Refactoring.

src/main/java/ca/recrown/islandsurvivalcraft/caching/Cache.java

@@ -8,13 +8,13 @@ import java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock;
 public class Cache<K, V> {
     private final int maxSize;
     private final ConcurrentHashMap<K, CacheValue<K, V>> data;
-    private final UsageStack<K, V> usage = new UsageStack<>();
+    private final CacheUsageStack<K, V> usage = new CacheUsageStack<>();
     private final ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
     private final WriteLock writeLock = lock.writeLock();
     private final ReadLock readLock = lock.readLock();
 
     public Cache(int maxSize) {
-        data = new ConcurrentHashMap<>(maxSize + 1, 0.75f, 6);
+        data = new ConcurrentHashMap<>(maxSize + 1, 0.75f, 16);
         this.maxSize = maxSize;
     }
 

src/main/java/ca/recrown/islandsurvivalcraft/caching/CacheUsageStack.java

@@ -2,7 +2,8 @@ package ca.recrown.islandsurvivalcraft.caching;
 
 import java.util.concurrent.locks.ReentrantLock;
 
-class UsageStack<K, V> {
+class CacheUsageStack<K, V> {
+    private volatile int size;
     private volatile CacheValue<K, V> first, last;
     private final ReentrantLock lock = new ReentrantLock();
 
@@ -15,6 +16,7 @@ class UsageStack<K, V> {
         }
         value.front = null;
         first = value;
+        size++;
     }
 
     private void removeValue(CacheValue<K, V> value) {
@@ -30,6 +32,7 @@ class UsageStack<K, V> {
         }
         value.front = null;
         value.back = null;
+        size--;
     }
 
     public void moveToTop(CacheValue<K, V> value) {
@@ -86,4 +89,8 @@ class UsageStack<K, V> {
             lock.unlock();
         }
     }
+
+    public int size() {
+        return size;
+    }
 }