David,
In src/share/native/java/lang/java_props.h the new field should really
also be in ifdef MACOSX.
The change to System.c allays my concerns there.
You can also consider the hotspot changes Reviewed.
Thanks,
David H.
On 24/10/2013 1:52 PM, David DeHaven wrote:
Another option (I think would make everyone happy) would be to add a native
method to LWCToolkit.{java,m} that implements isAquaSession and returns a
boolean. Call this new method in the static initializer and use it's return
value to set java.awt.headless before calling initIDs. This will still be done
early enough that Toolkit.java will end up wrapping LWCToolkit in a
HeadlessToolkit, since it first initializes the wrapped toolkit *then* checks
to see if it needs to be wrapped. Then all that code in java_props* and
System.c could be removed.
I like this idea. But it needs testing.
Cool, I'll poke at it when I get a chance.
Doesn't work in LWCToolkit, GraphicsEnvironment gets initialized first which
messes things up.
It sort of works in CGraphicsEnvironment. The problem there is
GraphicsEnvironment.isHeadless() is called at least once prior to
CGraphicsEnvironment being loaded which then caches the value (false) so just
changing the system property doesn't do anything. I added a protected method to
change headless and it works, but I'm not entirely happy with that approach and
I'm not convinced there won't be other side effects. For one thing, what is
calling isHeadless before CGE gets loaded and will it cope with the mode
changing? I don't think we have time to chase down all the issues that might
manifest from that change, when we know for certain the setting the property in
System.c works fine.
I think the safest bet at this point is to move all the java_props.awt_headless
field related code into #ifdef blocks so they only exist on Mac OS X. That will
address the cross-platform concern and fix this issue. I just thought it would
be useful for other platforms (especially embedded) to be able to poll their
environment and set themselves up accordingly...
Updated (hopefully final...) webrev:
http://cr.openjdk.java.net/~ddehaven/8025673/jdk.3/
Changes from last version:
http://cr.openjdk.java.net/~ddehaven/8025673/jdk.3/webrev.delta/index.html
(src/windows/native/java/lang/java_props_md.c only shows up because of the
delta webrev, it gets reverted back to the way it was)
As a side note, SplashScreen calls isHeadless and dumps a nice ugly stack trace
in a non-GUI session. It does this in the existing code so that's something
that'll need to be addressed as a separate issue. Also, the message returned by
GraphicsEnvironment.getHeadlessMessage() isn't correct for Mac, that should
either be made more generic or let the platform impl class return that string
(if it's even known or loaded at the time...).
-DrD-
