难道只能查出来遍历过滤？

用elemMatch只能返回第一个匹配的

楼主这个问题有没有解决方案啊？我百度谷歌都找了，官方文档也看了，关于对子文档查询都是使用elemMatch，都只返回查到的第一个元素。遍历显然太不理想了，我被这个问题搞了一个月了。

unwind后再map

unwind后再匹配一下

/**
     * Aggregation agg = newAggregation(
     *                     unwind("rule"),     // 将list 拆分查找
     *                     match(criteria),    // 匹配
     *                     project("rule"),    // 输出流(输出到下一个环节或输出)
     *                     skip(index),        // index
     *                     limit(pageSize));   // 页数目
     *             AggregationResults<RuleScheme.RuleGroupFinderMap> results = mongoTemplate.aggregate(agg, "ruleScheme", 
     *             RuleScheme.RuleGroupFinderMap.class);
     * @param ruleId
     * @param groupName
     * @param status
     * @param type
     * @param pageNumber
     * @param pageSize
     * @return
     */
    public Object findRuleGroupBy(String ruleId, String groupName, String status, String type, Integer
            pageNumber, Integer pageSize) {

        // 这里注意"_id"
        Criteria criteria = where("_id").is(ruleId);
        if (StringUtils.isNotBlank(groupName)) {
            criteria.and("rule.groupName").is(groupName);
        }
        if (StringUtils.isNotBlank(status)) {
            criteria.and("rule.status").is(status);
        }
        if (StringUtils.isNotBlank(type)) {
            criteria.and("rule.groupName").is(type);
        }

        // 分页
        // RuleScheme.RuleGroupFinderMap 这个类的属性一个是id,一个是map(如下)
        // private String id;
        // private Map rule;
        if (ObjectUtils.allNotNull(pageNumber, pageSize)) {
            Aggregation aggNoPage = newAggregation(
                    unwind("rule"),
                    match(criteria),
                    project("rule"));
            AggregationResults<RuleScheme.RuleGroupFinderMap> resultsNoPage =
                    mongoTemplate.aggregate(aggNoPage, "ruleScheme", RuleScheme.RuleGroupFinderMap.class);
            long totalSize = resultsNoPage.getMappedResults().size();

            long index = (pageNumber - 1) * pageSize;
            Aggregation agg = newAggregation(
                    unwind("rule"),
                    match(criteria),
                    project("rule"),
                    skip(index),
                    limit(pageSize));
            AggregationResults<RuleScheme.RuleGroupFinderMap> results = mongoTemplate.aggregate(agg, "ruleScheme", RuleScheme.RuleGroupFinderMap.class);
            List<RuleScheme.RuleGroupFinderMap> resultList = results.getMappedResults();

            //page
            CustomPage<RuleScheme.RuleGroupFinderMap> customPage = new CustomPage<>(pageNumber, pageSize, totalSize);
            customPage.setRows(resultList);
            return customPage;
        } else {
            // 不分页
            Aggregation aggNoPage = newAggregation(
                    unwind("rule"),
                    match(criteria),
                    project("rule"));
            AggregationResults<RuleScheme.RuleGroupFinderMap> resultsNoPage =
                    mongoTemplate.aggregate(aggNoPage, "ruleScheme", RuleScheme.RuleGroupFinderMap.class);
            List<RuleScheme.RuleGroupFinderMap> resultList = resultsNoPage.getMappedResults();
            return resultList;
        }
    }