diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.java b/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.java
deleted file mode 100644
index 67cd7168df..0000000000
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.java
+++ /dev/null
@@ -1,89 +0,0 @@
-/*
- * Kiwix Android
- * Copyright (c) 2019 Kiwix <android.kiwix.org>
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- *
- */
-package org.kiwix.kiwixmobile.core.data.local.dao;
-
-import com.yahoo.squidb.data.SquidCursor;
-import com.yahoo.squidb.sql.Query;
-import java.io.File;
-import java.util.ArrayList;
-import javax.inject.Inject;
-import org.kiwix.kiwixmobile.core.data.local.KiwixDatabase;
-import org.kiwix.kiwixmobile.core.data.local.entity.BookDatabaseEntity;
-import org.kiwix.kiwixmobile.core.entity.LibraryNetworkEntity.Book;
-import org.kiwix.kiwixmobile.core.utils.files.FileUtils;
-
-/**
- * Dao class for books
- */
-
-@Deprecated
-public class BookDao {
-  private final KiwixDatabase kiwixDatabase;
-
-  @Inject
-  public BookDao(KiwixDatabase kiwixDatabase) {
-    this.kiwixDatabase = kiwixDatabase;
-  }
-
-  private void setBookDetails(Book book, SquidCursor<BookDatabaseEntity> bookCursor) {
-    book.setId(bookCursor.get(BookDatabaseEntity.BOOK_ID));
-    book.setTitle(bookCursor.get(BookDatabaseEntity.TITLE));
-    book.setDescription(bookCursor.get(BookDatabaseEntity.DESCRIPTION));
-    book.setLanguage(bookCursor.get(BookDatabaseEntity.LANGUAGE));
-    book.setCreator(bookCursor.get(BookDatabaseEntity.BOOK_CREATOR));
-    book.setPublisher(bookCursor.get(BookDatabaseEntity.PUBLISHER));
-    book.setDate(bookCursor.get(BookDatabaseEntity.DATE));
-    book.setFile(new File(bookCursor.get(BookDatabaseEntity.URL)));
-    book.setArticleCount(bookCursor.get(BookDatabaseEntity.ARTICLE_COUNT));
-    book.setMediaCount(bookCursor.get(BookDatabaseEntity.MEDIA_COUNT));
-    book.setSize(bookCursor.get(BookDatabaseEntity.SIZE));
-    book.setFavicon(bookCursor.get(BookDatabaseEntity.FAVICON));
-    book.setBookName(bookCursor.get(BookDatabaseEntity.NAME));
-  }
-
-  public ArrayList<Book> getBooks() {
-    ArrayList<Book> books = new ArrayList<>();
-    try {
-      SquidCursor<BookDatabaseEntity> bookCursor = kiwixDatabase.query(BookDatabaseEntity.class,
-        Query.select());
-      while (bookCursor.moveToNext()) {
-        Book book = new Book();
-        setBookDetails(book, bookCursor);
-        books.add(book);
-      }
-    } catch (Exception exception) {
-      exception.printStackTrace();
-    }
-    return filterBookResults(books);
-  }
-
-  public ArrayList<Book> filterBookResults(ArrayList<Book> books) {
-    ArrayList<Book> filteredBookList = new ArrayList<>();
-    for (Book book : books) {
-      if (!FileUtils.hasPart(book.getFile())) {
-        if (book.getFile().exists()) {
-          filteredBookList.add(book);
-        } else {
-          kiwixDatabase.deleteWhere(BookDatabaseEntity.class,
-            BookDatabaseEntity.URL.eq(book.getFile().getPath()));
-        }
-      }
-    }
-    return filteredBookList;
-  }
-}
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.kt
new file mode 100644
index 0000000000..bb99d26a3f
--- /dev/null
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/data/local/dao/BookDao.kt
@@ -0,0 +1,92 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2019 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+package org.kiwix.kiwixmobile.core.data.local.dao
+
+import com.yahoo.squidb.data.SquidCursor
+import com.yahoo.squidb.sql.Query
+import org.kiwix.kiwixmobile.core.data.local.KiwixDatabase
+import org.kiwix.kiwixmobile.core.data.local.entity.BookDatabaseEntity
+import org.kiwix.kiwixmobile.core.entity.LibraryNetworkEntity
+import org.kiwix.kiwixmobile.core.utils.files.FileUtils.hasPart
+import java.io.File
+import javax.inject.Inject
+
+/**
+ * Dao class for books
+ */
+@Deprecated("")
+class BookDao @Inject constructor(private val kiwixDatabase: KiwixDatabase) {
+  private fun setBookDetails(
+    book: LibraryNetworkEntity.Book,
+    bookCursor: SquidCursor<BookDatabaseEntity>
+  ) {
+    book.id = bookCursor.get(BookDatabaseEntity.BOOK_ID)!!
+    book.title = bookCursor.get(BookDatabaseEntity.TITLE)!!
+    book.description = bookCursor.get(BookDatabaseEntity.DESCRIPTION)
+    book.language = bookCursor.get(BookDatabaseEntity.LANGUAGE)!!
+    book.creator = bookCursor.get(BookDatabaseEntity.BOOK_CREATOR)!!
+    book.publisher = bookCursor.get(BookDatabaseEntity.PUBLISHER)!!
+    book.date = bookCursor.get(BookDatabaseEntity.DATE)!!
+    book.file = bookCursor.get(BookDatabaseEntity.URL)?.let(::File)
+    book.articleCount = bookCursor.get(BookDatabaseEntity.ARTICLE_COUNT)
+    book.mediaCount = bookCursor.get(BookDatabaseEntity.MEDIA_COUNT)
+    book.size = bookCursor.get(BookDatabaseEntity.SIZE)!!
+    book.favicon = bookCursor.get(BookDatabaseEntity.FAVICON)!!
+    book.bookName = bookCursor.get(BookDatabaseEntity.NAME)
+  }
+
+  val books: ArrayList<LibraryNetworkEntity.Book>
+    @Suppress("TooGenericExceptionCaught")
+    get() {
+      val books = ArrayList<LibraryNetworkEntity.Book>()
+      try {
+        val bookCursor = kiwixDatabase.query(
+          BookDatabaseEntity::class.java,
+          Query.select()
+        )
+        while (bookCursor.moveToNext()) {
+          val book = LibraryNetworkEntity.Book()
+          setBookDetails(book, bookCursor)
+          books.add(book)
+        }
+      } catch (exception: Exception) {
+        exception.printStackTrace()
+      }
+      return filterBookResults(books)
+    }
+
+  fun filterBookResults(
+    books: ArrayList<LibraryNetworkEntity.Book>
+  ): ArrayList<LibraryNetworkEntity.Book> {
+    val filteredBookList = ArrayList<LibraryNetworkEntity.Book>()
+    books
+      .asSequence()
+      .filterNot { it.file?.let(::hasPart) == true }
+      .forEach {
+        if (it.file?.exists() == true) {
+          filteredBookList.add(it)
+        } else {
+          kiwixDatabase.deleteWhere(
+            BookDatabaseEntity::class.java,
+            BookDatabaseEntity.URL.eq(it.file?.path)
+          )
+        }
+      }
+    return filteredBookList
+  }
+}