Why Do I Want to Use Kotlin?

• Kotlin became the preferred language on Android platform in Google I/O 2019.
  • Got official support in 2017.
• Null Safety
  • We have to write a lot of null checks if you use Java for Android development.
  • Using Kotlin safe call operator is a nice way to solve this problem.
    • bob?.department?.head?.name
• Sealed Class
  • This one is EXTREMELY useful, and we use it frequently for UI states.
• Data Class
• Extensions
• Concise Code
  • Less code means less bugs. I mean... in general cases. 😏
• Kotlin Tooling and Android Supports
  • ViewModel
  • KTX
  • IDE supports
  • Many libs are written in Kotlin.
  • more...

How Did We Migrate from Java to Kotlin?

There are some steps that we do the migration...

1. We started from models and value objects

   1. Convert them into data classes

2. Convert files from Java to Kotlin?

   • You may try this one, but do not expect it will work perfectly and magically.
   • IDE is your teacher. 📓

   

3. Dealing with Double bang operators !!

   1. Some platform types !
   2. Or you might want to use safe call operator ?

4. Convert tests into Kotlin classes

   1. Use MockK to refactor tests.

5. Refactoring other classes in model layer

   1. For example, classes like Repository or UseCase.

6. Refactoring presentation layer

   1. It might contains Presenter or ViewModel

7. Refactoring View

8. If you are using RxJava, you can consider using Flow instead.

   • RxJava Migration Lib

Problems