Add convenience method to ObjectPooler (#130)

src/main/java/com/gtnewhorizon/gtnhlib/util/ObjectPooler.java

@@ -1,16 +1,21 @@
 package com.gtnewhorizon.gtnhlib.util;
 
-import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.function.Supplier;
 
+import org.jetbrains.annotations.NotNull;
+
+import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+
 public class ObjectPooler<T> {
 
     private final Supplier<T> instanceSupplier;
-    private final ArrayList<T> availableInstances;
+    private final ObjectArrayList<T> availableInstances;
 
     public ObjectPooler(Supplier<T> instanceSupplier) {
         this.instanceSupplier = instanceSupplier;
-        this.availableInstances = new ArrayList<>();
+        this.availableInstances = new ObjectArrayList<>();
     }
 
     public T getInstance() {
@@ -21,6 +26,20 @@ public class ObjectPooler<T> {
     }
 
     public void releaseInstance(T instance) {
+        if (instance == null) return;
         this.availableInstances.add(instance);
     }
+
+    public void releaseInstances(Collection<T> instances) {
+        instances.forEach(this::releaseInstance);
+        instances.clear();
+    }
+
+    /**
+     * Uses arraycopy instead of a loop. Faster, but doesn't check that the input is nonnull. Use with care!
+     */
+    public void releaseInstances(@NotNull T[] instances) {
+        this.availableInstances.addElements(availableInstances.size(), instances);
+        Arrays.fill(instances, null);
+    }
 }