本文介绍如何使用 Java 语言，通过 opensearch-java 客户端连接 OpenSearch 实例，并为您提供示例代码。

准备工作

• 提前创建 OpenSearch 实例，并确保为正常运行状态。创建实例的具体操作，请参见创建实例。
• 您在连接实例前，请先在实例详情页面获取实例访问地址、实例访问用户。
  

  说明

  • 对于需要使用证书连接的 HTTPS 协议实例，还需要下载证书并保存到本地路径。
  • 如果遗忘实例访问用户（admin）的密码，可以选择重置密码。具体操作步骤，请参见重置访问密码。
  • 如果需要使用实例公网地址访问，您可以为实例开启公网访问，然后绑定一个弹性公网 EIP。具体操作步骤，请参见配置实例公网访问。
• 运行 Java 代码的服务器需要提前安装 Java 环境，安装 11 或以上版本 JDK；以及安装 3.5 或以上版本 Maven。具体操作，请参见安装JDK和安装Maven。

注意事项

• 支持 Java 8/11/17/21，如果 Java 版本不匹配请先进行版本升级。
• 确保运行 Java 代码的服务器与 OpenSearch 实例网络互通。
  • 如果运行 Java 代码的服务器与实例在相同的私有网络 VPC 中，则可以通过实例的私网地址进行连接。
  • 如果运行 Java 代码的服务器在公网环境下，则可以通过实例的公网地址进行连接。具体操作步骤，请参见配置实例公网访问。

添加依赖

Maven

<dependency>
  <groupId>org.opensearch.client</groupId>
  <artifactId>opensearch-java</artifactId>
  <version>2.21.0</version>
</dependency>

<dependency>
  <groupId>org.apache.httpcomponents.client5</groupId>
  <artifactId>httpclient5</artifactId>
  <version>5.2.1</version>
</dependency>

Gradle

dependencies {
  implementation 'org.opensearch.client:opensearch-java:2.21.0'
  implementation 'org.apache.httpcomponents.client5:httpclient5:5.2.1'
}

连接实例

运行以下程序，返回如下类似信息：

current cluster status is: GREEN

通过 Https 证书连接实例

该场景适用于连接访问方式为 HTTPS 的 OpneSearch 实例，且需要认证实例的 HTTPS 证书。
示例代码如下：

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;

import org.apache.hc.client5.http.auth.AuthScope;
import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
import org.apache.hc.client5.http.config.ConnectionConfig;
import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManager;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
import org.apache.hc.client5.http.ssl.ClientTlsStrategyBuilder;
import org.apache.hc.core5.function.Factory;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.nio.ssl.TlsStrategy;
import org.apache.hc.core5.reactor.ssl.TlsDetails;
import org.apache.hc.core5.ssl.SSLContextBuilder;
import org.apache.hc.core5.util.Timeout;
import org.opensearch.client.opensearch.OpenSearchClient;
import org.opensearch.client.opensearch.cat.HealthRequest;
import org.opensearch.client.opensearch.cluster.HealthResponse;
import org.opensearch.client.transport.OpenSearchTransport;
import org.opensearch.client.transport.httpclient5.ApacheHttpClient5TransportBuilder;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.KeyStore;
import java.security.cert.CertificateFactory;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.TimeUnit;


public class OSinitClientWithCA {

  public OpenSearchClient initClientWithCA(List<HttpHost> hosts, String caPath, String user, String password) throws Exception {

    if (hosts == null || hosts.isEmpty()) {
      throw new IllegalArgumentException("invalid empty hosts");
    }
    BasicCredentialsProvider provider = new BasicCredentialsProvider();
    for (HttpHost host : hosts) {
      provider.setCredentials(new AuthScope(host), new UsernamePasswordCredentials(user, password.toCharArray()));
    }

