Java Elastic search:获取索引的最后一个ID

import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;

import java.io.IOException;

public class ElasticsearchExample {
    public static void main(String[] args) {
        // 创建Elasticsearch客户端
        RestHighLevelClient client = createElasticsearchClient();

        // 创建搜索请求
        SearchRequest searchRequest = new SearchRequest("index_name");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        
        // 添加排序条件，按照文档的ID进行降序排序
        sourceBuilder.sort("_id", SortOrder.DESC);
        
        // 设置搜索请求的参数
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        sourceBuilder.size(1);
        sourceBuilder.timeout(TimeValue.timeValueSeconds(5));
        
        searchRequest.source(sourceBuilder);

        try {
            // 执行搜索请求
            SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
            
            // 解析搜索结果
            SearchHit[] hits = searchResponse.getHits().getHits();
            if (hits.length > 0) {
                String lastId = hits[0].getId();
                System.out.println("最后一个文档的ID：" + lastId);
            } else {
                System.out.println("索引中没有文档");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭Elasticsearch客户端
            closeElasticsearchClient(client);
        }
    }

    private static RestHighLevelClient createElasticsearchClient() {
        // 创建Elasticsearch客户端
        // 这里省略具体的创建过程，可以参考Elasticsearch官方文档或第三方库的使用说明
        return null;
    }

    private static void closeElasticsearchClient(RestHighLevelClient client) {
        // 关闭Elasticsearch客户端
        // 这里省略具体的关闭过程，可以参考Elasticsearch官方文档或第三方库的使用说明
    }
}