@Override
    public Object parse(SourceData sourceData, int rowIndex, Context context) {
        Object cntObj = cntParser.parse(sourceData, rowIndex, context);
        if (cntObj == null) {
            return null;
        }
        int cnt = OperatorTools.parseBigDecimal(cntObj).intValue();
        if (cnt <= 0) {
            return "";
        }
        StringBuilder builder = new StringBuilder(cnt);
        for (int i = 0; i < cnt; i++) {
            builder.append(" ");
        }
        return builder.toString();
    }
SpaceFunction  ->  SPACE(N)
description:
- Return NULL if 'N' is NULL
- Return "" if 'N' is less than or equal to 0
- Return a string consisting of 'N' space characters
inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/string/SpaceFunction.java