We're going on an Adventure! (#4842)

Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>
Co-authored-by: zml <zml@stellardrift.ca>
Co-authored-by: Mariell Hoversholm <proximyst@proximyst.com>

Spigot-API-Patches/0038-Misc-Utils.patch

@@ -0,0 +1,46 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: vemacs <d@nkmem.es>
+Date: Wed, 23 Nov 2016 12:53:43 -0500
+Subject: [PATCH] Misc Utils
+
+
+diff --git a/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java b/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java
+new file mode 100644
+index 0000000000000000000000000000000000000000..5bb677ce585b856b3d3e589e29786a29619c56a7
+--- /dev/null
++++ b/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java
+@@ -0,0 +1,34 @@
++package com.destroystokyo.paper.utils;
++
++import java.util.concurrent.ConcurrentLinkedQueue;
++import java.util.concurrent.atomic.LongAdder;
++import org.jetbrains.annotations.NotNull;
++import org.jetbrains.annotations.Nullable;
++
++public class CachedSizeConcurrentLinkedQueue<E> extends ConcurrentLinkedQueue<E> {
++    private final LongAdder cachedSize = new LongAdder();
++
++    @Override
++    public boolean add(@NotNull E e) {
++        boolean result = super.add(e);
++        if (result) {
++            cachedSize.increment();
++        }
++        return result;
++    }
++
++    @Nullable
++    @Override
++    public E poll() {
++        E result = super.poll();
++        if (result != null) {
++            cachedSize.decrement();
++        }
++        return result;
++    }
++
++    @Override
++    public int size() {
++        return cachedSize.intValue();
++    }
++}