Fix missing class

core/src/main/java21/com/github/games647/fastlogin/core/scheduler/AsyncScheduler.java

@@ -0,0 +1,78 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015-2024 games647 and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.github.games647.fastlogin.core.scheduler;
+
+import org.slf4j.Logger;
+
+import java.time.Duration;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
+/**
+ * This limits the number of threads that are used at maximum. Thread creation can be very heavy for the CPU and
+ * context switching between threads too. However, we need many threads for blocking HTTP and database calls.
+ * Nevertheless, this number can be further limited, because the number of actually working database threads
+ * is limited by the size of our database pool. The goal is to separate concerns into processing and blocking only
+ * threads.
+ */
+public class AsyncScheduler extends AbstractAsyncScheduler {
+
+    public AsyncScheduler(Logger logger, Executor processingPool) {
+        super(logger, Executors.newVirtualThreadPerTaskExecutor());
+
+        logger.info("Using optimized green threads with Java 21");
+    }
+
+    @Override
+    public CompletableFuture<Void> runAsync(Runnable task) {
+        return CompletableFuture
+                .runAsync(() -> process(task), processingPool)
+                .exceptionally(error -> {
+                    logger.warn("Error occurred on thread pool", error);
+                    return null;
+                });
+    }
+
+    @Override
+    public CompletableFuture<Void> runAsyncDelayed(Runnable task, Duration delay) {
+        return CompletableFuture.runAsync(() -> {
+            currentlyRunning.incrementAndGet();
+            try {
+                Thread.sleep(delay);
+                process(task);
+            } catch (InterruptedException interruptedException) {
+                // restore interrupt flag
+                Thread.currentThread().interrupt();
+            } finally {
+                currentlyRunning.getAndDecrement();
+            }
+        }, processingPool).exceptionally(error -> {
+            logger.warn("Error occurred on thread pool", error);
+            return null;
+        });
+    }
+}