Test priorities for inheritance

README.md

@@ -225,7 +225,10 @@ To avoid this, system events never cause system events and instead just issue a
 
 When a superclass or an interface of an event listener defines event handlers, they will be detected and registered by Event Bus, even if they are `private`.
 If an event handler is overridden by the listener, the `@Event` annotation of the overridden method is automatically considered present on the overriding method.
-If the overridden method contains an implementation, it is ignored as expected.
+If the overridden method already contains an implementation in the superclass, the superclass implementation is ignored as expected.
+
+The `@Priority` and `@Polymorphic` annotations are inherited both on a class and on a method level.
+If the priority or polymorphism has to be redefined on an inherited handler, the `@Event` annotation has to be added explicitly.
 
 ## Debugging
 

core/src/main/java/dev/kske/eventbus/core/EventBus.java

@@ -7,7 +7,6 @@ import java.lang.reflect.*;
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Consumer;
-import java.util.stream.Collectors;
 
 import dev.kske.eventbus.core.handler.*;
 
@@ -272,8 +271,9 @@ public final class EventBus {
 		Set<Method> methods = getMethodsAnnotatedWith(listenerClass, Event.class);
 
 		// Recursively add superclass handlers
-		if (listenerClass.getSuperclass() != null)
-			methods.addAll(getHandlerMethods(listenerClass.getSuperclass()));
+		Class<?> superClass = listenerClass.getSuperclass();
+		if (superClass != null && superClass != Object.class)
+			methods.addAll(getHandlerMethods(superClass));
 
 		// Recursively add interface handlers
 		for (Class<?> iClass : listenerClass.getInterfaces())
@@ -292,9 +292,12 @@ public final class EventBus {
 	 */
 	private Set<Method> getMethodsAnnotatedWith(Class<?> enclosingClass,
 		Class<? extends Annotation> annotationClass) {
-		return Arrays.stream(enclosingClass.getDeclaredMethods())
-			.filter(m -> m.isAnnotationPresent(annotationClass))
-			.collect(Collectors.toSet());
+		var methods = new HashSet<Method>();
+		for (var method : enclosingClass.getDeclaredMethods())
+			if (method.isAnnotationPresent(annotationClass))
+				methods.add(method);
+
+		return methods;
 	}
 
 	/**

core/src/test/java/dev/kske/eventbus/core/InheritanceTest.java

@@ -5,7 +5,8 @@ import static org.junit.jupiter.api.Assertions.assertSame;
 import org.junit.jupiter.api.Test;
 
 /**
- * Tests whether event handlers correctly work in the context of an inheritance hierarchy.
+ * Tests whether event handlers correctly work in the context of an inheritance hierarchy. The
+ * effect of handler priorities is also accounted for.
  *
  * @author Kai S. K. Engelbart
  * @since 1.3.0
@@ -20,12 +21,12 @@ class InheritanceTest extends SimpleEventListenerBase implements SimpleEventList
 		var event = new SimpleEvent();
 
 		bus.dispatch(event);
-		assertSame(4, event.getCounter());
+		assertSame(3, event.getCounter());
 	}
 
 	@Override
 	void onSimpleEventAbstractHandler(SimpleEvent event) {
-		event.increment();
+		assertSame(1, event.getCounter());
 	}
 
 	@Override
@@ -35,6 +36,7 @@ class InheritanceTest extends SimpleEventListenerBase implements SimpleEventList
 
 	@Event
 	private void onSimpleEventPrivate(SimpleEvent event) {
+		assertSame(0, event.getCounter());
 		event.increment();
 	}
 }

core/src/test/java/dev/kske/eventbus/core/SimpleEventListenerBase.java

@@ -1,20 +1,25 @@
 package dev.kske.eventbus.core;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 /**
  * An abstract class defining a package-private and a private handler for {@link SimpleEvent}.
  *
  * @author Kai S. K. Engelbart
  * @since 1.3.0
  */
+@Priority(200)
 abstract class SimpleEventListenerBase {
 
 	@Event
 	void onSimpleEventAbstractHandler(SimpleEvent event) {
-		event.increment();
+		fail("This handler should not be invoked");
 	}
 
+	@Priority(150)
 	@Event
 	private void onSimpleEventPrivate(SimpleEvent event) {
+		assertSame(1, event.getCounter());
 		event.increment();
 	}
 }

core/src/test/java/dev/kske/eventbus/core/SimpleEventListenerInterface.java

@@ -8,6 +8,7 @@ package dev.kske.eventbus.core;
  */
 interface SimpleEventListenerInterface {
 
+	@Priority(120)
 	@Event
 	void onSimpleEventInterfaceHandler(SimpleEvent event);
 }