Running in non-GUI / non windowing servers

Q: I am getting the following error when running your library jPDFPrint in our SunOS environment. How can I fix it?

Exception in thread "main" java.lang.InternalError: Can't connect to X11 window server 
using 'localhost:0.0' as the value of the DISPLAY variable.
at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)
at sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:134)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:141)
at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:62)
at sun.awt.motif.MToolkit.<clinit>(MToolkit.java:81)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:141)
at java.awt.Toolkit$2.run(Toolkit.java:748)
at java.security.AccessController.doPrivileged(Native Method)
at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:739)

A: Our libraries use Java Swing classes when printing or working with images for instance. When initialized, these classes need a windowing GUI environment.

If you are running in a console-only server, you will need to run in headless mode. This tells Java to simulate a graphical environment so the Swing classes can initialize properly.

To run in headless mode, add this argument to your classpath or server startup:
-Djava.awt.headless=true