Kotlin is known primarily as a drop-in replacement for Java, but it gets rid of a well-known Java construct: the static keyword. Instead, that class-level functionality is offered mainly by companion objects.
What is wrong with static methods and fields that companion objects provide a better alternative to? I'm confused about the rationale, and couldn't find any explanation in the documentation.
Best Answer
Scala also replaces class level declarations with a 'Singleton' object. The main advantage of this is that everything is an object. In Java, static members are treated very differently than object members. This means that you can't do things like implementing an interface or putting your class 'instance' into a map or pass it as a parameter to a method that takes Object. Companion objects allow for these things. That's the advantage.