Get rid of other singletons

app/src/main/java/fr/free/nrw/commons/CommonsApplication.java

@@ -30,6 +30,7 @@ import fr.free.nrw.commons.contributions.Contribution;
 import fr.free.nrw.commons.data.DBOpenHelper;
 import fr.free.nrw.commons.modifications.ModifierSequence;
 import fr.free.nrw.commons.auth.AccountUtil;
+import fr.free.nrw.commons.nearby.NearbyPlaces;
 
 import org.acra.ACRA;
 import org.acra.ReportingInteractionMode;
@@ -85,6 +86,8 @@ public class CommonsApplication extends Application {
     private MWApi api = null;
     private CacheController cacheData = null;
     private RequestQueue volleyQueue = null;
+    private DBOpenHelper dbOpenHelper = null;
+    private NearbyPlaces nearbyPlaces = null;
 
     /**
      * This should not be called by ANY application code (other than the magic Android glue)
@@ -146,6 +149,20 @@ public class CommonsApplication extends Application {
         return volleyQueue;
     }
 
+    public synchronized DBOpenHelper getDBOpenHelper() {
+        if(dbOpenHelper == null) {
+            dbOpenHelper = new DBOpenHelper(this);
+        }
+        return dbOpenHelper;
+    }
+
+    public synchronized NearbyPlaces getNearbyPlaces() {
+        if (nearbyPlaces == null) {
+            nearbyPlaces = new NearbyPlaces();
+        }
+        return nearbyPlaces;
+    }
+
     @Override
     public void onCreate() {
         super.onCreate();

app/src/main/java/fr/free/nrw/commons/category/CategoryContentProvider.java

@@ -9,6 +9,7 @@ import android.database.sqlite.SQLiteQueryBuilder;
 import android.net.Uri;
 import android.text.TextUtils;
 
+import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.data.DBOpenHelper;
 import timber.log.Timber;
 
@@ -36,7 +37,7 @@ public class CategoryContentProvider extends ContentProvider {
     private DBOpenHelper dbOpenHelper;
     @Override
     public boolean onCreate() {
-        dbOpenHelper = DBOpenHelper.getInstance(getContext());
+        dbOpenHelper = CommonsApplication.getInstance().getDBOpenHelper();
         return false;
     }
 

app/src/main/java/fr/free/nrw/commons/contributions/ContributionsContentProvider.java

@@ -9,6 +9,7 @@ import android.database.sqlite.SQLiteQueryBuilder;
 import android.net.Uri;
 import android.text.TextUtils;
 
+import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.data.DBOpenHelper;
 import timber.log.Timber;
 
@@ -35,7 +36,7 @@ public class ContributionsContentProvider extends ContentProvider{
     private DBOpenHelper dbOpenHelper;
     @Override
     public boolean onCreate() {
-        dbOpenHelper = DBOpenHelper.getInstance(getContext());
+        dbOpenHelper = CommonsApplication.getInstance().getDBOpenHelper();
         return false;
     }
 

app/src/main/java/fr/free/nrw/commons/data/DBOpenHelper.java

@@ -12,16 +12,11 @@ public class DBOpenHelper  extends SQLiteOpenHelper{
 
     private static final String DATABASE_NAME = "commons.db";
     private static final int DATABASE_VERSION = 6;
-    private static DBOpenHelper singleton = null;
 
-    public static synchronized DBOpenHelper getInstance(Context context) {
+    /**
-        if ( singleton == null ) {
+     * Do not use, please call CommonsApplication.getDBOpenHelper()
-            singleton = new DBOpenHelper(context);
+     */
-        }
+    public DBOpenHelper(Context context) {
-        return singleton;
-    }
-
-    private DBOpenHelper(Context context) {
         super(context, DATABASE_NAME, null, DATABASE_VERSION);
     }
 

app/src/main/java/fr/free/nrw/commons/modifications/ModificationsContentProvider.java

@@ -9,6 +9,7 @@ import android.database.sqlite.SQLiteQueryBuilder;
 import android.net.Uri;
 import android.text.TextUtils;
 
+import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.data.DBOpenHelper;
 import timber.log.Timber;
 
@@ -35,7 +36,7 @@ public class ModificationsContentProvider extends ContentProvider{
     private DBOpenHelper dbOpenHelper;
     @Override
     public boolean onCreate() {
-        dbOpenHelper = DBOpenHelper.getInstance(getContext());
+        dbOpenHelper = CommonsApplication.getInstance().getDBOpenHelper();
         return false;
     }
 

app/src/main/java/fr/free/nrw/commons/nearby/NearbyController.java

@@ -15,6 +15,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
+import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.location.LatLng;
 import timber.log.Timber;
@@ -37,13 +38,14 @@ public class NearbyController {
         if (curLatLng == null) {
             return Collections.emptyList();
         }
+        NearbyPlaces nearbyPlaces = CommonsApplication.getInstance().getNearbyPlaces();
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
         List<Place> places = prefs.getBoolean("useWikidata", true)
-                ? NearbyPlaces.getInstance().getFromWikidataQuery(
+                ? nearbyPlaces.getFromWikidataQuery(
                 context,
                 curLatLng,
                 Locale.getDefault().getLanguage())
-                : NearbyPlaces.getInstance().getFromWikiNeedsPictures();
+                : nearbyPlaces.getFromWikiNeedsPictures();
         if (curLatLng != null) {
             Timber.d("Sorting places by distance...");
             final Map<Place, Double> distances = new HashMap<>();

app/src/main/java/fr/free/nrw/commons/nearby/NearbyPlaces.java

@@ -29,13 +29,9 @@ public class NearbyPlaces {
     private static final double MAX_RADIUS = 300.0; // in kilometer
     private static final double RADIUS_MULTIPLIER = 1.618;
     private static final String WIKIDATA_QUERY_URL = "https://query.wikidata.org/sparql?query=${QUERY}";
-    private static NearbyPlaces singleton;
     private double radius = INITIAL_RADIUS;
     private List<Place> places;
 
-    private NearbyPlaces(){
-    }
-
     List<Place> getFromWikidataQuery(Context context,
                                      LatLng curLatLng,
                                      String lang) {
@@ -199,17 +195,4 @@ public class NearbyPlaces {
         }
         return places;
     }
-
-    /**
-     * Get the singleton instance of this class.
-     * The instance is created upon the first invocation of this method, and then reused.
-     *
-     * @return The singleton instance
-     */
-    public static synchronized NearbyPlaces getInstance() {
-        if (singleton == null) {
-            singleton = new NearbyPlaces();
-        }
-        return singleton;
-    }
 }