Java操作elasticSearch整合SpringBoot

针对elasticSearch不同端口操作客户端API：

1）、9300：TCP （es集群通讯9300）

· spring-data-elasticsearch:transport-api.jar；

· springboot 版本不同， transport-api.jar 不同，不能适配 es 版本

· 官网 es的版本：7.x 已经不建议使用，8 以后就要废弃

2）、9200：HTTP

· JestClient：非官方，更新慢

· RestTemplate：模拟发 HTTP 请求，ES 很多操作需要自己封装，麻烦

· HttpClient：同上 ▷ Elasticsearch-Rest-Client：官方 RestClient，封装了 ES 操作，API 层次分明，上手简单 最终选择 Elasticsearch-Rest-Client（elasticsearch-rest-high-level-client） https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high.html

▷Elasticsearch-Rest-Client（elasticsearch-rest-high-level-client）

整合SpringBoot

版本说明：elasticSearch版本 kibana版本 Elasticsearch-Rest-Client版本 请保持一致

<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.4.2</version>
</dependency>
配置： 容器中导入RestHighLevelClient 操作以及加密鉴权
**
 * 1.导入依赖
 * 2.容器中导入RestHighLevelClient 操作9200
 */
//注解配置启动容器自动执行
@Configuration
public class ElasticSearchConfig {
	
    //常亮配置项 在调用es操作的时候直接引用这个常量
    public static final RequestOptions COMMON_OPTIONS;
    static {
        RequestOptions.Builder builder = RequestOptions.DEFAULT.toBuilder();
        //加密内容
//        builder.addHeader("Authorization","Bearer"+TOKEN );
//        builder.setHttpAsyncResponseConsumerFactory(
//                new HttpAsyncResponseConsumerFactory
//                        .HeapBufferedResponseConsumerFactory(30*1024*1024*1024)
//        );
        COMMON_OPTIONS = builder.build();
    }


    //容器中引入client 调用es服务时，用这个client请求
    @Bean
    public RestHighLevelClient esRestClient(){
          //多个es的写法
//        RestHighLevelClient client = new RestHighLevelClient(
//                RestClient.builder(
//                        //多个es     new HttpHost("192.168.31.120",9200,"http"),
//                        new HttpHost("192.168.31.125",9200,"http")));
//        return client;
        RestClientBuilder builder = null;
        builder = RestClient.builder(new HttpHost("192.168.31.125",9200,"http"));
        RestHighLevelClient client = new RestHighLevelClient(builder);
        return client;
    }
}
单元测试
@RunWith(SpringRunner.class)
@SpringBootTest
public class GulimallSearchApplicationTests {

	@Autowired
	private RestHighLevelClient client;
    	@Test
	public void contextLoads() {
		System.out.println(client);
	}
}
2021-11-05 15:44:39.332  INFO 2108 --- [           main] c.a.g.s.GulimallSearchApplicationTests   : Started GulimallSearchApplicationTests in 19.746 seconds (JVM running for 21.598)
org.elasticsearch.client.RestHighLevelClient@342e690b
2021-11-05 15:44:39.690  INFO 2108 --- [       Thread-9] o.s.s.concurrent.ThreadPoolTaskExecutor  : Shutting down ExecutorService 'applicationTaskExecutor'

Process finished with exit code 0

看到client的打印信息：org.elasticsearch.client.RestHighLevelClient@342e690b

整合成功