loom ui example

testLoom.kt

@file:Suppress("JAVA_MODULE_DOES_NOT_EXPORT_PACKAGE")

import jdk.internal.vm.Continuation
import jdk.internal.vm.ContinuationScope
import javax.swing.SwingUtilities

class UILoomScope(
    private val continuationScope: ContinuationScope,
    private val continuation: Continuation
) {
    fun yield(actionNotInUIThread: () -> Unit = { }) {
        Thread.ofVirtual().name("NotUI").start() {
            actionNotInUIThread()
            SwingUtilities.invokeLater {
                continuation.run()
            }
        }
        Continuation.yield(continuationScope)
    }
}

class UILoomAction(private val action: UILoomScope.() -> Unit) {
    private val continuationScope = ContinuationScope("loom action")
    private val continuation = Continuation(continuationScope) {
        runAction()
    }
    private val scope = UILoomScope(continuationScope, continuation)



    fun run() {
        SwingUtilities.invokeLater {
            continuation.run()
        }
    }

    private fun runAction() {
        scope.action()
    }
}



fun main() {
    val action = UILoomAction() {
        println("Action 1 in Thread: ${Thread.currentThread().name}")
        yield {
            println("Not UI action in Thread: ${Thread.currentThread().name}")
        }
        println("Action 2 in Thread: ${Thread.currentThread().name}")
    }
    action.run()
}

Run with --enable-preview --add-exports java.base/jdk.internal.vm=ALL-UNNAMED JVM arguments