NoClassDefFoundError while accessing GraphicsEnvironment.getLocalGraphicsEnvironment on Tomcat.

Question

I have an application which is running on tomcat, one of the methods is, creating a simple thumbnail from an jpeg image. The functions works fine offline and a week ago also on tomcat. But now i get the following error:

java.lang.NoClassDefFoundError
java.lang.Class.forName0(Native Method)
java.lang.Class.forName(Class.java:164)
java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:68)
java.awt.image.BufferedImage.createGraphics(BufferedImage.java:1141)
eval.impl.ImageEval.getThumbnail(ImageEval.java:155)
eval.impl.ImageServlet.doGet(ImageServlet.java:79)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

I don't think that i have change anything what should influence this (actually i didn't change the function at all according to the svn repository), so it must be a library problem. But i can't figure out what is missing. Here are the actual lines from the getThumbnail function, where the error occures:

     BufferedImage thumbImage = new BufferedImage(thumbWidth, 
   thumbHeight, BufferedImage.TYPE_INT_RGB);
 Graphics2D graphics2D = thumbImage.createGraphics();
 graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
   RenderingHints.VALUE_INTERPOLATION_BILINEAR);
 graphics2D.drawImage(simage, 0, 0, thumbWidth, thumbHeight, null);

[edit] I decided to update the problem description a little. Yes it seems that he can not find some class from java.awt or one related to that. But they do exist on the server in the jvm. Java headless mode doesn't solve the problem. In another project the exact same code, but inside an axis2 webservice on this server is working fine. [/edit]

Answer 1

Is this server running java in server mode - I hear that doesn't load in the AWT classes.

Answer 2

It was running a week ago, and now it is not.

THEREFORE, YOU CHANGED SOMETHING BETWEEN "working" and "not working".

Go back to the working config (if you can), and rigorously track what you changed. If you don't have a backup of the working config, then meticulously go back through what you've done between working and non-working until you find what you changed.

It may not be code - it could be a config file, etc.

Best of luck,

-R

Answer 3

Likely, something changed in your Classpath. Either the actual classpath changed or it is looking for a file that has been moved. Have you recently done a "clean and deploy"?

Answer 4

If you are deploying this on *nix, and you don't have an X window system running anymore, that could explain it. Even if you do, if you aren't exporting the DISPLAY system variable to the process that starts the JVM, or if you are but it is not actually valid, it could cause such an issue.

That would at least explain why you didn't change any configuration in tomcat, but still have a problem.

Answer 5

If your NoClassDefFoundError has no message at all, then this means two things:

1. The JVM has already tried and failed to load a class. Usually, this means the JVM was unable to complete static initialization for that class, i.e. assign values to any static fields and run any static { } blocks. Often, this is because the classes necessary to do this static initialization are missing.
2. You're using Java 5, not Java 6. (In Java 6, you get a 'Could not initialize class xyz' message instead.)

The problem class appears to be the one whose name is the value of the system property java.awt.graphicsenv. I would start by finding out the value of this property. What happens when you try to instantiate this class?