Switch to JSpecify for nullability annotations

build.gradle.kts

@@ -9,7 +9,7 @@ plugins {
 
 group = "org.geysermc.event"
 
-version = "1.1-SNAPSHOT"
+version = "1.1.1-SNAPSHOT"
 
 repositories { mavenCentral() }
 
@@ -19,6 +19,7 @@ dependencies {
   implementation("org.slf4j", "slf4j-api", "2.0.7")
 
   compileOnly("org.checkerframework", "checker-qual", "3.19.0")
+  compileOnly("org.jspecify", "jspecify", "1.0.0")
 
   testImplementation("org.junit.jupiter", "junit-jupiter-api", "5.8.2")
   testRuntimeOnly("org.junit.jupiter", "junit-jupiter-engine", "5.8.2")

src/main/java/org/geysermc/event/FireResult.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -27,7 +27,6 @@
 import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.subscribe.Subscriber;
 
 public class FireResult {
@@ -51,7 +50,7 @@ public Map<Subscriber<?>, Throwable> exceptions() {
         return exceptions;
     }
 
-    public static FireResult resultFor(@NonNull Map<Subscriber<?>, Throwable> exceptions) {
+    public static FireResult resultFor(Map<Subscriber<?>, Throwable> exceptions) {
         Objects.requireNonNull(exceptions);
         if (exceptions.isEmpty()) {
             return ok();

src/main/java/org/geysermc/event/bus/BaseBus.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -25,7 +25,6 @@
 package org.geysermc.event.bus;
 
 import java.util.Set;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.FireResult;
 import org.geysermc.event.subscribe.Subscriber;
 
@@ -35,22 +34,22 @@ public interface BaseBus<E, S extends Subscriber<? extends E>> {
      *
      * @param subscription the event subscription
      */
-    void unsubscribe(@NonNull S subscription);
+    void unsubscribe(S subscription);
 
     /**
      * Fires the given event and log all exceptions that occur while executing this event.
      *
      * @param event the event to fire
      */
-    FireResult fire(@NonNull E event);
+    FireResult fire(E event);
 
     /**
      * Fires the given event silently.
      *
      * @param event the event to fire
      * @return the result of firing the given event
      */
-    FireResult fireSilently(@NonNull E event);
+    FireResult fireSilently(E event);
 
     /**
      * Gets the subscriptions for the given event class.
@@ -59,5 +58,5 @@ public interface BaseBus<E, S extends Subscriber<? extends E>> {
      * @param <T>        the value
      * @return the subscriptions for the event class
      */
-    @NonNull <T extends E> Set<? extends Subscriber<T>> subscribers(@NonNull Class<T> eventClass);
+    <T extends E> Set<? extends Subscriber<T>> subscribers(Class<T> eventClass);
 }

src/main/java/org/geysermc/event/bus/EventBus.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -25,7 +25,6 @@
 package org.geysermc.event.bus;
 
 import java.util.function.Consumer;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.PostOrder;
 import org.geysermc.event.subscribe.Subscriber;
 
@@ -35,12 +34,11 @@ public interface EventBus<E, S extends Subscriber<? extends E>> extends BaseBus<
      *
      * @param listener the listener
      */
-    void register(@NonNull Object listener);
+    void register(Object listener);
 
-    @NonNull <T extends E, U extends Subscriber<T>> U subscribe(@NonNull Class<T> eventClass, @NonNull Consumer<T> consumer);
+    <T extends E, U extends Subscriber<T>> U subscribe(Class<T> eventClass, Consumer<T> consumer);
 
-    @NonNull <T extends E, U extends Subscriber<T>> U subscribe(
-            @NonNull Class<T> eventClass, @NonNull Consumer<T> consumer, @NonNull PostOrder postOrder);
+    <T extends E, U extends Subscriber<T>> U subscribe(Class<T> eventClass, Consumer<T> consumer, PostOrder postOrder);
 
     void unregisterAll();
 }

src/main/java/org/geysermc/event/bus/OwnedEventBus.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -26,7 +26,6 @@
 
 import java.util.Set;
 import java.util.function.Consumer;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.PostOrder;
 import org.geysermc.event.subscribe.OwnedSubscriber;
 import org.geysermc.event.subscribe.Subscriber;
@@ -45,8 +44,7 @@ public interface OwnedEventBus<O, E, S extends OwnedSubscriber<O, ? extends E>>
      * @param <T>        the event class
      * @return the event subscription
      */
-    @NonNull <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
-            @NonNull O owner, @NonNull Class<T> eventClass, @NonNull Consumer<T> consumer);
+    <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(O owner, Class<T> eventClass, Consumer<T> consumer);
 
