code: public <T> T  sqlObject(Class<T> beanType,  String entity ) throws ElasticSearchException {
  		SQLRestResponse result = this.client.executeRequest("/_xpack/sql",entity,   new SQLRestResponseHandler());
  		return ResultUtil.buildSQLObject(result,beanType);
  	}
docs: 发送es restful sql请求/_xpack/sql，获取返回值，返回值类型由beanType决定
  @param beanType
  @param entity
  
  @param <T>
  @return
  @throws ElasticSearchException