loom

1. download Loom Early-Access Builds

   open https://jdk.java.net/loom/ download linux tar.gz

   decompression to .jdks/jdk-16

2. cat LoomApp.java

   import java.util.concurrent.Executors;
   import java.util.concurrent.Callable;
   import java.util.List;
   import java.util.concurrent.CompletableFuture;
   import java.time.Instant;
   import java.util.concurrent.TimeUnit;
   public class LoomApp{
   
       public static void main (String [] args) throws Exception{
           var thread = Thread.startVirtualThread(() -> System.out.println("virtualthread Hello"));
           thread.join();
   
           var thread1 = Thread.builder().virtual().task(() -> System.out.println("virtual task hello")).build();
           var thread2 = Thread.builder()
               .virtual()
               .name("bob")
               .task(() -> System.out.println("virtual name task I'm Bob!"))
               .start();
   
           var factory = Thread.builder().virtual().name("worker", 0).factory();
   
           try(var executor = Executors.newVirtualThreadExecutor()){
               executor.execute(() -> System.out.println("Hello"));
               executor.execute(() -> System.out.println("Hi"));
           }
   
           try(var executor = Executors.newVirtualThreadExecutor()){
               Callable<String> task1 = () -> "invokeAny foo";
               Callable<String> task2 = () -> "invokeAny bar";
               Callable<String> task3 = () -> "invokeAny baz";
   
               var result = executor.invokeAny(List.of(task1, task2, task3));
           }
   
           try(var executor = Executors.newVirtualThreadExecutor()){
               Callable<String> task1 = () -> "completable future foo";
               Callable<String> task2 = () -> "completable future bar";
               Callable<String> task3 = () -> "completable future baz";
   
               var cfs = executor.submitTasks(List.of(task1, task2, task3));
   
               CompletableFuture.completed(cfs)
                   .map(CompletableFuture::join)
                   .forEach(System.out::println);
           }
   
           var seconds = 3;
           var deadline = Instant.now().plusSeconds(seconds) ;
   
           try(var executor = Executors.newVirtualThreadExecutor().withDeadline(deadline)){
               Callable<String> task1 = () -> "deadline foo";
               Callable<String> task2 = () -> "deadline bar";
               Callable<String> task3 = () -> "deadline baz";
               Callable<String> task4 = () -> {
                   var sleepSeconds = seconds - 1;
                   TimeUnit.SECONDS.sleep(sleepSeconds);
                   return "deadline task4 by sleep " + sleepSeconds + " seconds";
               };
   
               var cfs = executor.submitTasks(List.of(task1, task2, task3, task4));
   
               CompletableFuture.completed(cfs)
                   .map(CompletableFuture::join)
                   .forEach(System.out::println);
   
           }
   
       }
   }

3. run LoomApp.java

   .jdks/jdk-16/bin/java LoomApp.java