有flink sink es8的例子吗？

import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.elasticsearch8.ElasticsearchSink;
import org.apache.flink.streaming.connectors.elasticsearch8.ElasticsearchSinkFunction;
import org.apache.flink.streaming.connectors.elasticsearch8.RequestIndexer;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class FlinkSinkES8Example {

public static void main(String[] args) throws Exception {
    // 创建 Flink 执行环境
    StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

    // 创建 Elasticsearch 客户端
    RestClientBuilder restClientBuilder = RestClient.builder(new HttpHost("localhost", 9200));
    RestClient restClient = restClientBuilder.build();

    // 创建 Elasticsearch Sink 函数
    ElasticsearchSinkFunction<String> sinkFunction = new ElasticsearchSinkFunction<String>() {

        @Override
        public void process(String element, RuntimeContext ctx, RequestIndexer indexer) {
            // 将数据转换为 Elasticsearch 文档
            Map<String, Object> document = new HashMap<>();
            document.put("message", element);

            // 将文档添加到 Elasticsearch 索引中
            indexer.add(document);
        }
    };

    // 创建 Elasticsearch Sink
    ElasticsearchSink<String> sink = new ElasticsearchSink.Builder<String>(restClient, sinkFunction)
            .setBulkFlushMaxActions(1)  // 批量写入的最大操作数
            .setBulkFlushInterval(5000)  // 批量写入的最大时间间隔
            .build();

    // 将数据流写入 Elasticsearch Sink
    DataStream<String> dataStream = env.fromElements("Hello, world!", "This is a test message.");
    dataStream.addSink(sink);

    // 执行 Flink 作业
    env.execute("Flink Sink ES8 Example");
}

}