diff --git a/application/src/main/kotlin/tw/waterballsa/gaas/application/usecases/EndGameUseCase.kt b/application/src/main/kotlin/tw/waterballsa/gaas/application/usecases/EndGameUseCase.kt
index 20a6d796..0a514125 100644
--- a/application/src/main/kotlin/tw/waterballsa/gaas/application/usecases/EndGameUseCase.kt
+++ b/application/src/main/kotlin/tw/waterballsa/gaas/application/usecases/EndGameUseCase.kt
@@ -5,7 +5,6 @@ import tw.waterballsa.gaas.application.repositories.RoomRepository
 import tw.waterballsa.gaas.application.repositories.UserRepository
 import tw.waterballsa.gaas.domain.Room
 import tw.waterballsa.gaas.events.EndedGameEvent
-import tw.waterballsa.gaas.events.EndedGameEvent.Data
 import tw.waterballsa.gaas.events.enums.EventMessageType.GAME_ENDED
 import javax.inject.Named
 
@@ -31,6 +30,6 @@ class EndGameUseCase(
 
 fun Room.endGameByGameService(): EndedGameEvent {
     val type = GAME_ENDED
-    val data = Data(roomId!!.value)
+    val data = EndedGameEvent.Data(roomId!!.value)
     return EndedGameEvent(type, data)
 }
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/EndedGameEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/EndedGameEvent.kt
index adff9db7..11b645cc 100644
--- a/domain/src/main/kotlin/tw/waterballsa/gaas/events/EndedGameEvent.kt
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/EndedGameEvent.kt
@@ -2,11 +2,14 @@ package tw.waterballsa.gaas.events
 
 import tw.waterballsa.gaas.events.enums.EventMessageType
 
-data class EndedGameEvent(
-    val type: EventMessageType,
-    val data: Data,
-) : DomainEvent() {
+class EndedGameEvent(
+    type: EventMessageType,
+    val data: Data
+) : SocketIoResponseEvent(type) {
     data class Data(
         val roomId: String,
     )
+
+
+    override fun getEventData(): Any = data
 }
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerJoinedRoomEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerJoinedRoomEvent.kt
index f69ce08d..4bf6c971 100644
--- a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerJoinedRoomEvent.kt
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerJoinedRoomEvent.kt
@@ -2,10 +2,10 @@ package tw.waterballsa.gaas.events
 
 import tw.waterballsa.gaas.events.enums.EventMessageType
 
-data class PlayerJoinedRoomEvent(
-    val type: EventMessageType,
-    val data: Data,
-) : DomainEvent() {
+class PlayerJoinedRoomEvent(
+    type: EventMessageType,
+    val data: Data
+) : SocketIoResponseEvent(type) {
     data class Data(
         val user: Player,
         val roomId: String,
@@ -15,4 +15,8 @@ data class PlayerJoinedRoomEvent(
             val nickname: String,
         )
     }
+
+
+    override fun getEventData(): Any = data
+
 }
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerLeavedRoomEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerLeavedRoomEvent.kt
index a09a22a5..6a2adbbf 100644
--- a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerLeavedRoomEvent.kt
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerLeavedRoomEvent.kt
@@ -2,10 +2,10 @@ package tw.waterballsa.gaas.events
 
 import tw.waterballsa.gaas.events.enums.EventMessageType
 
-data class PlayerLeavedRoomEvent(
-    val type: EventMessageType,
-    val data: Data,
-) : DomainEvent() {
+class PlayerLeavedRoomEvent(
+    type: EventMessageType,
+    val data: Data
+) : SocketIoResponseEvent(type) {
     data class Data(
         val user: Player,
         val roomId: String,
@@ -15,4 +15,8 @@ data class PlayerLeavedRoomEvent(
             val nickname: String,
         )
     }
+
+
+    override fun getEventData(): Any = data
+
 }
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerReadinessChangedEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerReadinessChangedEvent.kt
index 19b9c270..d1ba4cad 100644
--- a/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerReadinessChangedEvent.kt
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/PlayerReadinessChangedEvent.kt
@@ -2,10 +2,10 @@ package tw.waterballsa.gaas.events
 
