You can configure your IDE to warn of incorrect usage, and you can configure your compiler to flag warnings as errors. That will catch a lot of potential proble

You can configure your IDE to warn of incorrect usage, and you can configure your compiler to flag warnings as errors. That will catch a lot of potential problems at compile time. It’s not perfect but it can be lot better than nothing. Java annotations are better than Optional when you’re interoperating with Kotlin code, such as when you’re partway through converting a large codebase to Kotlin.