public Map<String,String> getFileInfo(String file) throws Exception{
		HttpAction("HEAD", "/"+bucketname+file);
		if(_file_type == null)return null;
		Map<String,String> mp=new HashMap<String, String>();
		mp.put("type", _file_type);
		mp.put("size", _file_size);
		mp.put("date", _file_date);
		return mp;
	}