    SSLContext sslContext;
    try {
      InputStream is = Files.newInputStream(Paths.get(caPath));
      KeyStore trustStore = KeyStore.getInstance("pkcs12");
      trustStore.load(null,null);
      trustStore.setCertificateEntry("ca", CertificateFactory.getInstance("X.509").generateCertificate(is));
      sslContext = new SSLContextBuilder().loadTrustMaterial(trustStore, null).build();
    } catch (Exception e) {
      // add your own log here
      throw e;
    }

    final ApacheHttpClient5TransportBuilder builder = ApacheHttpClient5TransportBuilder.builder(host);
    builder.setHttpClientConfigCallback(httpClientBuilder -> {
      final TlsStrategy tlsStrategy = ClientTlsStrategyBuilder.create()
              .setSslContext(sslContext)
              // See https://issues.apache.org/jira/browse/HTTPCLIENT-2219
              .setTlsDetailsFactory(new Factory<SSLEngine, TlsDetails>() {
                @Override
                public TlsDetails create(final SSLEngine sslEngine) {
                  return new TlsDetails(sslEngine.getSession(), sslEngine.getApplicationProtocol());
                }
              })
              .build();

      final PoolingAsyncClientConnectionManager connectionManager = PoolingAsyncClientConnectionManagerBuilder
              .create()
              .setTlsStrategy(tlsStrategy)
              .setMaxConnTotal(1000)
              .setMaxConnPerRoute(1000)
              .setDefaultConnectionConfig(ConnectionConfig.custom()
                      .setTimeToLive(300, TimeUnit.SECONDS)
                      .setConnectTimeout(Timeout.ofSeconds(5))
                      .setSocketTimeout(Timeout.ofSeconds(60))
                      .build())
              .build();

      return httpClientBuilder
              .setDefaultCredentialsProvider(provider)
              .setConnectionManager(connectionManager);
    });

    final OpenSearchTransport transport = builder.build();
    return new OpenSearchClient(transport);
  }

  public static void main(String[] args) throws Exception {
    String file = "<证书保存地址>";
    OpenSearchClient client = new OSinitClientWithCA().initClientWithCA(
            Arrays.asList(new HttpHost("https","<访问域名>", 9200)),
            file, "admin", "<用户密码>");

    try {
      HealthResponse health = client.cluster().health();
      System.out.println("current cluster status is: " + health.status()); // 输出 - current cluster status is: GREEN
    } catch (Exception e) {
      e.printStackTrace();
    }
    client.shutdown();
  }

}

忽略 Https 证书连接实例

该场景适用于连接访问方式为 HTTPS 的 OpenSearch 实例，连接过程中忽略 HTTPS 证书。
示例代码如下：

import org.apache.hc.client5.http.auth.AuthScope;
import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
import org.apache.hc.client5.http.config.ConnectionConfig;
import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManager;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
import org.apache.hc.client5.http.ssl.ClientTlsStrategyBuilder;
import org.apache.hc.core5.function.Factory;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.nio.ssl.TlsStrategy;
import org.apache.hc.core5.reactor.ssl.TlsDetails;
import org.apache.hc.core5.ssl.SSLContextBuilder;
import org.apache.hc.core5.util.Timeout;
import org.opensearch.client.opensearch.OpenSearchClient;
import org.opensearch.client.opensearch.cluster.HealthResponse;
import org.opensearch.client.transport.OpenSearchTransport;
import org.opensearch.client.transport.httpclient5.ApacheHttpClient5TransportBuilder;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;
import java.util.concurrent.TimeUnit;


public class OSinitClientIgnoreCA {

  public OpenSearchClient initClientIgnoreCA(HttpHost[] hosts, String user, String password) throws Exception {

    if (hosts == null || hosts.length == 0) {
      throw new IllegalArgumentException("invalid empty hosts");
    }
    BasicCredentialsProvider provider = new BasicCredentialsProvider();
    for (HttpHost host : hosts) {
      provider.setCredentials(new AuthScope(host), new UsernamePasswordCredentials(user, password.toCharArray()));
    }

    SSLContext sslContext = new SSLContextBuilder().loadTrustMaterial(null, (x509Certificates, s) -> true).build();  // 跳过 SSL 证书校验

    final ApacheHttpClient5TransportBuilder builder = ApacheHttpClient5TransportBuilder.builder(hosts);
    builder.setHttpClientConfigCallback(httpClientBuilder -> {
      final TlsStrategy tlsStrategy = ClientTlsStrategyBuilder.create()
              .setSslContext(sslContext)
              // See https://issues.apache.org/jira/browse/HTTPCLIENT-2219
              .setTlsDetailsFactory(new Factory<SSLEngine, TlsDetails>() {
                @Override
                public TlsDetails create(final SSLEngine sslEngine) {
                  return new TlsDetails(sslEngine.getSession(), sslEngine.getApplicationProtocol());
                }
              })
              .build();

