"No X11 DISPLAY variable" - what does it mean?

[gemm]

Hello,

I am trying to install a program on my linux machine (I am using Slackware). I receive the following mistake, and I do not understand it. Could you advise me how to approach the problem? Thank you.

Here is what I get:

~$ java -jar gate-5.0-beta1-build3048-installer.jar
- ERROR -
java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
at java.awt.GraphicsEnvironment.checkHeadless(Graphic sEnvironment.java:159)
at java.awt.Window.<init>(Window.java:407)
at java.awt.Frame.<init>(Frame.java:402)
at net.sourceforge.mlf.metouia.borders.MetouiaDotsBuf fer.<init>(MetouiaDotsBuffer.java:105)
at net.sourceforge.mlf.metouia.borders.MetouiaDots.<i nit>(MetouiaDots.java:66)
at net.sourceforge.mlf.metouia.borders.MetouiaToolBar Border.<init>(MetouiaToolBarBorder.java:49)
at net.sourceforge.mlf.metouia.MetouiaLookAndFeel.ini tComponentDefaults(MetouiaLookAndFeel.java:241)
at javax.swing.plaf.basic.BasicLookAndFeel.getDefault s(BasicLookAndFeel.java:130)
at javax.swing.plaf.metal.MetalLookAndFeel.getDefault s(MetalLookAndFeel.java:1591)
at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:537)
at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:581)
at com.izforge.izpack.installer.GUIInstaller.loadLook AndFeel(GUIInstaller.java:373)
at com.izforge.izpack.installer.GUIInstaller.<init>(G UIInstaller.java:116)
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Construc tor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:30
at com.izforge.izpack.installer.Installer.main(Instal ler.java:62)

[Ziplock]

Hi there,

$DISPLAY is an environment variable that defines where X (the GUI system used by Linux) sends the windows, desktop etc. The default one is :0.0 I think try running the following before running your program:

export DISPLAY=:0.0

[gemm]

Hi!
thank you very much, it worked with
export DISPLAY=:0.0

[Ziplock]

No worries - glad I could help you.