return noop pregen cache when the service is disabled and write pregen cache to temp file first then replace real one

core/src/main/java/com/volmit/iris/core/pregenerator/cache/PregenCacheImpl.java

@@ -7,6 +7,7 @@ import com.volmit.iris.Iris;
 import com.volmit.iris.util.data.Varint;
 import com.volmit.iris.util.documentation.ChunkCoordinates;
 import com.volmit.iris.util.documentation.RegionCoordinates;
+import com.volmit.iris.util.io.IO;
 import com.volmit.iris.util.parallel.HyperLock;
 import lombok.RequiredArgsConstructor;
 import net.jpountz.lz4.LZ4BlockInputStream;
@@ -82,8 +83,8 @@ class PregenCacheImpl implements PregenCache {
         hyperLock.lock(plate.pos.x, plate.pos.z);
         try {
             File file = fileForPlate(plate.pos);
-            try (var out = new DataOutputStream(new LZ4BlockOutputStream(new FileOutputStream(file)))) {
+            try {
-                plate.write(out);
+                IO.write(file, out -> new DataOutputStream(new LZ4BlockOutputStream(out)), plate::write);
             } catch (IOException e) {
                 Iris.error("Failed to write pregen cache " + file);
                 e.printStackTrace();

core/src/main/java/com/volmit/iris/core/service/GlobalCacheSVC.java

@@ -23,9 +23,11 @@ public class GlobalCacheSVC implements IrisService {
     private static final Cache<String, PregenCache> REFERENCE_CACHE = Caffeine.newBuilder().weakValues().build();
     private final KMap<String, PregenCache> globalCache = new KMap<>();
     private transient boolean lastState;
+    private static boolean disabled = true;
 
     @Override
     public void onEnable() {
+        disabled = false;
         lastState = !IrisSettings.get().getWorld().isGlobalPregenCache();
         if (lastState) return;
         Bukkit.getWorlds().forEach(this::createCache);
@@ -33,7 +35,8 @@ public class GlobalCacheSVC implements IrisService {
 
     @Override
     public void onDisable() {
-        globalCache.values().forEach(PregenCache::write);
+        disabled = true;
+        globalCache.qclear((world, cache) -> cache.write());
     }
 
     @Nullable
@@ -99,6 +102,7 @@ public class GlobalCacheSVC implements IrisService {
     }
 
     private static PregenCache createDefault0(String worldName) {
+        if (disabled) return PregenCache.EMPTY;
         return PregenCache.create(new File(Bukkit.getWorldContainer(), String.join(File.separator, worldName, "iris", "pregen"))).sync();
     }
 }

core/src/main/java/com/volmit/iris/util/collection/KMap.java

@@ -23,11 +23,9 @@ import com.volmit.iris.util.function.Consumer2;
 import com.volmit.iris.util.function.Consumer3;
 import com.volmit.iris.util.scheduling.Queue;
 
-import java.util.Collections;
+import java.util.*;
-import java.util.Comparator;
-import java.util.Enumeration;
-import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.BiConsumer;
 import java.util.function.BiFunction;
 
 @SuppressWarnings("ALL")
@@ -373,6 +371,20 @@ public class KMap<K, V> extends ConcurrentHashMap<K, V> {
         return g;
     }
 
+    public KMap<K, V> qclear(BiConsumer<K, V> action) {
+        final Iterator<Map.Entry<K, V>> it = entrySet().iterator();
+        while (it.hasNext()) {
+            final Map.Entry<K, V> entry = it.next();
+            it.remove();
+            try {
+                action.accept(entry.getKey(), entry.getValue());
+            } catch (Throwable e) {
+                Iris.reportError(e);
+            }
+        }
+        return this;
+    }
+
     /**
      * Create a keypair queue
      *

core/src/main/java/com/volmit/iris/util/io/IO.java

@@ -24,9 +24,13 @@ import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
 import com.volmit.iris.Iris;
 import com.volmit.iris.util.format.Form;
+import org.apache.commons.io.function.IOConsumer;
+import org.apache.commons.io.function.IOFunction;
 
 import java.io.*;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.StandardCopyOption;
 import java.security.DigestInputStream;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
@@ -1638,4 +1642,19 @@ public class IO {
         int ch2 = input2.read();
         return (ch2 == -1);
     }
+
+    public static <T extends OutputStream> void write(File file, IOFunction<FileOutputStream, T> builder, IOConsumer<T> action) throws IOException {
+        File dir = new File(file.getParentFile(), ".tmp");
+        dir.mkdirs();
+        dir.deleteOnExit();
+        File temp = File.createTempFile("iris",".bin", dir);
+        try {
+            try (var out = builder.apply(new FileOutputStream(temp))) {
+                action.accept(out);
+            }
+            Files.move(temp.toPath(), file.toPath(), StandardCopyOption.REPLACE_EXISTING);
+        } finally {
+            temp.delete();
+        }
+    }
 }