async mob spawning

divinemc-server/src/main/java/org/bxteam/divinemc/DivineConfig.java

@@ -299,6 +299,7 @@ public class DivineConfig {
     public static boolean forceMinecraftCommand = false;
     public static boolean disableLeafDecay = false;
     public static boolean commandBlockParseResultsCaching = true;
+    public static boolean enableAsyncSpawning = true;
     private static void miscSettings() {
         skipUselessSecondaryPoiSensor = getBoolean("settings.misc.skip-useless-secondary-poi-sensor", skipUselessSecondaryPoiSensor);
         clumpOrbs = getBoolean("settings.misc.clump-orbs", clumpOrbs,
@@ -318,6 +319,8 @@ public class DivineConfig {
             "Disables leaf block decay.");
         commandBlockParseResultsCaching = getBoolean("settings.misc.command-block-parse-results-caching", commandBlockParseResultsCaching,
             "Caches the parse results of command blocks, can significantly reduce performance impact.");
+        enableAsyncSpawning = getBoolean("settings.misc.enable-async-spawning", enableAsyncSpawning,
+            "Enables optimization that will offload much of the computational effort involved with spawning new mobs to a different thread.");
     }
 
     public static boolean disableDisconnectSpam = false;

divinemc-server/src/main/java/org/bxteam/divinemc/util/AsyncProcessor.java

@@ -0,0 +1,59 @@
+package org.bxteam.divinemc.util;
+
+import ca.spottedleaf.moonrise.common.util.TickThread;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
+
+public class AsyncProcessor {
+    private static final Logger LOGGER = LogManager.getLogger(AsyncProcessor.class);
+
+    private final BlockingQueue<Runnable> taskQueue;
+    private final Thread workerThread;
+    private volatile boolean isRunning;
+
+    public AsyncProcessor(String threadName) {
+        this.taskQueue = new LinkedBlockingQueue<>();
+        this.isRunning = true;
+
+        this.workerThread = new TickThread(() -> {
+            while (isRunning || !taskQueue.isEmpty()) {
+                try {
+                    Runnable task = taskQueue.take();
+                    task.run();
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    break;
+                } catch (Exception e) {
+                    LOGGER.error("An unexpected error occurred when running async processor: {}", e.getMessage(), e);
+                }
+            }
+        }, threadName);
+
+        this.workerThread.start();
+    }
+
+    public void submit(Runnable task) {
+        if (!isRunning) {
+            throw new IllegalStateException("AsyncExecutor is not running.");
+        }
+
+        taskQueue.offer(task);
+    }
+
+    public void shutdown() {
+        isRunning = false;
+        workerThread.interrupt();
+    }
+
+    public void shutdownNow() {
+        isRunning = false;
+        workerThread.interrupt();
+        taskQueue.clear();
+    }
+
+    public boolean isRunning() {
+        return isRunning;
+    }
+}