      final PoolingAsyncClientConnectionManager connectionManager = PoolingAsyncClientConnectionManagerBuilder
              .create()
              .setTlsStrategy(tlsStrategy)
              .setMaxConnTotal(1000)    //最大连接数
              .setMaxConnPerRoute(1000)  //route的最大连接数
              .setDefaultConnectionConfig(ConnectionConfig.custom()
                      .setTimeToLive(300, TimeUnit.SECONDS) //链接最大存活时间，实例重启后自动平衡负载周期
                      .setConnectTimeout(Timeout.ofSeconds(5))  //连接超时时间
                      .setSocketTimeout(Timeout.ofSeconds(60))
                      .build())
              .build();

      return httpClientBuilder
              .setDefaultCredentialsProvider(provider)
              .setConnectionManager(connectionManager);
    });

    final OpenSearchTransport transport = builder.build();
    return new OpenSearchClient(transport);
  }

  public static void main(String[] args) throws Exception {
    OpenSearchClient client = new OSinitClientIgnoreCA().initClientIgnoreCA(
            new HttpHost[]{new HttpHost("https","<访问域名>", 9200)},
            "admin", "<用户密码>");

    try {
      HealthResponse health = client.cluster().health();
      System.out.println("current cluster status is: " + health.status()); // 输出 - current cluster status is: GREEN
    } catch (Exception e) {
      e.printStackTrace();
    }
    client.shutdown();
  }

}

连接 Http 实例

该场景适用于连接访问方式为 HTTP 的 OpenSearch 实例。
示例代码如下：

import org.apache.hc.client5.http.auth.AuthScope;
import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
import org.apache.hc.client5.http.config.ConnectionConfig;
import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManager;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
import org.apache.hc.client5.http.ssl.ClientTlsStrategyBuilder;
import org.apache.hc.core5.function.Factory;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.nio.ssl.TlsStrategy;
import org.apache.hc.core5.reactor.ssl.TlsDetails;
import org.apache.hc.core5.ssl.SSLContextBuilder;
import org.apache.hc.core5.util.Timeout;
import org.opensearch.client.opensearch.OpenSearchClient;
import org.opensearch.client.opensearch.cluster.HealthResponse;
import org.opensearch.client.transport.OpenSearchTransport;
import org.opensearch.client.transport.httpclient5.ApacheHttpClient5TransportBuilder;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;
import java.util.concurrent.TimeUnit;


public class OSinitClientHttp {

  public OpenSearchClient initClientHttp(HttpHost[] hosts, String user, String password) throws Exception {

    if (hosts == null || hosts.length == 0) {
      throw new IllegalArgumentException("invalid empty hosts");
    }
    BasicCredentialsProvider provider = new BasicCredentialsProvider();
    for (HttpHost host : hosts) {
      provider.setCredentials(new AuthScope(host), new UsernamePasswordCredentials(user, password.toCharArray()));
    }

    final ApacheHttpClient5TransportBuilder builder = ApacheHttpClient5TransportBuilder.builder(hosts);
    builder.setHttpClientConfigCallback(httpClientBuilder -> {
      final PoolingAsyncClientConnectionManager connectionManager = PoolingAsyncClientConnectionManagerBuilder
              .create()
              .setMaxConnTotal(1000)    //最大连接数
              .setMaxConnPerRoute(1000)  //route的最大连接数
              .setDefaultConnectionConfig(ConnectionConfig.custom()
                      .setTimeToLive(300, TimeUnit.SECONDS) //链接最大存活时间，实例重启后自动平衡负载周期
                      .setConnectTimeout(Timeout.ofSeconds(5))  // 连接超时时间
                      .setSocketTimeout(Timeout.ofSeconds(60))
                      .build())
              .build();
      return httpClientBuilder
              .setDefaultCredentialsProvider(provider)
              .setConnectionManager(connectionManager);
    });

    final OpenSearchTransport transport = builder.build();
    return new OpenSearchClient(transport);
  }

  public static void main(String[] args) throws Exception {
    OpenSearchClient client = new OSinitClientHttp().initClientHttp(
            new HttpHost[]{new HttpHost("https","<访问域名>", 9200)},
            "admin", "<用户密码>");

    try {
      HealthResponse health = client.cluster().health();
      System.out.println("current cluster status is: " + health.status()); // 输出 - current cluster status is: GREEN
    } catch (Exception e) {
      e.printStackTrace();
    }
    client.shutdown();
  }

