cannot be cast to org.elasticsearch.search.aggregations.bucket.terms.StringTerms

java.lang.ClassCastException: org.elasticsearch.search.aggregations.bucket.terms.UnmappedTerms cannot be cast to org.elasticsearch.search.aggregations.bucket.terms.StringTerms

方便同学们检索： 黑马 乐优商城 leyou-search  SearchService.java

先说结论：es中的结构错误，存在非String类型，下次碰到直接 GET goods/_search

（图1  插件kibana）

（图2）

如何找到错误

测试类1：操作系统 测试正常

            String getName = "操作系统";
            NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
            //AggregationBuilders：继承自Object
//        queryBuilder.addAggregation(AggregationBuilders.terms("brandAgg"));  //error
            queryBuilder.addAggregation(AggregationBuilders.terms(getName).field("specs." + getName + ".keyword"));
            //new String[]{} 或者null
            queryBuilder.withSourceFilter(new FetchSourceFilter(new String[]{},null));
//        Page items = this.itemRepository.search(queryBuilder.build());
            AggregatedPage items = (AggregatedPage)this.goodsRepository.search(queryBuilder.build());
            //根据字段类型强转 Brand是String，term聚合，所以结果要强转为StringTerm类型
            StringTerms brandAgg = (StringTerms)items.getAggregation(getName);
//        StringTerms.Bucket bucketHUAWEI = brandAgg.getBucketByKey("华为");
            List buckets = brandAgg.getBuckets();
            buckets.forEach(bucket -> {
                System.out.println(bucket.getKey());
            });

测试2：错误

NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
        // 查询要聚合的规格参数
        List params = this.specificationClient.queryParams(null, 76l, null, true);
        params.forEach(param -> {
            System.out.println(param.getName());
            queryBuilder.addAggregation(AggregationBuilders.terms(param.getName()).field("specs." + param.getName() + ".keyword"));
        });
        // 执行聚合查询
        AggregatedPage goodsPage = (AggregatedPage)this.goodsRepository.search(queryBuilder.build());

        // 定义一个集合，收集聚合结果集
        List> paramMapList = new ArrayList<>();
        // 解析聚合查询的结果集
        Map aggregationMap = goodsPage.getAggregations().asMap();
        for (Map.Entry entry : aggregationMap.entrySet()) {
            Map map = new HashMap<>();
            // 放入规格参数名
            System.out.println(entry.getKey());
            map.put("k", entry.getKey());
            // 收集规格参数值
            List