From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Mon, 5 Dec 2022 11:21:05 +0100
Subject: [PATCH] Unterminable executor utility

License: AGPL-3.0 (https://www.gnu.org/licenses/agpl-3.0.html)
Gale - https://galemc.org

diff --git a/src/main/java/org/galemc/gale/concurrent/UnterminableExecutorService.java b/src/main/java/org/galemc/gale/concurrent/UnterminableExecutorService.java
new file mode 100644
index 0000000000000000000000000000000000000000..ce53ca5aa53cc1c11b36afba17615a91c18834d3
--- /dev/null
+++ b/src/main/java/org/galemc/gale/concurrent/UnterminableExecutorService.java
@@ -0,0 +1,50 @@
+// Gale - unterminable executor utility
+
+package org.galemc.gale.concurrent;
+
+import org.galemc.gale.executor.annotation.thread.AnyThreadSafe;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.concurrent.AbstractExecutorService;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * An {@link ExecutorService} that directly extends {@link AbstractExecutorService}, and cannot be shut down.
+ * This type of executor is useful for an executor that merely exists to implement the {@link ExecutorService}
+ * interface and forward tasks to another executor or executor's queue, and therefore creates no threads that need
+ * to stop either.
+ *
+ * @author Martijn Muijsers under AGPL-3.0
+ */
+@AnyThreadSafe
+public abstract class UnterminableExecutorService extends AbstractExecutorService {
+
+    @Override
+    public void shutdown() {
+        throw new UnsupportedOperationException();
+    }
+
+    @NotNull
+    @Override
+    public List<Runnable> shutdownNow() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean isShutdown() {
+        return false;
+    }
+
+    @Override
+    public boolean isTerminated() {
+        return false;
+    }
+
+    @Override
+    public boolean awaitTermination(long l, @NotNull TimeUnit timeUnit) throws InterruptedException {
+        throw new UnsupportedOperationException();
+    }
+
+}