return ""
	}
}

// toLowerString - safely convert interface to lower string
func toLowerString(val interface{}) string {
	return strings.ToLower(toString(val))
}

// toInteger _ Safely convert interface to integer without causing panic.
func toInteger(val interface{}) (int64, error) {
	switch v := val.(type) {
	case float64:
		return int64(v), nil
	case int64:
		return v, nil
	case int:
		return int64(v), nil

                if (v.length == 1) {
                    final int x = DfTypeUtil.toInteger(v[0].trim());
                    return new Pair<>(x, x);
                }
                if (v.length == 2) {
                    final int x = DfTypeUtil.toInteger(v[0].trim());
                    final int y = DfTypeUtil.toInteger(v[1].trim());
                    return new Pair<>(x, y);
                }