案例对象和对象的区别 [英] Difference between case object and object

问题描述

scala 中 case 对象和对象有什么区别吗?

Is there any difference between case object and object in scala?

推荐答案

案例类与常规类的不同之处在于:

Case classes differ from regular classes in that they get:

1. 模式匹配支持
2. equals 和 hashCode 的默认实现
3. 序列化的默认实现
4. toString 的更漂亮的默认实现，以及
5. 他们从scala.Product 自动继承的少量功能.

1. pattern matching support
2. default implementations of equals and hashCode
3. default implementations of serialization
4. a prettier default implementation of toString, and
5. the small amount of functionality that they get from automatically inheriting from scala.Product.

模式匹配、equals 和 hashCode 对单例并不重要(除非你做一些真正退化的事情)，所以你几乎只是获得序列化，一个很好的 toString，以及一些你需要的方法可能永远不会用了.

Pattern matching, equals and hashCode don't matter much for singletons (unless you do something really degenerate), so you're pretty much just getting serialization, a nice toString, and some methods you probably won't ever use.

这篇关于案例对象和对象的区别的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！