@Override
    public Object parse(SourceData sourceData, int rowIndex, Context context) {
        if (seedParser != null) {
            Object seedObj = seedParser.parse(sourceData, rowIndex, context);
            BigDecimal seedValue = OperatorTools.parseBigDecimal(seedObj);
            random.setSeed(seedValue.intValue());
        }
        return random.nextDouble();
    }
RandFunction  ->  Rand([seed])
description:
- Return a pseudo-random double precision value in the range [0.0, 1.0) if seed is NULL
- Return a pseudo-random double precision value in the range [0.0, 1.0) with an initial seed of Integer
inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/arithmetic/RandFunction.java