Fix EventListeners for Java

fix #738

mirai-core-api/src/commonMain/kotlin/event/JvmMethodListeners.kt

@@ -14,6 +14,7 @@
 package net.mamoe.mirai.event
 
 import kotlinx.coroutines.*
+import net.mamoe.mirai.utils.EventListenerLikeJava
 import java.lang.reflect.Method
 import kotlin.coroutines.CoroutineContext
 import kotlin.coroutines.EmptyCoroutineContext
@@ -238,6 +239,23 @@ public fun CoroutineScope.registerEvents(
     }
 }
 
+private fun Method.isKotlinFunction(): Boolean {
+
+    if (getDeclaredAnnotation(EventListenerLikeJava::class.java) != null) return false
+    if (declaringClass.getDeclaredAnnotation(EventListenerLikeJava::class.java) != null) return false
+
+    @Suppress("RemoveRedundantQualifierName") // for strict
+    return declaringClass.getDeclaredAnnotation(kotlin.Metadata::class.java) != null
+}
+
+private fun Method.invokeWithErrorReport(self: Any?, vararg args: Any?): Any? = try {
+    invoke(self, *args)
+} catch (exception: IllegalArgumentException) {
+    throw IllegalArgumentException(
+        "Internal Error: $exception, method=${this}, this=$self, arguments=$args, please report to https://github.com/mamoe/mirai",
+        exception
+    )
+}
 
 @Suppress("UNCHECKED_CAST")
 private fun Method.registerEvent(
@@ -248,7 +266,7 @@ private fun Method.registerEvent(
 ): Listener<Event> {
     this.isAccessible = true
     val kotlinFunction = kotlin.runCatching { this.kotlinFunction }.getOrNull()
-    return if (kotlinFunction != null) {
+    return if (kotlinFunction != null && isKotlinFunction()) {
         // kotlin functions
 
         val param = kotlinFunction.parameters
@@ -337,7 +355,7 @@ private fun Method.registerEvent(
 
         val paramType = this.parameters[0].type
         check(this.parameterCount == 1 && Event::class.java.isAssignableFrom(paramType)) {
-            "Illegal method parameter. Required one exact Event subclass. found $paramType"
+            "Illegal method parameter. Required one exact Event subclass. found ${this.parameters.contentToString()}"
         }
         when (this.returnType) {
             Void::class.java, Void.TYPE, Nothing::class.java -> {
@@ -350,11 +368,11 @@ private fun Method.registerEvent(
                     if (annotation.ignoreCancelled) {
                         if ((this as? CancellableEvent)?.isCancelled != true) {
                             withContext(Dispatchers.IO) {
-                                this@registerEvent.invoke(owner, this)
+                                this@registerEvent.invokeWithErrorReport(owner, this@subscribeAlways)
                             }
                         }
                     } else withContext(Dispatchers.IO) {
-                        this@registerEvent.invoke(owner, this)
+                        this@registerEvent.invokeWithErrorReport(owner, this@subscribeAlways)
                     }
                 }
             }
@@ -368,11 +386,11 @@ private fun Method.registerEvent(
                     if (annotation.ignoreCancelled) {
                         if ((this as? CancellableEvent)?.isCancelled != true) {
                             withContext(Dispatchers.IO) {
-                                this@registerEvent.invoke(owner, this) as ListeningStatus
+                                this@registerEvent.invokeWithErrorReport(owner, this@subscribe) as ListeningStatus
                             }
                         } else ListeningStatus.LISTENING
                     } else withContext(Dispatchers.IO) {
-                        this@registerEvent.invoke(owner, this) as ListeningStatus
+                        this@registerEvent.invokeWithErrorReport(owner, this@subscribe) as ListeningStatus
                     }
 
                 }

mirai-core-api/src/commonMain/kotlin/utils/Annotations.kt

@@ -60,4 +60,12 @@ internal annotation class PlannedRemoval(val version: String)
 @PlannedRemoval("2.0-M2")
 internal annotation class MemberDeprecatedApi(val message: String)
 
+/**
+ * 该注解仅用于测试 EventHandler
+ *
+ * 标注了此注解的意为像处理 java 方法那样处理 kotlin 方法
+ */
+@Retention(AnnotationRetention.RUNTIME)
+internal annotation class EventListenerLikeJava
+
 

mirai-core-api/src/jvmTest/java/net/mamoe/mirai/event/JvmMethodEventsTestJava.java

@@ -1,61 +0,0 @@
-/*
- * Copyright 2019-2020 Mamoe Technologies and contributors.
- *
- *  此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
- *  Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
- *
- *  https://github.com/mamoe/mirai/blob/master/LICENSE
- */
-
-package net.mamoe.mirai.event;
-
-import org.junit.jupiter.api.Test;
-
-import java.util.concurrent.atomic.AtomicInteger;
-
-import static kotlin.test.AssertionsKt.assertEquals;
-
-public class JvmMethodEventsTestJava extends SimpleListenerHost {
-    private final AtomicInteger called = new AtomicInteger(0);
-
-    @EventHandler
-    public void ev(TestEvent event) {
-        called.incrementAndGet();
-    }
-
-    @EventHandler
-    public Void ev2(TestEvent event) {
-        called.incrementAndGet();
-        return null;
-    }
-
-    @EventHandler
-    public ListeningStatus ev3(TestEvent event) {
-        called.incrementAndGet();
-        return ListeningStatus.LISTENING;
-    }
-
-    @EventHandler
-    public void ev(TestEvent event, TestEvent event2) {
-        called.incrementAndGet();
-    }
-
-    @EventHandler
-    public Void ev2(TestEvent event, TestEvent event2) {
-        called.incrementAndGet();
-        return null;
-    }
-
-    @EventHandler
-    public ListeningStatus ev3(TestEvent event, TestEvent event2) {
-        called.incrementAndGet();
-        return ListeningStatus.LISTENING;
-    }
-
-    @Test
-    public void test() {
-        Events.registerEvents(this);
-        EventKt.broadcast(new TestEvent());
-        assertEquals(6, called.get(), null);
-    }
-}

mirai-core-api/src/jvmTest/kotlin/event/JvmMethodEventsTestJava.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019-2020 Mamoe Technologies and contributors.
+ *
+ *  此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ *  Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ *  https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+package net.mamoe.mirai.event
+
+import net.mamoe.mirai.JavaFriendlyAPI
+import net.mamoe.mirai.utils.EventListenerLikeJava
+import org.junit.jupiter.api.Test
+import java.util.concurrent.atomic.AtomicInteger
+import kotlin.test.assertEquals
+
+@EventListenerLikeJava
+@JavaFriendlyAPI
+internal class JvmMethodEventsTestJava : SimpleListenerHost() {
+    private val called = AtomicInteger(0)
+
+    @EventHandler
+    fun ev(event: TestEvent?) {
+        called.incrementAndGet()
+    }
+
+    @EventHandler
+    fun ev2(event: TestEvent?): Void? {
+        called.incrementAndGet()
+        return null
+    }
+
+    @EventHandler
+    fun ev3(event: TestEvent?): ListeningStatus? {
+        called.incrementAndGet()
+        return ListeningStatus.LISTENING
+    }
+
+    @Test
+    fun test() {
+        this.registerEvents()
+        TestEvent().__broadcastJava()
+        assertEquals(3, called.get(), null)
+    }
+}