Volatile - Marks the JVM backing field of the annotated property as volatile, meaning that writes to this field are immediately made visible to other threads.

MultithreadedDataHolder.kt

/**
 * We have a data holder class called [MultithreadedDataHolder] that hold some data
 * which will be used by different clients from different [Thread]s. Multiple clients
 * can access the same object simultaneously.
 *
 * Any object that is annotated with Annotation [Volatile] make sure that the changes
 * made in one thread are immediately reflect in other thread.
 */
object MultithreadedDataHolder {
    /*It's guaranteed that all reader threads will see the updated value of the
    volatile variable once the write operation is completed, without volatile
    keyword different reader thread may see different values.*/
    @Volatile
    var someData: Any? = null
        private set

    fun updateData(data: Any) {
        this.someData = data
        println("Data stored...")
    }
}