From 2e62c98c4564683e5ba7af367173413739e89dcb Mon Sep 17 00:00:00 2001
From: Luck <git@lucko.me>
Date: Wed, 24 Mar 2021 12:40:24 +0000
Subject: [PATCH] Avoid blocking worker pool for command timeout check (#2951)

3rd time lucky...
---
 .../common/command/CommandManager.java        |  6 ++-
 .../plugin/scheduler/SchedulerAdapter.java    | 42 -------------------
 2 files changed, 5 insertions(+), 43 deletions(-)

diff --git a/common/src/main/java/me/lucko/luckperms/common/command/CommandManager.java b/common/src/main/java/me/lucko/luckperms/common/command/CommandManager.java
index 00a99522c..fc61cafd0 100644
--- a/common/src/main/java/me/lucko/luckperms/common/command/CommandManager.java
+++ b/common/src/main/java/me/lucko/luckperms/common/command/CommandManager.java
@@ -182,7 +182,11 @@ public class CommandManager {
         }, this.executor);
 
         // schedule another task to catch if the command doesn't complete after 10 seconds
-        timeoutTask.set(scheduler.awaitTimeout(future, 10, TimeUnit.SECONDS, () -> handleCommandTimeout(executorThread, argsCopy)));
+        timeoutTask.set(scheduler.asyncLater(() -> {
+            if (!future.isDone()) {
+                handleCommandTimeout(executorThread, argsCopy);
+            }
+        }, 10, TimeUnit.SECONDS));
 
         return future;
     }
diff --git a/common/src/main/java/me/lucko/luckperms/common/plugin/scheduler/SchedulerAdapter.java b/common/src/main/java/me/lucko/luckperms/common/plugin/scheduler/SchedulerAdapter.java
index ab7849a01..1be23bfbc 100644
--- a/common/src/main/java/me/lucko/luckperms/common/plugin/scheduler/SchedulerAdapter.java
+++ b/common/src/main/java/me/lucko/luckperms/common/plugin/scheduler/SchedulerAdapter.java
@@ -25,12 +25,8 @@
 
 package me.lucko.luckperms.common.plugin.scheduler;
 
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
-import java.util.concurrent.atomic.AtomicReference;
 
 /**
  * A scheduler for running tasks using the systems provided by the platform
@@ -89,44 +85,6 @@ public interface SchedulerAdapter {
      */
     SchedulerTask asyncRepeating(Runnable task, long interval, TimeUnit unit);
 
-    /**
-     * Waits for the given time for {@code future} to complete. If the future isn't completed,
-     * {@code onTimeout} is executed.
-     *
-     * @param future the future to wait for
-     * @param timeout the time to wait
-     * @param unit the unit of timeout
-     * @param onTimeout the function to execute when the timeout expires
-     */
-    default SchedulerTask awaitTimeout(CompletableFuture<?> future, long timeout, TimeUnit unit, Runnable onTimeout) {
-        // a reference to the thread blocking on the future
-        AtomicReference<Thread> thread = new AtomicReference<>();
-
-        // in a new thread, await the completion of the future up to the given timeout
-        executeAsync(() -> {
-            thread.set(Thread.currentThread());
-            try {
-                future.get(timeout, unit);
-            } catch (InterruptedException | ExecutionException e) {
-                // ignore - this probably means the future completed successfully!
-            } catch (TimeoutException e) {
-                // run the timeout task
-                onTimeout.run();
-            } finally {
-                thread.set(null);
-            }
-        });
-
-        // to cancel the timeout task, just interrupt the thread that is blocking on the future
-        // and it will gracefully stop.
-        return () -> {
-            Thread t;
-            if ((t = thread.get()) != null) {
-                t.interrupt();
-            }
-        };
-    }
-
     /**
      * Shuts down the scheduler instance.
      *