diff --git a/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java b/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
index d4255064a..132f38600 100644
--- a/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
+++ b/src/org/kiwix/kiwixmobile/KiwixMobileActivity.java
@@ -231,6 +231,7 @@ public class KiwixMobileActivity extends AppCompatActivity {
   private boolean isFirstRun;
 
   private SharedPreferences settings;
+
   @Override
   public void onActionModeStarted(ActionMode mode) {
     if (mActionMode == null) {
@@ -774,6 +775,8 @@ public class KiwixMobileActivity extends AppCompatActivity {
           openFullScreen();
         }
         break;
+      default:
+        break;
     }
 
     return super.onOptionsItemSelected(item);
@@ -1256,16 +1259,16 @@ public class KiwixMobileActivity extends AppCompatActivity {
 
           builder.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
             public void onClick(DialogInterface dialog, int id) {
-              if(isOpenNewTabInBackground){
+              if (isOpenNewTabInBackground) {
                 newTabInBackground(url);
-                Snackbar snackbar = Snackbar.make(snackbarLayout, stringsGetter(R.string.new_tab_snackbar) , Snackbar.LENGTH_LONG)
-                .setAction(stringsGetter(R.string.open), new View.OnClickListener() {
-                  @Override
-                  public void onClick(View v) {
-                    if(mWebViews.size() > 1)
-                      selectTab(mWebViews.size() -1);
-                  }
-                });
+                Snackbar snackbar = Snackbar.make(snackbarLayout, stringsGetter(R.string.new_tab_snackbar), Snackbar.LENGTH_LONG)
+                    .setAction(stringsGetter(R.string.open), new View.OnClickListener() {
+                      @Override
+                      public void onClick(View v) {
+                        if (mWebViews.size() > 1)
+                          selectTab(mWebViews.size() - 1);
+                      }
+                    });
                 snackbar.setActionTextColor(getResources().getColor(R.color.white_undo));
                 snackbar.show();
               } else {
@@ -1384,6 +1387,9 @@ public class KiwixMobileActivity extends AppCompatActivity {
             bookmarks = new ArrayList<>(data.getStringArrayListExtra("bookmarks_array_list"));
           }
         }
+        break;
+      default:
+        break;
     }
 
     super.onActivityResult(requestCode, resultCode, data);
@@ -1673,7 +1679,7 @@ public class KiwixMobileActivity extends AppCompatActivity {
 
   private class KiwixWebViewClient extends WebViewClient {
 
-    HashMap<String, String> documentTypes = new HashMap<String, String>() {{
+    private HashMap<String, String> documentTypes = new HashMap<String, String>() {{
       put("epub", "application/epub+zip");
       put("pdf", "application/pdf");
     }};
diff --git a/src/org/kiwix/kiwixmobile/utils/DatabaseHelper.java b/src/org/kiwix/kiwixmobile/utils/DatabaseHelper.java
index c90d02206..4f54a601c 100644
--- a/src/org/kiwix/kiwixmobile/utils/DatabaseHelper.java
+++ b/src/org/kiwix/kiwixmobile/utils/DatabaseHelper.java
@@ -89,12 +89,11 @@ public class DatabaseHelper extends SQLiteOpenHelper {
         + " where " + CONTACTS_COLUMN_ZIM + " = '" + zimFile + "'", null);
     res.moveToLast();
 
-    while (res.isBeforeFirst() == false) {
+    while (!res.isBeforeFirst()) {
       array_list.add(res.getString(res.getColumnIndex(CONTACTS_COLUMN_SEARCH)));
       res.moveToPrevious();
     }
-
-
+    res.close();
     return array_list;
 
 
diff --git a/src/org/kiwix/kiwixmobile/utils/files/FileReader.java b/src/org/kiwix/kiwixmobile/utils/files/FileReader.java
index 29d96865e..823ce00bb 100644
--- a/src/org/kiwix/kiwixmobile/utils/files/FileReader.java
+++ b/src/org/kiwix/kiwixmobile/utils/files/FileReader.java
@@ -2,30 +2,28 @@ package org.kiwix.kiwixmobile.utils.files;
 
 import android.content.Context;
 
-import org.kiwix.kiwixmobile.KiwixMobileActivity;
-
 import java.io.BufferedReader;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 
 public class FileReader {
 
-    public String readFile(String filePath , Context context){
-        try {
-            StringBuilder buf = new StringBuilder();
-            InputStream json = context.getAssets().open(filePath);
-            BufferedReader in =
-                    new BufferedReader(new InputStreamReader(json, "UTF-8"));
-            String str;
+  public String readFile(String filePath, Context context) {
+    try {
+      StringBuilder buf = new StringBuilder();
+      InputStream json = context.getAssets().open(filePath);
+      BufferedReader in =
+          new BufferedReader(new InputStreamReader(json, "UTF-8"));
+      String str;
 
-            while ((str = in.readLine()) != null) {
-                buf.append(str);
-            }
+      while ((str = in.readLine()) != null) {
+        buf.append(str);
+      }
 
