- What error do you get when you *don't* use -Djava.awt.headless=true ?
- What is your DISPLAY environment variable set to?
If your DISPLAY variable isn't set, you might need to either use -X when ssh'ing into the box, or modify your sshd_config and set X11Forwarding yes. Some SSH servers don't allow X11 forwarding by default.
On 12/22/05, iksrazal <[EMAIL PROTECTED]> wrote:
Just to address your curiosity - X11 is a protocol. Its completely capable of
running a keyboard and a display remotely - much I suppose like Windows
terminal server (never used it). xclock most certainly needs X11 - runlevel 3
in front of the keyboard (locally) in any type of unix for example won't be
able to run xclock. (Will give 'Error, can't open display' ) . Or with
KDE/Gnome and the like you can type ctrl-alt-F1 and you'll get a shell with
X11, which also can't run xclock. X11/ssh allows programs that need a GUI to
be invoked remotely.
A good example of running a java awt/swing program remotely is JMeter - as you
don't want the program affecting performace testing. That works over X11/ssh
just fine.
With that out of the way, any help highly appreciated.
iksrazal
Em Quinta 22 Dezembro 2005 13:10, o Ron Reynolds escreveu:
> from the JavaDocs
> http://java.sun.com/j2se/1.4.2/docs/api/java/awt/HeadlessException.html it
> sounds like a headless system should have no display or UI components
> whatsoever ("Thrown when code that is dependent on a keyboard, display, or
> mouse is called in an environment that does not support a keyboard,
> display, or mouse"). i'm curious how tcpmon could possibly work without
> display.... also i thought if something like 'xclock' works then you
> wouldn't have to run in headless mode... ??
>
> ................ron.
>
> > Hi all,
> >
> > I'm trying to run tcpmon remotely. I'm using X11 forwarding over ssh. X11
> > is working fine - I can type 'xclock' on the remote machine and it works.
> >
> > However, I get this error:
> >
> > /home/iksrazal/axis-1_3/lib> java -cp axis.jar -Djava.awt.headless=true
> > org.apache.axis.utils.tcpmon 8090 localhost 9081
> > java.awt.HeadlessException
> > at
> > java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:121)
> > at java.awt.Window.<init>(Window.java:274)
> > at java.awt.Frame.<init>(Frame.java:401)
> > at javax.swing.JFrame.<init>(JFrame.java:198)
> > at org.apache.axis.utils.tcpmon .<init>(tcpmon.java:1814)
> > at org.apache.axis.utils.tcpmon.<init>(tcpmon.java:1861)
> > at org.apache.axis.utils.tcpmon.main(tcpmon.java:1900)
> >
> > As you can see I've tried java.awt.headless=true . Any ideas?
> >
> > iksrazal
