Add VIRTUAL_NETTY support: ManualIoEventLoopTask, VirtualMultithreadManualIoEventLoopGroup

Author: franz1981

core/src/main/java/io/netty/loom/ManualIoEventLoopTask.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2026 The Netty VirtualThread Scheduler Project
+ *
+ * The Netty VirtualThread Scheduler Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at:
+ *
+ *   https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ */
+package io.netty.loom;
+
+import io.netty.channel.IoEventLoopGroup;
+import io.netty.channel.IoHandlerFactory;
+import io.netty.channel.ManualIoEventLoop;
+
+import java.util.concurrent.TimeUnit;
+
+public class ManualIoEventLoopTask extends ManualIoEventLoop implements Runnable {
+
+	private static final long RUNNING_YIELD_US = TimeUnit.MICROSECONDS
+			.toNanos(Integer.getInteger("io.netty.loom.running.yield.us", 1));
+
+	public ManualIoEventLoopTask(IoEventLoopGroup parent, Thread owningThread, IoHandlerFactory factory) {
+		super(parent, owningThread, factory);
+	}
+
+	@Override
+	public void run() {
+		while (!isShuttingDown()) {
+			run(0, RUNNING_YIELD_US);
+			Thread.yield();
+			runNonBlockingTasks(RUNNING_YIELD_US);
+			Thread.yield();
+		}
+		while (!isTerminated()) {
+			runNow();
+			Thread.yield();
+		}
+	}
+}

core/src/main/java/io/netty/loom/VirtualMultithreadManualIoEventLoopGroup.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2026 The Netty VirtualThread Scheduler Project
+ *
+ * The Netty VirtualThread Scheduler Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at:
+ *
+ *   https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ */
+package io.netty.loom;
+
+import io.netty.channel.IoEventLoop;
+import io.netty.channel.IoHandlerFactory;
+import io.netty.channel.MultiThreadIoEventLoopGroup;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.ThreadFactory;
+
+public class VirtualMultithreadManualIoEventLoopGroup extends MultiThreadIoEventLoopGroup {
+
+	private ThreadFactory threadFactory;
+
+	public VirtualMultithreadManualIoEventLoopGroup(int nThreads, IoHandlerFactory factory) {
+		super(nThreads, (Executor) null, factory);
+	}
+
+	@Override
+	protected IoEventLoop newChild(Executor executor, IoHandlerFactory ioHandlerFactory, Object... args) {
+		if (threadFactory == null) {
+			threadFactory = Thread.ofVirtual().factory();
+		}
+		var manualTask = new ManualIoEventLoopTask(this, null, ioHandlerFactory);
+		var newThread = threadFactory.newThread(manualTask);
+		manualTask.setOwningThread(newThread);
+		newThread.start();
+		return manualTask;
+	}
+}