question: public void addItem ( Artist artist , int position ) { if ( artist == null ) throw new NullPointerException ( "The item cannot be null" ) ; if ( position < getItemCount ( ) || position > getItemCount ( ) ) throw new IllegalArgumentException ( "The position must be between 0 and lastIndex + 1" ) ; artists . add ( position , artist ) ; notifyItemInserted ( position ) ; }
target:  Add item in determined index