RFR(L) 8136930: Simplify use of module-system options by custom launchers

[harold seigel]

Hi Alan,

The JVM does not look for the -m (or --module) option.  Instead, it 
checks if property  "jdk.module.main" is non-null.  If it is non-null 
then the JVM uses the option name in its "Cannot use the following 
option when dumping the shared archive" message, as in:

     > $JAVA_TEST/bin/java -Xshare:dump -m my_mod
     Error occurred during initialization of VM
     Cannot use the following option when dumping the shared archive: -m

Unfortunately, it prints "-m" regardless of whether -m or --module was 
specified.

Harold


On 7/18/2016 3:13 AM, Alan Bateman wrote:
> On 18/07/2016 00:05, harold seigel wrote:
>
>> Hi,
>>
>> Please review these Hotspot VM only changes to process the seven 
>> module-specific options that have been renamed to have gnu-like 
>> names.  JDK changes for this bug will be reviewed separately.
>>
>> Descriptions of these options are here 
>> <http://openjdk.java.net/jeps/293>.  For these six options, 
>> --module-path, --upgrade-module-path, --add-modules, --limit-modules, 
>> --add-reads, and --add-exports, the JVM just sets a system property.  
>> For the --patch-module option, the JVM sets a system property and 
>> then processes the option in the same way as when it was named -Xpatch.
>>
>> Additionally, the JVM now checks properties specified on the command 
>> line.  If a property matches one of the properties used by one of the 
>> above options then the JVM ignores the property. This forces users to 
>> use the explicit option when wanting to do things like add a module 
>> or a package export.
>>
>> The RFR contains two new tests.  Also, many existing tests were 
>> changed to use the new option names.
>>
>> JBS Bug: https://bugs.openjdk.java.net/browse/JDK-8136930
>>
>> Webrev: http://cr.openjdk.java.net/~hseigel/bug_8136930.hs/
> A passing comment on unsupported_options (options not allowed when 
> using -Xshare:dump) then it has -m in the list. I assume that should 
> not be there. That is java launcher option, the VM don't see or 
> unrecognize it, also it's long form is --module.
>
> -Alan