RestHighLevelClient判断index是否存在

判断Index是否存在版本以6.4.2为准，6.2.1api不一样

    public boolean indexExists(String indexName) {             GetIndexRequest request = new GetIndexRequest();             request.indices(indexName);             try {                 return rhlClient.indices().exists(request, RequestOptions.DEFAULT);             } catch (IOException e) {                 e.printStackTrace();                 return false;             }         }

6.2.1api使用以下方法，通过异常捕获判断es_not_found_exception

public boolean isExistIndex(String indexName){      OpenIndexRequest openIndexRequest = new OpenIndexRequest(indexName);     /*IndicesExistsRequest request = new IndicesExistsRequest(indexName);      GetIndexRequest request = new GetIndexRequest();     org.elasticsearch.client.Client Client=client;     IndicesExistsResponse response = Client.admin().indices().exists(request).actionGet();     if (response.isExists()) {         return true;     }     return false;*/      try {           client.indices().open(openIndexRequest);           return true;      }catch (ElasticsearchException e) {          return false;      }catch (Exception e) {         return false;     }  }