Review Request JDK-8136930 Examine implications for custom launchers, equivalent of java -X options in particular

[Remi Forax]

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.chung at oracle.com>
> À: "jigsaw-dev" <jigsaw-dev at openjdk.java.net>, "hotspot-runtime-dev" <hotspot-runtime-dev at 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
> 
> 
>