}

创建索引

执行以下代码，可以向目标索引中写入文档。

// 最小化创建索引
String index = "sample-index";
CreateIndexRequest createIndexRequest = new CreateIndexRequest.Builder().index(index).build();
client.indices().create(createIndexRequest);
IndexSettings indexSettings = new IndexSettings.Builder().autoExpandReplicas("0-all").build();
PutIndicesSettingsRequest putIndicesSettingsRequest = new PutIndicesSettingsRequest.Builder().index(index).value(indexSettings).build();
client.indices().putSettings(putIndicesSettingsRequest);


// 创建disann 向量索引
String index = "sample-index";
final KnnVectorProperty nameVector = KnnVectorProperty.of(
        v -> v.dimension(4)
                .method(m -> m.spaceType("cosinesimil")
                  .engine("diskann")
                  .name("diskann")
                  .parameters("L", JsonData.of(30))
                  .parameters("R", JsonData.of(32))
                )
        );


client.indices().create(ci ->  ci.index(index)
        .mappings(
                builder -> builder.properties(
                        "firstName", p -> p.text(t -> t.analyzer("ik_smart"))
                ).properties("nameVector", p -> p.knnVector(nameVector))
        )
        .settings(s -> s.index(indexSetting -> indexSetting.knn(true))));

// 更新索引配置
client.indices().putSettings(ps -> ps.index(index)
        .settings(s -> s.autoExpandReplicas("0-all"))
);

增删改查

这里只展示向量和文本基本的增删改查样例， 其他高级特性如利用ingest pipeline无感写入向量等，参考最佳实践其他文档。

文档数据

增删改查所有的文档结构基于以下类。

class IndexData {
  private String firstName;
  private Float[] nameVector;
  public IndexData() {

  }
  public IndexData(String firstName, Float[] nameVector) {
    this.firstName = firstName;
    this.nameVector = nameVector;
  }

  public void setFirstName(String firstName) {
    this.firstName = firstName;
  }

  public void setNameVector(Float[] nameVector) {
    this.nameVector = nameVector;
  }

  public String getFirstName() {
    return this.firstName;
  }

  public Float[] getNameVector() {
    return this.nameVector;
  }
}

写入文档

IndexData indexData = new IndexData( "云搜索", new Float[]{ 1.0f,1.0f,1.0f,1.0f});
client.index(ib -> ib.index(index).id("1").document(indexData));
client.indices().refresh(r -> r.index(index));

搜索文档

// 文本搜索
SearchResponse<IndexData> search_res = client.search(
  r -> r.query(
    q -> q.match(
      match -> match.field("firstName")
              .query(f -> f.stringValue("云搜索"))
              .analyzer("ik_smart")
    )
  )
  , IndexData.class);

System.out.println(search_res.hits().hits().get(0).source().getFirstName());

// 向量搜索
SearchResponse<IndexData> vector_res = client.search(
  r -> r.query(
    q -> q.knn(
      knn -> knn.field("nameVector")
              .k(10)
              .vector(new float[]{ 1.0f, 1.0f, 1.0f, 1.0f})
    )
  )
, IndexData.class);
System.out.println(vector_res.hits().hits().get(0).source().getFirstName());

// 使用原始的json 搜索
String json_query = "{\"match\":{ \"firstName\": \"云搜索\"}}";
String encodedJSON = Base64.getEncoder().encodeToString(json_query.getBytes());

SearchResponse<IndexData> search_by_json = client.search(
        r -> r.query(
                q -> q.wrapper(m -> m.query(encodedJSON))),
        IndexData.class
);
System.out.println(search_by_json.hits().hits().get(0).source().getFirstName());


//class 参数传递 com.fasterxml.jackson.databind.node.ObjectNode 可以获取原始json

更新文档

//进行数据更新
IndexData updateData = new IndexData();
updateData.setFirstName("OpenSearch");
client.update(r -> r.id("1").doc(updateData).index(index),IndexData.class);


