--- a/src/jdk.jpackage/share/classes/jdk/jpackage/internal/Platform.java	Tue Oct 15 14:00:04 2019 -0400
+++ b/src/jdk.jpackage/share/classes/jdk/jpackage/internal/Platform.java	Wed Oct 16 09:57:23 2019 -0400
@@ -114,4 +114,8 @@
     static boolean isLinux() {
         return getPlatform() == LINUX;
     }
+
+    static RuntimeException throwUnknownPlatformError() {
+        throw new IllegalArgumentException("Unknown platform");
+    }
 }