Android: Null object reference in adapter for for recyclerview

Question

Trying to create a recyclerview for displaying data from the db. Keep getting this null pointer error on the same line. According to other sources, its because I do not instantiate the arraylists, so I fixed that I guess. I'm trying to make a simple book library, just as an example to use it later on my college project. The null pointer exception occurs on line 36, where the book author's position is passed to get()

package com.example.sql_recyclerview;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
import androidx.recyclerview.widget.RecyclerView;
import org.w3c.dom.Text;
import java.util.ArrayList;
    public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder>
    {
        private Context context;
        private ArrayList book_id, book_title, book_author, book_pages;
        CustomAdapter(Context context, ArrayList book_id, ArrayList book_title, ArrayList book_author, ArrayList book_pages)
        {
            this.context = context;
            this.book_id = book_id;
            this.book_title = book_title;
            this.book_pages = book_pages;
        }
        @NonNull
        @Override
        public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType)
        {
            LayoutInflater inflater = LayoutInflater.from(context);
            View view = inflater.inflate(R.layout.my_row, parent, false);
            return new MyViewHolder(view);
        }
        @Override
        public void onBindViewHolder(@NonNull MyViewHolder holder, int position)
        {
            holder.book_id_txt.setText(String.valueOf(book_id.get(position)));
            holder.book_title_txt.setText(String.valueOf(book_title.get(position)));
            holder.book_author_txt.setText(String.valueOf(book_author.get(position)));
            holder.book_pages_txt.setText(String.valueOf(book_pages.get(position)));
        }
        @Override
        public int getItemCount()
        {
            return book_id.size();
        }
        public class MyViewHolder extends RecyclerView.ViewHolder
        {
            TextView book_id_txt, book_title_txt, book_author_txt, book_pages_txt;
            public MyViewHolder(@NonNull View itemView)
            {
                super(itemView);
                book_id_txt = itemView.findViewById(R.id.book_id_txt);
                book_title_txt = itemView.findViewById(R.id.book_title_txt);
                book_author_txt = itemView.findViewById(R.id.book_author_txt);
                book_pages_txt = itemView.findViewById(R.id.book_pages_txt);
            }
        }
    }