如何在Elasticsearch中检查索引是否为空？

import org.elasticsearch.action.admin.indices.stats.IndicesStatsRequest;
import org.elasticsearch.action.admin.indices.stats.IndicesStatsResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.unit.ByteSizeUnit;
import org.elasticsearch.common.unit.ByteSizeValue;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

public class CheckIndexEmpty {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient();

        IndicesStatsRequest request = new IndicesStatsRequest();
        request.indices("your_index_name");

        // 设置超时时间
        request.timeout(TimeValue.timeValueMinutes(1));

        // 设置查询条件，查询索引中的文档数量
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        request.query(sourceBuilder);

        // 执行请求
        IndicesStatsResponse response = client.indices().stats(request, RequestOptions.DEFAULT);

        // 获取索引中的文档数量
        long docCount = response.getTotal().getDocs().getCount();

        if (docCount > 0) {
            System.out.println("索引不为空");
        } else {
            System.out.println("索引为空");
        }

        client.close();
    }
}