//刷盘
client.indices().refresh(r -> r.index(index));

//查询数据是否更新成功
GetResponse<IndexData> getRes = client.get(r -> r.id("1").index(index), IndexData.class);
System.out.println(getRes.source().getFirstName());

删除文档

client.delete(b -> b.index(index).id("1"));

完整样例

import org.apache.hc.client5.http.auth.AuthScope;
import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
import org.apache.hc.client5.http.config.ConnectionConfig;
import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManager;
import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
import org.apache.hc.client5.http.ssl.ClientTlsStrategyBuilder;
import org.apache.hc.core5.function.Factory;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.nio.ssl.TlsStrategy;
import org.apache.hc.core5.reactor.ssl.TlsDetails;
import org.apache.hc.core5.ssl.SSLContextBuilder;
import org.apache.hc.core5.util.Timeout;
import org.opensearch.client.json.JsonData;
import org.opensearch.client.opensearch.OpenSearchClient;
import org.opensearch.client.opensearch._types.FieldValue;
import org.opensearch.client.opensearch._types.mapping.KnnVectorProperty;
import org.opensearch.client.opensearch._types.mapping.Property;
import org.opensearch.client.opensearch._types.mapping.TextProperty;
import org.opensearch.client.opensearch._types.mapping.TypeMapping;
import org.opensearch.client.opensearch.cluster.HealthResponse;
import org.opensearch.client.opensearch.core.*;
import org.opensearch.client.opensearch.indices.CreateIndexRequest;
import org.opensearch.client.opensearch.indices.IndexSettings;
import org.opensearch.client.opensearch.indices.PutIndicesSettingsRequest;
import org.opensearch.client.opensearch.indices.RefreshRequest;
import org.opensearch.client.transport.OpenSearchTransport;
import org.opensearch.client.transport.httpclient5.ApacheHttpClient5TransportBuilder;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;
import java.util.Base64;
import java.util.concurrent.TimeUnit;


public class OSinitClientTest {

  public OpenSearchClient initClientIgnoreCA(HttpHost[] hosts, String user, String password) throws Exception {

    if (hosts == null || hosts.length == 0) {
      throw new IllegalArgumentException("invalid empty hosts");
    }
    BasicCredentialsProvider provider = new BasicCredentialsProvider();
    for (HttpHost host : hosts) {
      provider.setCredentials(new AuthScope(host), new UsernamePasswordCredentials(user, password.toCharArray()));
    }

    SSLContext sslContext = new SSLContextBuilder().loadTrustMaterial(null, (x509Certificates, s) -> true).build();  // 跳过 SSL 证书校验

    final ApacheHttpClient5TransportBuilder builder = ApacheHttpClient5TransportBuilder.builder(hosts);
    builder.setHttpClientConfigCallback(httpClientBuilder -> {
      final TlsStrategy tlsStrategy = ClientTlsStrategyBuilder.create()
              .setSslContext(sslContext)
              // See https://issues.apache.org/jira/browse/HTTPCLIENT-2219
              .setTlsDetailsFactory(new Factory<SSLEngine, TlsDetails>() {
                @Override
                public TlsDetails create(final SSLEngine sslEngine) {
                  return new TlsDetails(sslEngine.getSession(), sslEngine.getApplicationProtocol());
                }
              })
              .build();

      final PoolingAsyncClientConnectionManager connectionManager = PoolingAsyncClientConnectionManagerBuilder
              .create()
              .setTlsStrategy(tlsStrategy)
              .setMaxConnTotal(1000)    //最大连接数
              .setMaxConnPerRoute(1000)  //route的最大连接数
              .setDefaultConnectionConfig(ConnectionConfig.custom()
                      .setTimeToLive(300, TimeUnit.SECONDS) //链接最大存活时间，实例重启后自动平衡负载周期
                      .setConnectTimeout(Timeout.ofSeconds(5))  // 连接超时时间
                      .setSocketTimeout(Timeout.ofSeconds(60))
                      .build())
              .build();

      return httpClientBuilder
              .setDefaultCredentialsProvider(provider)
              .setConnectionManager(connectionManager);
    });

    final OpenSearchTransport transport = builder.build();
    return new OpenSearchClient(transport);
  }

  public static void main(String[] args) throws Exception {
    /**
     * 连接实例
     */
    OpenSearchClient client = new OSinitClientTest().initClientIgnoreCA(
            new HttpHost[]{new HttpHost("<https|http>","<接入点地址>", 9200)},
            "<账号>", "<密码>");

    try {
      HealthResponse health = client.cluster().health();

