The main site of DCEVM didn't clearly explain how to install DCEVM on Linux. Running "java -jar installer.jar" in Linux (when accessed via PuTTy) gave me the following exception.
[admin@LINUXBOX jdk1.7.0_55]$ java -jar DCEVM-full-7u79-installer.jar
java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:207)
at java.awt.Window.<init>(Window.java:535)
at java.awt.Frame.<init>(Frame.java:420)
at javax.swing.JFrame.<init>(JFrame.java:224)
at com.github.dcevm.installer.MainWindow.<init>(MainWindow.java:43)
at com.github.dcevm.installer.Main.main(Main.java:46)
Exception in thread "main" java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:207)
at java.awt.Window.<init>(Window.java:535)
at java.awt.Frame.<init>(Frame.java:420)
at java.awt.Frame.<init>(Frame.java:385)
at javax.swing.SwingUtilities$SharedOwnerFrame.<init>(SwingUtilities.java:1757)
at javax.swing.SwingUtilities.getSharedOwnerFrame(SwingUtilities.java:1832)
at javax.swing.JOptionPane.getRootFrame(JOptionPane.java:1697)
at javax.swing.JOptionPane.showOptionDialog(JOptionPane.java:863)
at javax.swing.JOptionPane.showMessageDialog(JOptionPane.java:667)
at javax.swing.JOptionPane.showMessageDialog(JOptionPane.java:638)
at com.github.dcevm.installer.Main.main(Main.java:51)
If required, I am also ready to use a Virtual Box installed Desktop Linux to try it, which then I can copy (patched JDK) into my original Linux box thereafter.
So, how can I install DCEVM on Linux (for Java 7)? Do I need a Desktop-based Linux for that?
[admin@TESTBEDPEGSEARCH jdk1.7.0_55]$ echo $DISPLAY
[admin@TESTBEDPEGSEARCH jdk1.7.0_55]$ java -version
java version "1.7.0_55"
Java(TM) SE Runtime Environment (build 1.7.0_55-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.55-b03, mixed mode)
The DISPLAY
variable is only set when a X11 session is active. When you login on a remote machine with ssh, this usually is not the case.
There are two possible solutions:
DISPLAY
variable.