In Kotlin, there is no static methods, but we can use companion object which works the same as static methods.
For example, a class:
package com.rsk import java.security.Provider import java.security.Security class Providers { // similar as static companion object { fun getProviders(): List<Provider> { val providers = Security.getProviders(); val listOfProviders: List<Provider> = providers.asList() return listOfProviders } } fun getProviders(): List<Provider> { val providers = Security.getProviders(); val listOfProviders: List<Provider> = providers.asList() return listOfProviders } }
You notice there are two functions called ‘getProviders‘, the first one is inside companion object.
The companion is singelton.
Usage:
val providers = Security.getProviders();
For the second ‘getProviders‘, usage:
val providers = Providers()
val allProviders = providers.getAllProviders()
As you can see, using companion object is musch cleaner way to write the code
[Kotlin] companion object == static method
原文：https://www.cnblogs.com/Answer1215/p/13822202.html