      System.out.println("current cluster status is: " + health.status()); // 输出 - current cluster status is: GREEN
    } catch (Exception e) {
      e.printStackTrace();
    }

    /**
     * 索引创建，构建一个带有vector和text的索引
     */
    String index = "sample-index";
    final KnnVectorProperty nameVector = KnnVectorProperty.of(
            v -> v.dimension(4)
                    .method(m -> m.spaceType("cosinesimil")
                      .engine("diskann")
                      .name("diskann")
                      .parameters("L", JsonData.of(30))
                      .parameters("R", JsonData.of(32))
                    )
            );

    client.indices().create(ci ->  ci.index(index)
            .mappings(
                    builder -> builder.properties(
                            "firstName", p -> p.text(t -> t.analyzer("ik_smart"))
                    ).properties("nameVector", p -> p.knnVector(nameVector))
            )
            .settings(s -> s.index(indexSetting -> indexSetting.knn(true))));

    /**
     * 更新索引配置
     */
    client.indices().putSettings(ps -> ps.index(index)
            .settings(s -> s.autoExpandReplicas("0-all"))
    );


    /**
     * 写入文档
     */
    IndexData indexData = new IndexData( "云搜索", new Float[]{ 1.0f,1.0f,1.0f,1.0f});
    client.index(ib -> ib.index(index).id("1").document(indexData));

    // 刷新索引保证文档立即可见
    client.indices().refresh(r -> r.index(index));


    /**
     * 用json进行搜索
     */
    String json_query = "{\"match\":{ \"firstName\": \"云搜索\"}}";
    String encodedJSON = Base64.getEncoder().encodeToString(json_query.getBytes());

    SearchResponse<IndexData> search_by_json = client.search(
            r -> r.query(
                    q -> q.wrapper(m -> m.query(encodedJSON))),
            IndexData.class
    );
    System.out.println(search_by_json.hits().hits().get(0).source().getFirstName());


    /**
     * 进行全文搜索
     */
    SearchResponse<IndexData> search_res = client.search(
      r -> r.query(
        q -> q.match(
          match -> match.field("firstName")
                  .query(f -> f.stringValue("云搜索"))
                  .analyzer("ik_smart")
        )
      )
      , IndexData.class);


    System.out.println(search_res.hits().hits().get(0).source().getFirstName());

    /**
     * 进行向量搜索
     */
    SearchResponse<IndexData> vector_res = client.search(
      r -> r.query(
        q -> q.knn(
          knn -> knn.field("nameVector")
                  .k(10)
                  .vector(new float[]{ 1.0f, 1.0f, 1.0f, 1.0f})
        )
      )
    , IndexData.class);
    System.out.println(vector_res.hits().hits().get(0).source().getFirstName());

    /**
     * 更新文档
     */
    IndexData updateData = new IndexData();
    updateData.setFirstName("OpenSearch");
    client.update(r -> r.id("1").doc(updateData).index(index),IndexData.class);

    //刷新索引保证文档立即可见
    client.indices().refresh(r -> r.index(index));

    //确定更新结果
    GetResponse<IndexData> getRes = client.get(r -> r.id("1").index(index), IndexData.class);
    System.out.println(getRes.source().getFirstName());


    /**
     * 删除文档
     */
    client.delete(b -> b.index(index).id("1"));

    /**
     * 删除索引
     */
    client.indices().delete( r -> r.index(index));
    client.shutdown();
  }

}

class IndexData {
  private String firstName;
  private Float[] nameVector;
  public IndexData() {

  }
  public IndexData(String firstName, Float[] nameVector) {
    this.firstName = firstName;
    this.nameVector = nameVector;
  }

  public void setFirstName(String firstName) {
    this.firstName = firstName;
  }

  public void setNameVector(Float[] nameVector) {
    this.nameVector = nameVector;
  }

  public String getFirstName() {
    return this.firstName;
  }

  public Float[] getNameVector() {
    return this.nameVector;
  }
}