Combine Java with Kotlin in Android [closed]

Question

I am slightly moving from Java to Kotlin in android app development, but there are some cases where I don't want to code in Kotlin and want those particular cases be written in Java:

• It is effort-saving that Kotlin removes extra usage of findViewByIds
• I know that it is now null-safety which oppositely Java always triggered with NullPointerException
• Lambda expressions are also provided and many other features.

But still, some of my codes cannot be written in Kotlin such as static members or non-primitive fields.

Kotlin annotations actually can replace those static members. But love some coding features of Java and dont want to leave that.

My question is can I combine Java and Kotlin together?

Answer 1

If your question is can you use kotlin files in java files and vice versa then the answer is yes.

If you are asking if you can use kotlin syntax in java files and vice versa then the answer is no.

To use kotlin code in a java class you are simply using the class like any other java class

Answer 2

You can have in your project Java and Kotlin Class and Activities.

The same Class can't have Java and Kotlin. You can convert a Java file to Kotlin with Ctrl+Alt+Shift+K or just double tap SHIFT and search for Convert Java to Kotlin