<AWT Dev> [9] Review Request: 8076264 [macosx] Launching app on MacOSX requires enclosing class

[Kumar Srinivasan]

> I don't get it.  Either providing this information (what "java 
> program" is running - main class and/or command line) is generally 
> useful or it is not.  There's nothing macosx-specific about it.  
> Either provide a clean blessed api (i.e. not an environment variable) 
> and have

Are you equating environment variable to system property ?

Kumar

> AWT etc use it on every platform or do not provide it at all.  Hmmm... 
> come to think of it, "jps" gives a list of java processes and tries to 
> identify them using their main class, so there's cross-platform precedent.
>
> So please just figure out how to stop setting this environment 
> variable at all.
>
> On Fri, Apr 10, 2015 at 8:02 AM, Kumar Srinivasan 
> <kumar.x.srinivasan at oracle.com <mailto:kumar.x.srinivasan at oracle.com>> 
> wrote:
>
>     and it looks like sun.java.command is no longer exported to Java.
>
>     /*
>      * inject the -Dsun.java.command pseudo property into the args
>     structure
>      * this pseudo property is used in the HotSpot VM to expose the
>      * Java class name and arguments to the main method to the VM. The
>      * HotSpot VM uses this pseudo property to store the Java class name
>      * (or jar file name) and the arguments to the class's main method
>      * to the instrumentation memory region. The sun.java.command pseudo
>      * property is not exported by HotSpot to the Java layer.
>      */
>
>     I guess you could get it from the intrumentation or serviceability
>     layer, that may likely be an additional overhead.
>
>     Kumar
>
>     On 4/10/2015 6:47 AM, Sergey Bylokhov wrote:
>
>         On 10.04.15 15:28, Martin Buchholz wrote:
>
>
>             My biggest gripe about the Mac behavior was that java
>             startup was doing AWT-specific initialization even though
>             there is no AWT code here.  Figure out how to move this
>             code into the AWT module somehow?  Isn't this sort of
>             thing one of the goals of jigsaw?
>
>             But looking at SetMainClassForAWT I see that this is hard
>             to change.  It's a mess.  Why does AWT, SWT and JavaFX
>             want to get the name of the main class, but ... only on Mac?!
>
>         It is used to initialize the name of the application during
>         start of UI library. Since there is no public way to take the
>         mainclass from the launcher(see [1] and [2]) we need to pass
>         this value ourself. I suppose such functionality is missing(or
>         not implemented) on other platforms.
>
>         [1] https://bugs.openjdk.java.net/browse/JDK-4827318
>         [2]
>         http://stackoverflow.com/questions/939932/how-to-determine-main-class-at-runtime-in-threaded-java-application
>
>
>               969      * WARNING: This environment variable is an
>             implementation detail and
>               970      * isn't meant for use outside of the core
>             platform. The mechanism for
>               971      * passing this information from Java launcher
>             to other modules may
>               972      * change drastically between update release,
>             and it may even be
>               973      * removed or replaced with another mechanism.
>               974      *
>               975      * NOTE: It is used by SWT, and JavaFX.
>
>
>             On Wed, Apr 8, 2015 at 6:29 AM, Sergey Bylokhov
>             <Sergey.Bylokhov at oracle.com
>             <mailto:Sergey.Bylokhov at oracle.com>
>             <mailto:Sergey.Bylokhov at oracle.com
>             <mailto:Sergey.Bylokhov at oracle.com>>> wrote:
>
>                 Hello.
>                 Please review the fix for jdk 9.
>                 After the fix we clear all errors caused by
>             getCanonicalName() on
>                 the mainclass and leave JAVA_MAIN_CLASS_ empty. This
>             empty case
>                 will be handled in the NSApplicationAWT.m.
>                 Plus small cleanup suggested in the bug
>             report(jstring->jclass).
>
>                 Bug: https://bugs.openjdk.java.net/browse/JDK-8076264
>                 Webrev can be found at:
>             http://cr.openjdk.java.net/~serb/8076264/webrev.01
>             <http://cr.openjdk.java.net/%7Eserb/8076264/webrev.01>
>                 <http://cr.openjdk.java.net/%7Eserb/8076264/webrev.01>
>
>                 --     Best regards, Sergey.
>
>
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