update: warning suppression on Any

[danil-pavlov]

This PR updates the workaround for wait() and notify() on references of type Any with error-suppression annotation (KT-81586)

[KvanTTT]

I'd change the example to something more realistic:

import java.util.LinkedList

class SimpleBlockingQueue<T>(private val capacity: Int) {
    private val queue = LinkedList<T>()

    // We use java.lang.Object specifically to access wait() and notify()
    // In Kotlin, the standard 'Any' type does not expose these methods.
    @Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
    private val lock = Object()

    fun put(item: T) {
        synchronized(lock) {
            while (queue.size >= capacity) {
                lock.wait()
            }
            queue.add(item)
            println("Produced: $item")

            lock.notifyAll()
        }
    }

    fun take(): T {
        synchronized(lock) {
            while (queue.isEmpty()) {
                lock.wait()
            }
            val item = queue.removeFirst()
            println("Consumed: $item")

            lock.notifyAll()
            return item
        }
    }
}

Or just use the single-line code snippet:

@Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
(foo as java.lang.Object).wait()

The code from your example also causes a dead lock: the execution being frozen completely because there is no notify call.

[danil-pavlov]

A real-life example is definitely better for the docs, thank you for the suggestion!