private static List<FieldRelation> createSplitterFieldRelations(
            List<StreamField> fieldList, String transformName,
            SplitterDefinition splitterDefinition, String preNodes,
            Map<String, StreamField> constantFieldMap) {
        Preconditions.expectNotBlank(preNodes, ErrorCodeEnum.INVALID_PARAMETER,
                "PreNodes of splitter should not be null");
        String preNode = preNodes.split(",")[0];
        List<SplitRule> splitRules = splitterDefinition.getSplitRules();
        Set<String> splitFields = Sets.newHashSet();
        List<FieldRelation> fieldRelations = splitRules.stream()
                .map(splitRule -> parseSplitRule(splitRule, splitFields, transformName, preNode))
                .reduce(Lists.newArrayList(), (list1, list2) -> {
                    list1.addAll(list2);
                    return list1;
                });
        List<StreamField> filteredFieldList = fieldList.stream()
                .filter(streamFieldInfo -> !splitFields.contains(streamFieldInfo.getFieldName()))
                .collect(Collectors.toList());
        fieldRelations.addAll(createFieldRelations(filteredFieldList, constantFieldMap));
        return fieldRelations;
    }
Create relation of fields in split function.
inlong-manager/manager-pojo/src/main/java/org/apache/inlong/manager/pojo/sort/util/FieldRelationUtils.java