 import tw.waterballsa.gaas.events.enums.EventMessageType
 
-data class PlayerReadinessChangedEvent(
-    val type: EventMessageType,
-    val data: Data,
-) : DomainEvent() {
+class PlayerReadinessChangedEvent(
+    type: EventMessageType,
+    val data: Data
+) : SocketIoResponseEvent(type) {
     data class Data(
         val user: User,
         val roomId: String,
@@ -15,4 +15,6 @@ data class PlayerReadinessChangedEvent(
             val nickname: String,
         )
     }
+
+    override fun getEventData(): Any = data
 }
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseData.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseData.kt
new file mode 100644
index 00000000..7da185d1
--- /dev/null
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseData.kt
@@ -0,0 +1,5 @@
+package tw.waterballsa.gaas.events
+
+interface SocketIoResponseData {
+    fun getEventData(): Any
+}
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseEvent.kt
new file mode 100644
index 00000000..99dbf6d1
--- /dev/null
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/SocketIoResponseEvent.kt
@@ -0,0 +1,5 @@
+package tw.waterballsa.gaas.events
+
+import tw.waterballsa.gaas.events.enums.EventMessageType
+
+abstract class SocketIoResponseEvent(val type: EventMessageType) : DomainEvent(), SocketIoResponseData
diff --git a/domain/src/main/kotlin/tw/waterballsa/gaas/events/StartedGameEvent.kt b/domain/src/main/kotlin/tw/waterballsa/gaas/events/StartedGameEvent.kt
index a0f7ca5c..ebd45c75 100644
--- a/domain/src/main/kotlin/tw/waterballsa/gaas/events/StartedGameEvent.kt
+++ b/domain/src/main/kotlin/tw/waterballsa/gaas/events/StartedGameEvent.kt
@@ -3,13 +3,15 @@ package tw.waterballsa.gaas.events
 import tw.waterballsa.gaas.domain.Room
 import tw.waterballsa.gaas.events.enums.EventMessageType
 
-data class StartedGameEvent(
-    val type: EventMessageType,
-    val data: Data,
-) : DomainEvent() {
-
+class StartedGameEvent(
+    type: EventMessageType,
+    val data: Data
+) : SocketIoResponseEvent(type) {
     data class Data(
         val gameUrl: String,
         val roomId: Room.Id,
     )
+
+
+    override fun getEventData(): Any = data
 }
diff --git a/spring/src/main/kotlin/tw/waterballsa/gaas/spring/eventbus/WebSocketEventBus.kt b/spring/src/main/kotlin/tw/waterballsa/gaas/spring/eventbus/WebSocketEventBus.kt
index fd3415e9..8d7cd509 100644
--- a/spring/src/main/kotlin/tw/waterballsa/gaas/spring/eventbus/WebSocketEventBus.kt
+++ b/spring/src/main/kotlin/tw/waterballsa/gaas/spring/eventbus/WebSocketEventBus.kt
@@ -7,8 +7,7 @@ import org.springframework.stereotype.Component
 import tw.waterballsa.gaas.application.eventbus.EventBus
 import tw.waterballsa.gaas.events.*
 import tw.waterballsa.gaas.spring.controllers.viewmodel.SocketioViewModel
-
-
+import kotlin.reflect.safeCast
 
 @Component
 class WebSocketEventBus(
@@ -17,38 +16,10 @@ class WebSocketEventBus(
 
     private val logger: Logger = LoggerFactory.getLogger(WebSocketEventBus::class.java)
 
-
     lateinit var viewModel: SocketioViewModel
-
-    // TODO broadcast the events!
     override fun broadcast(events: Collection<DomainEvent>) {
-
-        for (event in events) {
-            if (event is PlayerJoinedRoomEvent) {
-                val data = event.data
-                val type = event.type
-                socketIOServer.broadcastOperations.sendEvent(type.toString(), data)
-            } else if(event is PlayerLeavedRoomEvent){
-                val data = event.data
-                val type = event.type
-                socketIOServer.broadcastOperations.sendEvent(type.toString(), data)
-            } else if(event is PlayerReadinessChangedEvent){
-                val data = event.data
-                val type = event.type
-                socketIOServer.broadcastOperations.sendEvent(type.toString(), data)
-            } else if(event is StartedGameEvent){
-                val data = event.data
-                val type = event.type
-                socketIOServer.broadcastOperations.sendEvent(type.toString(), data)
-            } else if(event is UserUpdatedEvent){
-//                val data = event.data
-//                val type = event.type
-//                socketIOServer.broadcastOperations.sendEvent(type.toString(), data)
-            }
-
-        }
-
-
+        events.asSequence()
+            .mapNotNull { SocketIoResponseEvent::class.safeCast(it) }
+            .forEach { socketIOServer.broadcastOperations.sendEvent(it.type.toString(), it.getEventData()) }
     }
-
-}
\ No newline at end of file
+}