Add a virtual-thread backed @ManagedAsyncExecutor

service/src/main/java/org/whispersystems/textsecuregcm/util/VirtualExecutorServiceProvider.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2024 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+package org.whispersystems.textsecuregcm.util;
+
+import java.util.List;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import org.glassfish.jersey.server.ManagedAsyncExecutor;
+import org.glassfish.jersey.spi.ExecutorServiceProvider;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+@ManagedAsyncExecutor
+public class VirtualExecutorServiceProvider implements ExecutorServiceProvider {
+  private static final Logger logger = LoggerFactory.getLogger(VirtualExecutorServiceProvider.class);
+
+
+  /**
+   * Default thread pool executor termination timeout in milliseconds.
+   */
+  public static final int TERMINATION_TIMEOUT = 5000;
+  private final String virtualThreadNamePrefix;
+
+  public VirtualExecutorServiceProvider(final String virtualThreadNamePrefix) {
+    this.virtualThreadNamePrefix = virtualThreadNamePrefix;
+  }
+
+
+  @Override
+  public ExecutorService getExecutorService() {
+    logger.info("Creating executor service with virtual thread per task");
+    return Executors.newThreadPerTaskExecutor(Thread.ofVirtual().name(virtualThreadNamePrefix, 0).factory());
+  }
+
+  @Override
+  public void dispose(final ExecutorService executorService) {
+    logger.info("Shutting down virtual thread pool executor");
+
+    executorService.shutdown();
+    boolean terminated = false;
+    try {
+      terminated = executorService.awaitTermination(TERMINATION_TIMEOUT, TimeUnit.MILLISECONDS);
+    } catch (InterruptedException e) {
+      Thread.currentThread().interrupt();
+    }
+
+    if (!terminated) {
+      // virtual thread per task executor has no queue, so shouldn't have any un-run tasks
+      final List<Runnable> unrunTasks = executorService.shutdownNow();
+      logger.info("Force terminated executor with {} un-run tasks", unrunTasks.size());
+    }
+  }
+}