code: public <T> T getDocumentByPath(String path,Class<T> beanType) throws ElasticSearchException{
  		try {
  			SearchHit searchResult = this.client.executeRequest(path,null,   new GetDocumentResponseHandler( beanType),ClientUtil.HTTP_GET);
  			return ResultUtil.buildObject(searchResult, beanType);
  		}
  		catch(ElasticSearchException e){
  			return ResultUtil.hand404HttpRuntimeException(e,beanType,ResultUtil.OPERTYPE_getDocument);
  		}
  	}
docs: 获取json格式文档
  https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-get.html
  @param path twitter/_doc/0
  twitter/_doc/0?_source=false
  twitter/_doc/0?_source_include=*.id&_source_exclude=entities
  twitter/_doc/0?_source=*.id,retweeted
  twitter/_doc/1?stored_fields=tags,counter
  twitter/_doc/2?routing=user1&stored_fields=tags,counter
  twitter/_doc/1/_source
  GET twitter/_doc/2?routing=user1
  
  @param path
  @return
  @throws ElasticSearchException