Elasticsearch：搜索和分页入门

Myth丶恋晨 2024-03-24 09:03 12阅读 0赞

import org.apache.http.HttpHost;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    
    @Configuration
    public class ElasticsearchConfig {
    
    
        @Bean
        public RestHighLevelClient restHighLevelClient(){
            return new RestHighLevelClient(RestClient.builder(
                    HttpHost.create("http://192.168.150.101:9200")
            ));
        }
    }

import com.alibaba.fastjson.JSON;
    import lombok.extern.slf4j.Slf4j;
    import org.apache.commons.lang3.StringUtils;
    import org.elasticsearch.action.search.SearchRequest;
    import org.elasticsearch.action.search.SearchResponse;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.elasticsearch.index.query.QueryBuilders;
    import org.elasticsearch.search.SearchHit;
    import org.elasticsearch.search.SearchHits;
    
    @Slf4j
    @Service
    public class DemoService extends ServiceImpl<DemoMapper, Demo> implements IDemoService {
    
        @Autowired
        private RestHighLevelClient restHighLevelClient;
    
        @Override
        public PageResult search(RequestParams params) {
            try {
                // 1.准备Request
                SearchRequest request = new SearchRequest("demo");
                // 2.准备请求参数
                // 2.1.query
                String key = params.getKey();
                if (StringUtils.isNotBlank(key)) {
                    // 不为空，根据关键字查询
                    request.source().query(QueryBuilders.matchQuery("all", key));
                } else {
                    // 为空，查询所有
                    request.source().query(QueryBuilders.matchAllQuery());
                }
                // 2.2.分页
                int page = params.getPage();
                int size = params.getSize();
                request.source().from((page - 1) * size).size(size);
    
                // 3.发送请求
                SearchResponse response = restHighLevelClient.search(request, RequestOptions.DEFAULT);
                // 4.解析响应
                return handleResponse(response);
            } catch (IOException e) {
                throw new RuntimeException("搜索数据失败", e);
            }
        }
    
    
        private PageResult handleResponse(SearchResponse response) {
            SearchHits searchHits = response.getHits();
            // 4.1.总条数
            long total = searchHits.getTotalHits().value;
            // 4.2.获取文档数组
            SearchHit[] hits = searchHits.getHits();
            // 4.3.遍历
            List<Demo> demoList = new ArrayList<>(hits.length);
            for (SearchHit hit : hits) {
                // 4.4.获取source
                String json = hit.getSourceAsString();
                // 4.5.反序列化，非高亮的
                Demo demo= JSON.parseObject(json, Demo.class);
                // 4.9.放入集合
                demoList.add(demo);
            }
            return new PageResult(total, hotels);
        }
    }