将List 编码为plain String并将其解码回来的最简单方法是什么？

I think I've come across this requirement for a dozen times. But I could never find a satisfying solution. For instance, there are a collection of string which I want to serialize (to disk or through network) through a channel where only plain string is allowed. I almost always end up using "split" and "join" with ridiculous separator like I think I've come across this requirement for a