--- a/src/jdk.jpackage/share/classes/jdk/jpackage/internal/ApplicationLayout.java	Tue Oct 15 14:00:04 2019 -0400
+++ b/src/jdk.jpackage/share/classes/jdk/jpackage/internal/ApplicationLayout.java	Wed Oct 16 09:57:23 2019 -0400
@@ -144,7 +144,7 @@
             return macAppImage();
         }
 
-        throw new IllegalArgumentException("Unknown platform");
+        throw Platform.throwUnknownPlatformError();
     }
 
     static ApplicationLayout javaRuntime() {