--- old/src/jdk.jlink/share/classes/jdk/tools/jlink/internal/plugins/SystemModuleDescriptorPlugin.java	2016-04-25 14:51:00.000000000 -0700
+++ new/src/jdk.jlink/share/classes/jdk/tools/jlink/internal/plugins/SystemModuleDescriptorPlugin.java	2016-04-25 14:51:00.000000000 -0700
@@ -485,11 +485,11 @@
                 }
 
                 if (md.version().isPresent()) {
-                    version(md.version().get());
+                    version(md.version().getWhenPresent());
                 }
 
                 if (md.mainClass().isPresent()) {
-                    mainClass(md.mainClass().get());
+                    mainClass(md.mainClass().getWhenPresent());
                 }
 
                 putModuleDescriptor();