Collections.emptyList())
         nearbyPresenter.updateMapMarkers(nearbyPlacesInfo.placeList, latestLocation, null)
         Mockito.verify(nearbyParentFragmentView).setProgressBarVisibility(false)
     }