java - 关于实际项目中，对象关联通常是单向还是双向，各有什么优缺点 ？
关于实际项目中，对象关联通常是单向还是双向，各有什么优缺点 ？
大家讲道理2017-04-18 10:27:55
Personally, I think this depends on the usage scenario
It is irreversible access, hierarchical relationship, and superior data storage
Can access each other, easy to obtain data