     /**
      * Subscribes to the given event see {@link Subscriber}.
@@ -62,27 +60,24 @@ public interface OwnedEventBus<O, E, S extends OwnedSubscriber<O, ? extends E>>
      * @param postOrder  the order of the subscriber
      * @return the event subscription
      */
-    @NonNull <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
-            @NonNull O owner,
-            @NonNull Class<T> eventClass,
-            @NonNull Consumer<T> consumer,
-            @NonNull PostOrder postOrder);
+    <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
+            O owner, Class<T> eventClass, Consumer<T> consumer, PostOrder postOrder);
 
     /**
      * Registers events for the given listener.
      *
      * @param owner    the extension registering the event
      * @param listener the listener
      */
-    void register(@NonNull O owner, @NonNull Object listener);
+    void register(O owner, Object listener);
 
     /**
      * Unregisters all events from a given owner.
      *
      * @param owner the extension
      */
-    void unregisterAll(@NonNull O owner);
+    void unregisterAll(O owner);
 
     @Override
-    @NonNull <T extends E> Set<? extends OwnedSubscriber<O, T>> subscribers(@NonNull Class<T> eventClass);
+    <T extends E> Set<? extends OwnedSubscriber<O, T>> subscribers(Class<T> eventClass);
 }

src/main/java/org/geysermc/event/bus/impl/BaseBusImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -42,7 +42,6 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.function.BiConsumer;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.FireResult;
 import org.geysermc.event.bus.BaseBus;
 import org.geysermc.event.bus.impl.util.Utils;
@@ -115,7 +114,7 @@ protected <T extends E> void register(Class<T> eventClass, S subscriber) {
 
     @SuppressWarnings("unchecked")
     protected <T extends E> void findSubscriptions(
-            @NonNull Object listener, TriConsumer<Class<T>, Subscribe, BiConsumer<Object, T>> consumer) {
+            Object listener, TriConsumer<Class<T>, Subscribe, BiConsumer<Object, T>> consumer) {
         Class<?> currentClass = listener.getClass();
         while (currentClass != Object.class) {
             for (Method method : currentClass.getDeclaredMethods()) {
@@ -152,7 +151,7 @@ protected <T extends E> void findSubscriptions(
     }
 
     @Override
-    public void unsubscribe(@NonNull S subscription) {
+    public void unsubscribe(S subscription) {
         synchronized (subscribers) {
             // we can trust the subscription because the implementation that will be used is final.
             Class<? extends E> eventClass = subscription.eventClass();
@@ -176,7 +175,7 @@ protected void unsubscribeAll() {
     }
 
     @Override
-    public FireResult fire(@NonNull E event) {
+    public FireResult fire(E event) {
         FireResult result = fireSilently(event);
         if (!result.success()) {
             result.exceptions().forEach((subscriber, throwable) -> {
@@ -192,7 +191,7 @@ public FireResult fire(@NonNull E event) {
 
     @Override
     @SuppressWarnings({"rawtypes", "unchecked"})
-    public FireResult fireSilently(@NonNull E event) {
+    public FireResult fireSilently(E event) {
         Map<Subscriber<?>, Throwable> thrown = new HashMap<>();
 
         for (Subscriber subscriber : sortedSubscribers(event.getClass())) {

src/main/java/org/geysermc/event/bus/impl/EventBusImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,7 +28,6 @@
 import java.util.Set;
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.PostOrder;
 import org.geysermc.event.bus.EventBus;
 import org.geysermc.event.subscribe.Subscribe;
@@ -38,17 +37,14 @@ public abstract class EventBusImpl<E, S extends Subscriber<? extends E>> extends
         implements EventBus<E, S> {
 
     protected abstract <H, T extends E, B extends Subscriber<T>> B makeSubscription(
-            @NonNull Class<T> eventClass,
-            @NonNull Subscribe subscribe,
-            @NonNull H listener,
-            @NonNull BiConsumer<H, T> handler);
+            Class<T> eventClass, Subscribe subscribe, H listener, BiConsumer<H, T> handler);
 
     protected abstract <T extends E, B extends Subscriber<T>> B makeSubscription(
-            @NonNull Class<T> eventClass, @NonNull Consumer<T> handler, @NonNull PostOrder postOrder);
+            Class<T> eventClass, Consumer<T> handler, PostOrder postOrder);
 
     @Override
     @SuppressWarnings("unchecked")
-    public void register(@NonNull Object listener) {
+    public void register(Object listener) {
         findSubscriptions(listener, (eventType, subscribe, handler) -> {
             S subscriber = (S) makeSubscription(eventType, subscribe, listener, handler);
 
