Elasticsearch6.x和7.x的区别

1、查找方面的区别

在增删改方面，6.x和7.x是一样的，在查找方面（分为普通查找和有高亮的查找），6.x和7.x有区别。

在7.x的es中：

org.springframework.data.elasticsearch.core.SearchResultMapper没有这个类了
org.springframework.data.elasticsearch.core.ElasticsearchTemplate 已废弃
org.springframework.data.elasticsearch.repository.ElasticsearchRepository<T,

ID>.search(org.springframework.data.elasticsearch.core.query.Query) 已废弃

于是在普通查找和带高亮的查找方面，es6.x和7.x不一样。

2、配置文件的区别

es6.x application.properties

properties 复制代码

# 旧版本以spring.data.elasticsearch.开头;访问地址配置不用声明访问协议,监听es的tcp端口
# 7.x已经弃用了
spring.data.elasticsearch.cluster-name=my-application
spring.data.elasticsearch.cluster-nodes=127.0.0.1:9300

es7.x application.properties

properties 复制代码

# 新版本以spring.elasticsearch.rest.开头;访问地址配置需要声明访问协议,直接监听es访问端口
spring.elasticsearch.rest.uris=http://localhost:9200

3、Document注解的type属性

es6.x 有type = "_doc"

java 复制代码

@Document(indexName = "discusspost", type = "_doc", shards = 6, replicas = 3)
public class DiscussPost {

}

es7.x 无type = "_doc"

java 复制代码

@Document(indexName = "discusspost", shards = 6, replicas = 3)
public class DiscussPost {

}

4、Elasticsearch Clients的区别

下方内容来自官方文档：

https://docs.spring.io/spring-data/elasticsearch/docs/4.0.1.RELEASE/reference/html/#reference

ES6.x：Transport Client

java 复制代码

@Configuration
public class TransportClientConfig extends ElasticsearchConfigurationSupport {

    @Bean
    public Client elasticsearchClient() throws UnknownHostException {
        Settings settings = Settings.builder().put("cluster.name", "elasticsearch").build();        
        TransportClient client = new PreBuiltTransportClient(settings);
        client.addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300)); 
        return client;
    }

    @Bean(name = { "elasticsearchOperations", "elasticsearchTemplate" })
    public ElasticsearchTemplate elasticsearchTemplate() throws UnknownHostException {
        return new ElasticsearchTemplate(elasticsearchClient());
    }
}

ES7.x：High Level REST Client

java 复制代码

@Configuration
public class RestClientConfig extends AbstractElasticsearchConfiguration {

    @Override
    @Bean
    public RestHighLevelClient elasticsearchClient() {

        final ClientConfiguration clientConfiguration = ClientConfiguration.builder()  
            .connectedTo("localhost:9200")
            .build();

        return RestClients.create(clientConfiguration).rest();                         
    }
}