Spring boot中使用Elasticsearch联合查询

加入Elasticsearch依赖：

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
</dependency>

在application.yml文件配置Elasticsearch：

spring:
  elasticsearch:
    rest:
      uris: es节点1,es节点2
      username: 用户名
      password: 密码

推荐使用这种方式。

然后就可以使用下面的代码自动装配Elasticsearch的高级版客户端：

@Autowired
private RestHighLevelClient restHighLevelClient;

下面举例如何使用bool联合查询：

private static final String DATETIME_FORMAT = "yyyy-MM-dd HH:mm:ss.SSS";

public List<MsgStateDTO> queryMsgStateLogFromElasticsearch(String appId, String messageId, String receiver) {
    // 使用bool联合查询需要用到BoolQueryBuilder这个构建器，must方法表示完全匹配
    BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery()
            .must(QueryBuilders.termQuery("appId", appId));
    if (!StringUtils.isEmpty(messageId)) {
        boolQueryBuilder.must(QueryBuilders.termQuery("messageId", messageId));
    }
    if (!StringUtils.isEmpty(receiver)) {
        boolQueryBuilder.must(QueryBuilders.termQuery("receiver", receiver));
    }
    // 这里使用RangeQueryBuilder进行日期范围查询，‘createTime’是MsgStateDTO类的属性。
    // 这里表示查询到此为止3个月前的数据。
    RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("createTime.keyword")
            .format(DATETIME_FORMAT)
            .timeZone("+08:00")
            .from(LocalDateTime.now().minusMonths(3).format(DateTimeFormatter.ofPattern(DATETIME_FORMAT)))
            .to(LocalDateTime.now().format(DateTimeFormatter.ofPattern(DATETIME_FORMAT)));
    // 添加过滤条件
    boolQueryBuilder.filter(rangeQueryBuilder);
    // 构建完整的查询语句，SearchSourceBuilder构建表示从第0页开始查询10条，并根据@timestamp字段倒序，然后超时10s
    SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder()
            .query(boolQueryBuilder)
            .size(10)
            .sort(new FieldSortBuilder("@timestamp").order(SortOrder.DESC))
            .timeout(new TimeValue(10, TimeUnit.SECONDS));
    SearchRequest searchRequest = new SearchRequest();
    // 指定日志所在的索引
    searchRequest.indices(INDICES_CSP_MSG_STATE);
    searchRequest.source(searchSourceBuilder);
    log.info("执行Elasticsearch查询：{}", searchSourceBuilder);

    List<MsgStateDTO> msgStateDTOList = Collections.emptyList();
    try {
        // 执行查询
        SearchResponse searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
        // 结果映射
        SearchHit[] hits = searchResponse.getHits().getHits();
        Set<MsgStateDTO> msgStateDTOSet = new HashSet<>();
        for (SearchHit hit : hits) {
            MsgStateDTO msgStateDTO = $.json.toObject(hit.getSourceAsString(), MsgStateDTO.class);
            msgStateDTOSet.add(msgStateDTO);
        }
        msgStateDTOList = msgStateDTOSet.stream()
                .sorted(Comparator.comparing(MsgStateDTO::getCreateAt).reversed())
                .collect(Collectors.toList());
    } catch (IOException e) {
        log.error("请求日志服务异常", e);
        throw new BusinessException("请求日志服务异常");
    }
    return msgStateDTOList;
}

注释写得比较详细了，不再进一步说明。

以上，如有问题欢迎提出！