Parallel loading libraries

sources/src/main/java/io/akarin/server/mixin/core/Bootstrap.java

@@ -45,6 +45,6 @@ public class Bootstrap {
             args = "ldc=Loading libraries, please wait..."
     ))
     private static void notifyLoading(PrintStream stream, String text) {
-        LogWrapper.logger.info("Loading libraries, please wait..");
+        LogWrapper.logger.info("Loading libraries as parallel capable..");
     }
 }

sources/src/main/java/io/akarin/server/mixin/core/MixinMetrics.java

@@ -16,8 +16,6 @@ import org.spongepowered.asm.mixin.Shadow;
 import com.destroystokyo.paper.Metrics;
 import com.destroystokyo.paper.Metrics.CustomChart;
 
-import io.akarin.api.LogWrapper;
-
 @Mixin(value = Metrics.class, remap = false)
 public class MixinMetrics {
     // The url to which the data is sent - bukkit/Torch (keep our old name)

sources/src/main/java/io/akarin/server/mixin/core/ParallelRegistry.java

@@ -0,0 +1,141 @@
+package io.akarin.server.mixin.core;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.Redirect;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+
+import io.akarin.api.LogWrapper;
+import net.minecraft.server.BiomeBase;
+import net.minecraft.server.Block;
+import net.minecraft.server.BlockFire;
+import net.minecraft.server.DispenserRegistry;
+import net.minecraft.server.Enchantment;
+import net.minecraft.server.EntityTypes;
+import net.minecraft.server.Item;
+import net.minecraft.server.MobEffectList;
+import net.minecraft.server.PotionBrewer;
+import net.minecraft.server.PotionRegistry;
+import net.minecraft.server.SoundEffect;
+
+@Mixin(value = DispenserRegistry.class, remap = false)
+public class ParallelRegistry {
+    private static final ThreadFactory STAGE_FACTORY = new ThreadFactoryBuilder().setNameFormat("Parallel Registry Thread - %1$d").build();
+    
+    /**
+     * Registry order: SoundEffect -> Block -> BlockFire -> Item -> PotionBrewer -> BiomeBase
+     */
+    private static final ExecutorService STAGE_A = Executors.newSingleThreadExecutor(STAGE_FACTORY); // TODO go deeper!
+    /**
+     * Registry order: MobEffectList -> PotionRegistry
+     */
+    private static final ExecutorService STAGE_B = Executors.newSingleThreadExecutor(STAGE_FACTORY);
+    /**
+     * Registry order: Enchantment -> EntityTypes
+     */
+    private static final ExecutorService STAGE_C = Executors.newSingleThreadExecutor(STAGE_FACTORY);
+    
+    private static final int TERMINATION_IN_SEC = 30;
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/SoundEffect.b()V"
+    ))
+    private static void soundEffect() {
+        STAGE_A.execute(() -> SoundEffect.b());
+    }
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/Block.w()V"
+    ))
+    private static void block() {
+        STAGE_A.execute(() -> Block.w());
+    }
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/BlockFire.e()V"
+    ))
+    private static void blockFire() {
+        STAGE_A.execute(() -> BlockFire.e());
+    }
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/MobEffectList.k()V"
+    ))
+    private static void mobEffectList() {
+        STAGE_B.execute(() -> MobEffectList.k());
+    }
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/Enchantment.g()V"
+    ))
+    private static void enchantment() {
+        STAGE_C.execute(() -> Enchantment.g());
+    }
+    
+    @Redirect(method = "c()V", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/Item.t()V"
+    ))
+    private static void item() {
+        STAGE_A.execute(() -> Item.t());
+    }
+    
+    @Redirect(method = "c", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/PotionRegistry.b()V"
+    ))
+    private static void potionRegistry() {
+        STAGE_B.execute(() -> PotionRegistry.b());
+    }
+    
+    @Redirect(method = "c", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/PotionBrewer.a()V"
+    ))
+    private static void potionBrewer() {
+        STAGE_A.execute(() -> PotionBrewer.a());
+    }
+    
+    @Redirect(method = "c", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/EntityTypes.c()V"
+    ))
+    private static void entityTypes() {
+        STAGE_C.execute(() -> EntityTypes.c());
+    }
+    
+    @Redirect(method = "c", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/BiomeBase.q()V"
+    ))
+    private static void biomeBase() {
+        STAGE_A.execute(() -> BiomeBase.q());
+    }
+    
+    @Inject(method = "c", at = @At(
+            value = "INVOKE",
+            target = "net/minecraft/server/DispenserRegistry.b()V",
+            shift = At.Shift.BEFORE
+    ))
+    private static void await(CallbackInfo info) throws InterruptedException {
+        STAGE_A.shutdown();
+        STAGE_B.shutdown();
+        STAGE_C.shutdown();
+        STAGE_A.awaitTermination(TERMINATION_IN_SEC, TimeUnit.SECONDS);
+        STAGE_B.awaitTermination(TERMINATION_IN_SEC, TimeUnit.SECONDS);
+        STAGE_C.awaitTermination(TERMINATION_IN_SEC, TimeUnit.SECONDS);
+    }
+}