이벤트 order 이벤트 핸들링

src/main/java/com/example/template/OrderException.java

@@ -0,0 +1,11 @@
+package com.example.template;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(code = HttpStatus.INTERNAL_SERVER_ERROR) //(reason = "No Available stock!")
+public class OrderException extends RuntimeException {
+    public OrderException(String message) {
+        super(message);
+    }
+}