@Override
    public Number getNumber(@NonNull String key) {
        if (key == null) { throw new IllegalArgumentException("key cannot be null."); }

        final int index = indexForColumnName(key);
        return index >= 0 ? getNumber(index) : null;
    }
@ Override public Number getNumber ( @ NonNull String key ) { if ( key == null ) { throw new IllegalArgumentException ( "key cannot be null." ) ; } final int index = indexForColumnName ( key ) ; return index >= 0 ? getNumber ( index ) : null ; }
The projecting result value for the given key  as a Number object
Returns null if the key doesn't exist.

@param key The select result key.
@return The Number object.