-            in.close();
-            return buf.toString();
-        } catch (Exception e){
-         return "";
-        }
+      in.close();
+      return buf.toString();
+    } catch (Exception e) {
+      return "";
     }
+  }
 }
diff --git a/src/org/kiwix/kiwixmobile/utils/files/RateAppCounter.java b/src/org/kiwix/kiwixmobile/utils/files/RateAppCounter.java
index 5225fb986..26217d4d7 100644
--- a/src/org/kiwix/kiwixmobile/utils/files/RateAppCounter.java
+++ b/src/org/kiwix/kiwixmobile/utils/files/RateAppCounter.java
@@ -6,34 +6,37 @@ import android.content.SharedPreferences;
 
 public class RateAppCounter {
 
-  String MASTER_NAME = "visitCounter";
-  String NOTHANKS_CLICKED = "clickedNoThanks";
-  SharedPreferences visitCounter;
+  private String MASTER_NAME = "visitCounter";
+  private String NOTHANKS_CLICKED = "clickedNoThanks";
+  private SharedPreferences visitCounter;
 
   public RateAppCounter(Context context) {
     visitCounter = context.getSharedPreferences(MASTER_NAME, 0);
-    visitCounter = context.getSharedPreferences(NOTHANKS_CLICKED,0);
+    visitCounter = context.getSharedPreferences(NOTHANKS_CLICKED, 0);
   }
 
-  public boolean getNoThanksState(){
+  public boolean getNoThanksState() {
     return visitCounter.getBoolean(NOTHANKS_CLICKED, false);
   }
-  public void setNoThanksState(boolean val){
+
+  public void setNoThanksState(boolean val) {
     SharedPreferences.Editor CounterEditor = visitCounter.edit();
     CounterEditor.putBoolean(NOTHANKS_CLICKED, val);
     CounterEditor.commit();
   }
-  public void setCount(int count) {
-    SharedPreferences.Editor CounterEditor = visitCounter.edit();
-    CounterEditor.putInt("count", count);
-    CounterEditor.commit();
 
-  }
-  public SharedPreferences.Editor getEditor(){
+  public SharedPreferences.Editor getEditor() {
     return visitCounter.edit();
   }
 
   public int getCount() {
     return visitCounter.getInt("count", 0);
   }
+
+  public void setCount(int count) {
+    SharedPreferences.Editor CounterEditor = visitCounter.edit();
+    CounterEditor.putInt("count", count);
+    CounterEditor.commit();
+
+  }
 }
diff --git a/src/org/kiwix/kiwixmobile/views/AutoCompleteAdapter.java b/src/org/kiwix/kiwixmobile/views/AutoCompleteAdapter.java
index 023741056..96484387b 100644
--- a/src/org/kiwix/kiwixmobile/views/AutoCompleteAdapter.java
+++ b/src/org/kiwix/kiwixmobile/views/AutoCompleteAdapter.java
@@ -12,10 +12,7 @@ import android.widget.TextView;
 import org.kiwix.kiwixmobile.JNIKiwix;
 
 import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
 import java.util.List;
-import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import org.kiwix.kiwixmobile.ZimContentProvider;
 
diff --git a/src/org/kiwix/kiwixmobile/views/BookmarksActivity.java b/src/org/kiwix/kiwixmobile/views/BookmarksActivity.java
index 0de29d23c..b4595350b 100644
--- a/src/org/kiwix/kiwixmobile/views/BookmarksActivity.java
+++ b/src/org/kiwix/kiwixmobile/views/BookmarksActivity.java
@@ -18,13 +18,15 @@ import android.widget.LinearLayout;
 import android.widget.ListView;
 import android.widget.TextView;
 import android.widget.Toast;
+
 import org.kiwix.kiwixmobile.R;
+
 import java.util.ArrayList;
 
 public class BookmarksActivity extends AppCompatActivity
     implements AdapterView.OnItemClickListener {
 
-  SparseBooleanArray sparseBooleanArray;
+  private SparseBooleanArray sparseBooleanArray;
   private ArrayList<String> contents;
   private ArrayList<String> tempContents;
   private ListView bookmarksList;
@@ -62,10 +64,9 @@ public class BookmarksActivity extends AppCompatActivity
         } else if (selected.contains(contents.get(position))) {
           selected.remove(contents.get(position));
           numOfSelected--;
-          if(numOfSelected == 0){
+          if (numOfSelected == 0) {
             mode.finish();
-          }
-          else {
+          } else {
             mode.setTitle(Integer.toString(numOfSelected));
           }
         }
@@ -180,7 +181,7 @@ public class BookmarksActivity extends AppCompatActivity
     super.onBackPressed();
   }
 
-  public String stringsGetter(int strId){
+  public String stringsGetter(int strId) {
     return getResources().getString(strId);
   }
 }
diff --git a/src/org/kiwix/kiwixmobile/views/KiwixWebView.java b/src/org/kiwix/kiwixmobile/views/KiwixWebView.java
index 30f989929..c1480bac6 100644
--- a/src/org/kiwix/kiwixmobile/views/KiwixWebView.java
+++ b/src/org/kiwix/kiwixmobile/views/KiwixWebView.java
@@ -35,12 +35,14 @@ import android.view.MenuItem;
 import android.view.View;
 import android.webkit.WebView;
 import android.widget.Toast;
+
+import org.kiwix.kiwixmobile.R;
+
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import org.kiwix.kiwixmobile.R;
 
 public class KiwixWebView extends WebView {
 
@@ -170,7 +172,7 @@ public class KiwixWebView extends WebView {
         || result.getType() == HitTestResult.SRC_IMAGE_ANCHOR_TYPE) {
       MenuItem saveMenu = menu.add(0, 1, 0, getResources().getString(R.string.save_media));
       saveMenu.setOnMenuItemClickListener(new MenuItem.OnMenuItemClickListener() {
-        public boolean onMenuItemClick(android.view.MenuItem item) {
+        public boolean onMenuItemClick(MenuItem item) {
           Message msg = saveHandler.obtainMessage();
           requestFocusNodeHref(msg);
           return true;