elasticsearch 6.x RestHighLevelClient使用

备注：elasticsearch6.x以后一个index只能存在一个type。以下代码仅供参考，涉及的参数需要根据使用场景进行修改。

<dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>6.3.2</version>
</dependency>
<dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version6.3.2</version>
</dependency>

//初始化client
RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(
                    new HttpHost("127.0.0.1", 9200, "http")));

//删除索引 
public boolean deleteIndex(String index){
         DeleteIndexRequest request = new DeleteIndexRequest(index);  
         request.indicesOptions(IndicesOptions.lenientExpandOpen());
         DeleteIndexResponse = client.indices().delete(request);
         return deleteIndexResponse.isAcknowledged();
         }

//创建索引  
 public boolean createIndex(String index,String alias,int
 numberOfShards,int numberOfRelicas){ 
         CreateIndexRequest request = new CreateIndexRequest(index); 
         request.settings(Settings.builder()
             .put("index.number_of_shards", numberOfShards)
             .put("index.number_of_replicas", numberOfRelicas)
         ); 
         //如果不需要指定字段属性可以忽略以下mapping设置，新增文档后会自动创建mapping
         request.mapping("data",
             "  {\n" +
                 "    \""+type+"\": {\n" +
                 "      \"properties\": {\n" +
                        需要的设计的字段属性+
                 "      }\n" +
                 "    }\n" +
                 "  }",
             XContentType.JSON); 
             //设置别名
         if(alias != null && !alias.equals("")){
             request.alias(
                 new Alias(alias)
             );
         }  
         CreateIndexResponse createIndexResponse = client.indices().create(request);  
         return createIndexResponse.isAcknowledged();
     } 

//判断索引是否存在    
 public boolean isIndexExists(String index){ 
         GetIndexRequest request = new GetIndexRequest();
         request.indices(index);
         request.local(false);
         request.humanReadable(true); 
         boolean exists  = client.indices().exists(request) ;
        return exists;
     }