@Override
    public Object parse(SourceData sourceData, int rowIndex, Context context) {
        BigDecimal minValue = null;
        for (ValueParser valueParser : parserList) {
            Object valueObj = valueParser.parse(sourceData, rowIndex, context);
            if (valueObj == null) {
                return null;
            }

            BigDecimal value = OperatorTools.parseBigDecimal(valueObj);
            if (minValue == null || value.compareTo(minValue) < 0) {
                minValue = value;
            }
        }
        return minValue;
    }
LeastFunction  ->  LEAST(value1[, value2, ...])
description:
Return NULL if any argument is NULL.
Return the least value of the list of arguments.
inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/arithmetic/LeastFunction.java