A cursor adapter implementation for recycler views in android

GenericRecylcerViewCursorAdapter.java

import android.database.Cursor;
import android.database.DataSetObserver;
import android.support.v7.widget.RecyclerView;

/**
 * Created by nilarnab on 7/8/16.
 */
public abstract class GenericRecyclerViewCursorAdapter<Vh extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<Vh> {
    private Cursor mCursor;
    private DataSetObserver mDataSetObserver;
    
    public GenericRecyclerViewCursorAdapter(Cursor cursor) {
        mCursor = cursor;
        mDataSetObserver = new NotifyingDataSetObserver();
        if (mCursor != null) {
            mCursor.registerDataSetObserver(mDataSetObserver);
        }

        setHasStableIds(true);
    }

    public Cursor getCursor() {
        return mCursor;
    }

    @Override
    public int getItemCount() {
        return mCursor != null ? mCursor.getCount() : 0;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    public abstract void onBindViewHolder(Vh viewHolder, Cursor cursor);

    @Override
    public void onBindViewHolder(Vh viewHolder, int position) {
        if (mCursor == null || !mCursor.moveToPosition(position)) {
            throw new IllegalStateException("couldn't move cursor to position " + position);
        }
        onBindViewHolder(viewHolder, mCursor);
    }

    public Cursor swapCursor(Cursor newCursor) {
        if (newCursor == mCursor) {
            return null;
        }
        final Cursor oldCursor = mCursor;
        if (oldCursor != null && mDataSetObserver != null) {
            oldCursor.unregisterDataSetObserver(mDataSetObserver);
        }
        mCursor = newCursor;
        if (mCursor != null) {
            if (mDataSetObserver != null) {
                mCursor.registerDataSetObserver(mDataSetObserver);
            }
            notifyDataSetChanged();
        } else {
            notifyDataSetChanged();
            //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter
        }
        return oldCursor;
    }

    private class NotifyingDataSetObserver extends DataSetObserver {
        @Override
        public void onChanged() {
            super.onChanged();
            notifyDataSetChanged();
        }

        @Override
        public void onInvalidated() {
            super.onInvalidated();
            notifyDataSetChanged();
            //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter
        }
    }

}