As Alan replied, custom launchers create a VM using the JNI invocation API specifying the VM options properly and no need to set -J. -J is a way JDK launchers to pass options to the runtime environment.
Mandy > On Jun 4, 2016, at 4:10 AM, Remi Forax <fo...@univ-mlv.fr> wrote: > > Hi Mandy, > did you think about using -J for specifying either VM options or module > options (the user really don't care) for custom launchers like we use -J to > specify VM option to javac ? > > cheers, > Rémi > > ----- Mail original ----- >> De: "Mandy Chung" <mandy.ch...@oracle.com> >> À: "jigsaw-dev" <jigsaw-dev@openjdk.java.net>, "hotspot-runtime-dev" >> <hotspot-runtime-...@openjdk.java.net> >> Envoyé: Samedi 4 Juin 2016 08:47:37 >> Objet: Review Request JDK-8136930 Examine implications for custom launchers, >> equivalent of java -X options in >> particular >> >> Webrev: >> http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8136930/webrev.00/ >> >> -modulepath, -addmods, -limitmods, -XaddExports, -XaddReads, -Xpatch are java >> launcher options in the current implementation. Custom launchers will have >> to use -D to set some system properties to configure module system. >> Different ways to configure module system is confusing and not friendly for >> environments using both java launcher and custom launchers. >> >> This patch pushes the handling of the module options into the VM. That will >> avoid the confusion between launcher and VM options and avoids needing to >> use system properties. All launcher implementations can configure the >> module system via JNI Invocation API setting these options in a unified way. >> The options and syntax remain the same as specified in JEP 261. >> >> For the non-repeating options, like the other VM options, the last one wins. >> The current implementation communicates the options to the module system >> through system properties, as a private interface, and these system >> properties will be removed once they are read during the module system >> initialization. These system properties are reserved as private interface >> and they will be ignored if they are set via -D in the command line. Harold >> implements the hotspot change and can explain further details. >> >> This patch will impact existing tests and scripts that set the system >> properties for example to break encapsulation in the command line e.g. >> -Djdk.launcher.addexports.<N>. They will need to be updated to replace the >> use of -D with the appropriate module option e.g. -XaddExports. Since they >> are new options in JDK 9, use -XX:+IgnoreUnrecognizedVMOptions if they need >> to be ignored by earlier releases. >> >> Mandy >> >> >>
