I just found out about this change to restrict redefining some modules: http://hg.openjdk.java.net/jigsaw/jake/hotspot/rev/52cdbd4a5999 and I can only repeat my warning that this further restriction will make it harder to migrate to Java 9 and might break tools in the process. It does neither seem to me that a good alternative is offered if opening core modules is required to make a Java agent work.
Is this change intending to freeze classes of java.base or to restrict exporting? If so, does this also affect the command line to change the properties of certain modules? Was an evaluation done how this change might impact existing tools? Thanks for explaining this change. Best regards, Rafael
