回复：introduce retryer for async function

[GabryWu]

I created one 
PR: https://github.com/apache/incubator-dolphinscheduler/pull/2679




------------------ 原始邮件 ------------------
发件人:&nbsp;"GabryWu"<wu_shao_...@qq.com&gt;;
发送时间:&nbsp;2020年5月11日(星期一) 中午1:01
收件人:&nbsp;"dev"<dev@dolphinscheduler.apache.org&gt;;

主题:&nbsp;introduce retryer for async function



Now, dolphin already refactor worker ,and netty is being used.
It can be predicted that async method will be more and more used ,and function 
retryer is necessary .
If we simply call function twice or more , it's ugly and beyonds understanding


So I suggest we introduce a retryer class ,for example 
https://github.com/rholder/guava-retrying