Remove the listener the JDA command handler added on bean destroyal

Author: Vampire

src/main/java/net/kautler/command/handler/CommandHandlerJda.java

@@ -34,6 +34,7 @@
 import org.apache.logging.log4j.Logger;
 
 import javax.annotation.PostConstruct;
+import javax.annotation.PreDestroy;
 import javax.enterprise.context.ApplicationScoped;
 import javax.enterprise.event.Event;
 import javax.enterprise.inject.Instance;
@@ -137,7 +138,7 @@ private void setCustomPrefixProvider(Instance<PrefixProvider<? super Message>> c
     }
 
     /**
-     * Adds this command handler to the injected {@code DiscordApi} instances as message create listener.
+     * Adds this command handler to the injected {@code JDA} and {@code ShardManager} instances as event listener.
      */
     @PostConstruct
     private void addListener() {
@@ -173,6 +174,21 @@ private void addListener() {
         }
     }
 
+    /**
+     * Removes this command handler from the injected {@code JDA} and {@code ShardManager} instances as event listener.
+     */
+    @PreDestroy
+    private void removeListener() {
+        Stream.concat(
+                jdas.stream(),
+                jdaCollections.stream().flatMap(Collection::stream)
+        ).forEach(jda -> jda.removeEventListener(this));
+        Stream.concat(
+                shardManagers.stream(),
+                shardManagerCollections.stream().flatMap(Collection::stream)
+        ).forEach(shardManager -> shardManager.removeEventListener(this));
+    }
+
     @Override
     public void onEvent(GenericEvent event) {
         if (event instanceof MessageReceivedEvent) {

src/test/groovy/net/kautler/command/handler/CommandHandlerJdaTest.groovy

@@ -373,6 +373,24 @@ class CommandHandlerJdaTest extends Specification {
             }
     }
 
+    @Use(ContextualInstanceCategory)
+    def 'shutting down the container should remove the listeners'() {
+        when:
+            weld.shutdown()
+
+        then:
+            [
+                    jda,
+                    jdaInCollection1,
+                    jdaInCollection2,
+                    shardManager,
+                    shardManagerInCollection1,
+                    shardManagerInCollection2
+            ].each {
+                1 * it.removeEventListener(commandHandlerJda.ci())
+            }
+    }
+
     @ApplicationScoped
     static class TestEventReceiver {
         @Inject