ElasticSearch（四）

淡淡的烟草味﹌ 2022-06-06 06:18 154阅读 0赞

## ElasticSearch（四） ##

**1.search操作**  
注意 mapping 设置 分词器不同 查询结果也会不同

SearchResponse response = client.prepareSearch("index")
                    .setTypes("fulltext")
                    .setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
                    .setQuery(QueryBuilders.matchQuery("content", "中国"))
                    .setExplain(true)//按查询匹配度排序
                    .get();
    
            SearchHits searchHits = response.getHits();
            SearchHit[] hits = searchHits.getHits();
            for (SearchHit hit : hits) {
                Map<String, Object> source = hit.getSource();
                for (Map.Entry<String, Object> entry : source.entrySet()) {
                    System.out.println(entry.getKey()+":"+entry.getValue());
                }
            }

**2.Search 高亮显示**

HighlightBuilder builder = new HighlightBuilder()
                    .field("content").preTags("<font color='red'>").postTags("</font>");
    
            SearchResponse response = client.prepareSearch("inde")
                    .setTypes("fulltext")
                    .setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
                    .setExplain(true)
                    .setQuery(QueryBuilders.matchQuery("content", "中国"))
                    .highlighter(builder)
                    .get();
    
            SearchHits searchHits = response.getHits();
            SearchHit[] hits = searchHits.getHits();
            for (SearchHit hit : hits) {
                System.out.println("非高亮："+hit.getSourceAsString());
                Map<String, HighlightField> highlightFields = hit.getHighlightFields();
                for (Map.Entry<String, HighlightField> entry : highlightFields.entrySet()) {
                    System.out.println(entry.getKey()+":"+entry.getValue());
                }
            }

**2.Aggregations 分组筛选统计 用于数据的分析**  
注意 5.x版本 需要在设置mapping是 对分组的字段设置 fielddata：true 官网有提醒

/** * Aggregation.terms 根据某个字段进行分组 统计数量 */
        @org.junit.Test
        public void aggregation(){
            SearchResponse response = client.prepareSearch("love")
                    .setTypes("user")
                    .addAggregation(AggregationBuilders.terms("group")
                                .field("address").size(Integer.MAX_VALUE)
                    )
                    .setSize(100)
                    .get();
            Terms terms = response.getAggregations().get("group");
            Terms.Bucket 北京 = terms.getBucketByKey("北京");
            System.out.println("住在北京的有:"+北京.getDocCount());
            List<? extends Terms.Bucket> buckets = terms.getBuckets();
            for (Terms.Bucket bucket : buckets) {
                System.out.println(bucket.getKey()+" : "+bucket.getDocCount());
            }
    
            SearchHits searchHits = response.getHits();
            System.out.println("总数:"+searchHits.getTotalHits());
            SearchHit[] hits = searchHits.getHits();
            for (SearchHit hit : hits) {
                System.out.println(hit.getSourceAsString());
            }
    
    
        }
    
        /** * Aggregation 最小值 */
        @Test
        public void aggregation2(){
            SearchResponse response = client.prepareSearch("love").setTypes("user")
                    .addAggregation(AggregationBuilders.min("group")
                            .field("age")
                    ).get();
            Min min = response.getAggregations().get("group");
            System.out.println(min.getValue());
    
        }
        /** * Aggregation 最大值 */
        @Test
        public void aggregation3(){
            SearchResponse response = client.prepareSearch("love").setTypes("user")
                    .addAggregation(AggregationBuilders.max("group")
                            .field("age")
                    ).get();
            Max max = response.getAggregations().get("group");
            System.out.println(max.getValue());
    
        }
    
        /** * Aggregation 求和 */
        @Test
        public void aggregation4(){
            SearchResponse response = client.prepareSearch("love")
                    .setTypes("user").addAggregation(
                            AggregationBuilders.sum("group")
                                    .field("age")
                    ).get();
            Sum sum = response.getAggregations().get("group");
            System.out.println(sum.getValue());
        }
    
    
        /** * Aggregation 统计 */
        @Test
        public void aggregation5(){
            SearchResponse response = client.prepareSearch("love")
                    .setTypes("user").addAggregation(
                            AggregationBuilders.stats("group")
                                    .field("age")
                    ).get();
            Stats stat = response.getAggregations().get("group");
            System.out.println("年龄平均值："+stat.getAvg());
            System.out.println("年龄最大值："+stat.getMax());
            System.out.println("年龄最小值："+stat.getMin());
            System.out.println("年龄求和："+stat.getSum());
            System.out.println("年龄数量："+stat.getCount());
        }

//还有一些其他的 用的时候再去官网看api吧