java 执行es中的sql

import org.apache.http.HttpHost;

import org.elasticsearch.client.Request;

import org.elasticsearch.client.Response;

import org.elasticsearch.client.RestClient;

import org.elasticsearch.client.RestHighLevelClient;

import java.io.*;

import java.nio.charset.StandardCharsets;

import java.util.HashSet;

public class ReadEsSql {

public static void main(String[] args) {

try (RestHighLevelClient client = new RestHighLevelClient(

RestClient.builder(

new HttpHost("host1", 9200, "http"),

new HttpHost("host2", 9200, "http"),

new HttpHost("host3", 9200, "http")

))) {

//写本地

BufferedWriter writer = new BufferedWriter(new FileWriter("data/result.txt", true));

String sql = String.format("{\"query\": \"select * from \\\"index\\\" \" } ,\"fetch_size\":100000");

Request request = new Request("POST", "/_sql?format=txt");

request.setJsonEntity(sql);

Response response = client.getLowLevelClient().performRequest(request);

// 正确处理响应实体

BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), StandardCharsets.UTF_8));

String data;

HashSet<String> set = new HashSet<>();

while ((data = reader.readLine()) != null) {

set.add(data);

}

set.forEach(it -> {

try {

writer.write(it + "\n");

} catch (IOException e) {

throw new RuntimeException(e);

}

});

writer.flush();

} catch (IOException e) {

e.printStackTrace();

}

}

}