ES - RestClient 查询文档

目录

• 快速入门
• match 查询
• boolean 查询
• 排序和分页 查询
• 高亮处理

快速入门

@SpringBootTest
class SearchfDocTest {

    private RestHighLevelClient client;


    //查询所有文档
    @Test
    public void testMatchAll() throws IOException {
        //1. 准备请求对象
        SearchRequest searchRequest = new SearchRequest("hotel");
        //2. 准备DSL
       searchRequest.source().query(QueryBuilders.matchAllQuery());
        //3. 发送请求
        SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);

        //4. 解析响应解锁
        SearchHits hits = response.getHits();
        //4.1 获取搜索到的总条数
        long value = hits.getTotalHits().value;
        System.out.println("共搜索到" + value + "条数据");
        SearchHit[] hitsArr = hits.getHits();
        for (SearchHit hit : hits) {
            //获取文档soure
            String sourceAsString = hit.getSourceAsString();
            //反序列化
            HotelDoc hotel = JSON.parseObject(sourceAsString, HotelDoc.class);
            System.out.println(hotel);
        }
    }

    @BeforeEach
    void setUp() {
        this.client = new RestHighLevelClient(RestClient.builder(
                HttpHost.create("http://192.168.184.152:9200")
        ));
    }
    @AfterEach
    void tearDown() throws IOException {
        this.client.close();
    }
}

match 查询

@Test //match 查询
public void testMatch() throws IOException {
    //1. 准备请求对象
    SearchRequest searchRequest = new SearchRequest("hotel");
    //2. 准备DSL
    searchRequest.source().query(QueryBuilders.matchQuery("brand","如家"));
    //3. 发送请求
    SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
    handResponse(response);
}

boolean 查询

@Test //booleanm 查询
public void testBooleanQuery() throws IOException {
    //1. 准备请求对象
    SearchRequest searchRequest = new SearchRequest("hotel");
    //2. 准备DSL
    BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
    boolQueryBuilder.must(QueryBuilders.termQuery("name","如家"));
    boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").lte(250));
    
    searchRequest.source().query(boolQueryBuilder);
    //3. 发送请求
    SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
    handResponse(response);
}

排序和分页 查询

@Test //排序和分页 查询
public void testPageAndSort() throws IOException {
    //1. 准备请求对象
    SearchRequest searchRequest = new SearchRequest("hotel");
    //2. 准备DSL
    searchRequest.source().query(QueryBuilders.matchAllQuery());

    //排序
    searchRequest.source().sort("price", SortOrder.ASC);

    //分页
    searchRequest.source().from(0).size(10);

    //3. 发送请求
    SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
    handResponse(response);
}

高亮处理

@Test //高亮处理
public void testHighLightQuery() throws IOException {
    //1. 准备请求对象
    SearchRequest searchRequest = new SearchRequest("hotel");
    //2. 准备DSL
    searchRequest.source().query(QueryBuilders.matchQuery("all","如家"));

    // 处理高亮, 将name中包含 如家的 高亮显示
    searchRequest.source().highlighter(new HighlightBuilder().field("name").requireFieldMatch(false));
    //3. 发送请求
    SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
    handResponse(response);
}

private void handResponse(SearchResponse response) {
    //4. 解析响应结果
    SearchHits hits = response.getHits();
    //4.1 获取搜索到的总条数
    long value = hits.getTotalHits().value;
    System.out.println("共搜索到" + value + "条数据");
    SearchHit[] hitsArr = hits.getHits();
    for (SearchHit hit : hits) {
        //获取文档soure
        String sourceAsString = hit.getSourceAsString();
        //反序列化
        HotelDoc hotel = JSON.parseObject(sourceAsString, HotelDoc.class);

        Map<String, HighlightField> highlightFields = hit.getHighlightFields();;
        String s = Optional.ofNullable(highlightFields)
                .map(x -> x.get("name"))
                .map(y -> y.getFragments()[0])
                .map(z -> z.toString())
                .orElse("存在null");

        hotel.setName(s);
        System.out.println(hotel);
    }
}

结果：