@@ -57,15 +53,14 @@ public void register(@NonNull Object listener) {
     }
 
     @Override
-    @NonNull public <T extends E, U extends Subscriber<T>> U subscribe(
-            @NonNull Class<T> eventClass, @NonNull Consumer<T> consumer) {
+    public <T extends E, U extends Subscriber<T>> U subscribe(Class<T> eventClass, Consumer<T> consumer) {
         return subscribe(eventClass, consumer, PostOrder.NORMAL);
     }
 
     @Override
     @SuppressWarnings("unchecked")
-    public @NonNull <T extends E, U extends Subscriber<T>> U subscribe(
-            @NonNull Class<T> eventClass, @NonNull Consumer<T> consumer, @NonNull PostOrder postOrder) {
+    public <T extends E, U extends Subscriber<T>> U subscribe(
+            Class<T> eventClass, Consumer<T> consumer, PostOrder postOrder) {
         U subscription = makeSubscription(eventClass, consumer, postOrder);
         register(eventClass, (S) subscription);
         return subscription;
@@ -77,7 +72,7 @@ public void unregisterAll() {
     }
 
     @Override
-    @NonNull public <T extends E> Set<? extends Subscriber<T>> subscribers(@NonNull Class<T> eventClass) {
+    public <T extends E> Set<? extends Subscriber<T>> subscribers(Class<T> eventClass) {
         return Collections.unmodifiableSet(eventSubscribers(eventClass));
     }
 }

src/main/java/org/geysermc/event/bus/impl/OwnedEventBusImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 GeyserMC <https://geysermc.org>
+ * Copyright (c) 2022-2026 GeyserMC <https://geysermc.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -31,7 +31,6 @@
 import java.util.Set;
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
-import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.PostOrder;
 import org.geysermc.event.bus.OwnedEventBus;
 import org.geysermc.event.subscribe.OwnedSubscriber;
@@ -45,28 +44,20 @@ public abstract class OwnedEventBusImpl<O, E, S extends OwnedSubscriber<O, ? ext
             Multimaps.synchronizedSetMultimap(HashMultimap.create());
 
     protected abstract <L, T extends E, B extends OwnedSubscriber<O, T>> B makeSubscription(
-            @NonNull O owner,
-            @NonNull Class<T> eventClass,
-            @NonNull Subscribe subscribe,
-            @NonNull L listener,
-            @NonNull BiConsumer<L, T> handler);
+            O owner, Class<T> eventClass, Subscribe subscribe, L listener, BiConsumer<L, T> handler);
 
     protected abstract <T extends E, B extends OwnedSubscriber<O, T>> B makeSubscription(
-            @NonNull O owner, @NonNull Class<T> eventClass, @NonNull Consumer<T> handler, @NonNull PostOrder postOrder);
+            O owner, Class<T> eventClass, Consumer<T> handler, PostOrder postOrder);
 
     @Override
-    @NonNull public <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
-            @NonNull O owner, @NonNull Class<T> eventClass, @NonNull Consumer<T> handler) {
+    public <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
+            O owner, Class<T> eventClass, Consumer<T> handler) {
         return subscribe(owner, eventClass, handler, PostOrder.NORMAL);
     }
 
     @Override
-    @NonNull @SuppressWarnings("unchecked")
     public <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
-            @NonNull O owner,
-            @NonNull Class<T> eventClass,
-            @NonNull Consumer<T> handler,
-            @NonNull PostOrder postOrder) {
+            O owner, Class<T> eventClass, Consumer<T> handler, PostOrder postOrder) {
         OwnedSubscriber<O, T> subscription = makeSubscription(owner, eventClass, handler, postOrder);
 
         synchronized (ownedSubscribers) {
@@ -79,7 +70,7 @@ public <T extends E, U extends OwnedSubscriber<O, T>> U subscribe(
 
     @Override
     @SuppressWarnings("unchecked")
-    public void register(@NonNull O owner, @NonNull Object listener) {
+    public void register(O owner, Object listener) {
         findSubscriptions(listener, (eventClass, subscribe, handler) -> {
             S subscriber = (S) makeSubscription(owner, eventClass, subscribe, listener, handler);
 
@@ -89,12 +80,12 @@ public void register(@NonNull O owner, @NonNull Object listener) {
     }
 
     @Override
-    public void unregisterAll(@NonNull O owner) {
+    public void unregisterAll(O owner) {
         unsubscribeMany(castGenericSet(ownedSubscribers.removeAll(owner)));
     }
 
     @Override
-    @NonNull public <T extends E> Set<? extends OwnedSubscriber<O, T>> subscribers(@NonNull Class<T> eventClass) {
+    public <T extends E> Set<? extends OwnedSubscriber<O, T>> subscribers(Class<T> eventClass) {
         return Collections.unmodifiableSet(eventSubscribers(eventClass));
     }
 }