SpringDataElasticsearch的API用法

SpringDataElasticsearch

需要注意的是，SpringDataElasticsearch底层使用的不是Elasticsearch提供的RestHighLevelClient，而是TransportClient，并不采用Http协议通信，而是访问elasticsearch对外开放的tcp端口，我们之前集群配置中，设置的分别是：9300

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SDE的索引数据CRUD并没有封装在ElasticsearchTemplate中，而是有一个叫做ElasticsearchRepository的接口： 这个接口操作没有高亮显示

public interface GoodsRepository extends ElasticsearchRepository<Goods, Long> {
}
//就可以注入使用了
@Autowired
private GoodsRepository goodsRepository;

find save findall delete : 操作索引数据的增删改查

search : 搜索

 //查询条件构建器
        NativeSearchQueryBuilder searchQueryBuilder = new NativeSearchQueryBuilder();

        //查询
        searchQueryBuilder.withQuery(QueryBuilders.matchAllQuery());
        //排序
        searchQueryBuilder.withSort(SortBuilders.fieldSort("price").order(SortOrder.ASC));
        //分页
        searchQueryBuilder.withPageable(PageRequest.of(0, 5));
        //高亮
        searchQueryBuilder.withHighlightFields(new HighlightBuilder.Field("title"));
        searchQueryBuilder.withHighlightBuilder(new HighlightBuilder().preTags("").postTags(""));
        //聚合
        searchQueryBuilder.addAggregation(AggregationBuilders.terms("brandAgg").field("brand"));

        //条件查询的结果 需要 手动强转成page的实现类AggregatedPage,  因为AggregatedPage里面有聚合 高亮
        AggregatedPage<Goods> result = (AggregatedPage<Goods>) goodsRepository.search(searchQueryBuilder.build());


        //总条数
        long totalElements = result.getTotalElements();
        System.out.println("totalElements = " + totalElements);
        //总页数
        int totalPages = result.getTotalPages();
        System.out.println("totalPages = " + totalPages);
        //当前页结果
        List<Goods> goods = result.getContent();
        goods.forEach(System.out::println);

        //获取到聚合aggregations
        Aggregations aggs = result.getAggregations();
        //根据聚合名字 获取到 聚合对象
        Terms brandAgg = aggs.get("brandAgg");
        //获取到桶
        List<? extends Terms.Bucket> buckets = brandAgg.getBuckets();
        //把桶中的聚合结果取出来打印
        for (Terms.Bucket bucket : buckets) {
            System.out.println(bucket.getKeyAsString() + bucket.getDocCount());
        }

ElasticsearchRepository这个接口 没有提供高亮

因为高亮需要自定义结果, 然而这个接口没有给我们自定义结果的机会,都是封装好的.

所以高亮需要使用下面的 ElasticsearchTemplate模板

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如果觉得上述接口依然不符合你的需求，SDE也支持原生查询，这个时候还是使用ElasticsearchTemplate : spring已经整合了

 @Autowired
 private ElasticsearchTemplate esTemplate;
 

高亮显示:

    @Autowired
    private ElasticsearchTemplate esTemplate;

    @Test
    public void search() {
        //查询条件构建器
        NativeSearchQueryBuilder searchQueryBuilder = new NativeSearchQueryBuilder();
        //查询
        searchQueryBuilder.withQuery(QueryBuilders.matchQuery("title","小米手机"));
        //排序
        searchQueryBuilder.withSort(SortBuilders.fieldSort("price").order(SortOrder.ASC));
        //分页
        searchQueryBuilder.withPageable(PageRequest.of(0, 5));
        //高亮
        searchQueryBuilder.withHighlightFields(new HighlightBuilder.Field("title"));
        searchQueryBuilder.withHighlightBuilder(new HighlightBuilder().preTags("").postTags(""));
        //聚合
        searchQueryBuilder.addAggregation(AggregationBuilders.terms("brandAgg").field("brand"));

        //搜索结果 高亮显示
        AggregatedPage<Goods> result = esTemplate.queryForPage(searchQueryBuilder.build(), Goods.class, new MySearchResultMapper());



        //总条数
        long totalElements = result.getTotalElements();
        System.out.println("totalElements = " + totalElements);
        //总页数
        int totalPages = result.getTotalPages();
        System.out.println("totalPages = " + totalPages);
        //当前页结果
        List<Goods> goods = result.getContent();
        goods.forEach(System.out::println);

        //获取到聚合aggregations
        Aggregations aggs = result.getAggregations();
        //根据聚合名字 获取到 聚合对象
        Terms brandAgg = aggs.get("brandAgg");
        //获取到桶
        List<? extends Terms.Bucket> buckets = brandAgg.getBuckets();
        //把桶中的聚合结果取出来打印
        for (Terms.Bucket bucket : buckets) {
            System.out.println(bucket.getKeyAsString() + bucket.getDocCount());
        }

    }


    @Autowired
    private Gson gson;
    
    //自定义接口  用于解析高亮
    class MySearchResultMapper implements SearchResultMapper{

        @Override
        public <T> AggregatedPage<T> mapResults(SearchResponse response, Class<T> clazz, Pageable pageable) {

            String scrollId = response.getScrollId();
            Aggregations aggregations = response.getAggregations();
            //获取命中
            SearchHits searchHits = response.getHits();
            float maxScore = searchHits.getMaxScore();
            long total = searchHits.getTotalHits();

            //获取到命中里的每一个hits
            SearchHit[] hits = searchHits.getHits();

            ArrayList<T> content = new ArrayList<>();

            for (SearchHit hit : hits) {
                //获取到"_source 里的数据
                String json = hit.getSourceAsString();
                T t = gson.fromJson(json, clazz);

                //每一个hit对象 里面 都有高亮
                Map<String, HighlightField> highlightFields = hit.getHighlightFields();
                Set<Map.Entry<String, HighlightField>> entries = highlightFields.entrySet();
                for (Map.Entry<String, HighlightField> entry : entries) {
                    //获取到高亮的字段
                    String field = entry.getKey();
                    //获取到高亮字段的值
                    HighlightField highlightField = entry.getValue();
                    String value = StringUtils.join(highlightField.getFragments());
                    //反射  设置值
                    try {
                        BeanUtils.setProperty(t, field, value);
                    }  catch (Exception e) {
                        e.printStackTrace();
                    }
                }
                content.add(t);
            }
            return new AggregatedPageImpl<>(content, pageable, total, aggregations, scrollId, maxScore);
        }
    }