Reading a serialized object, Tomcat

[Dominik Glodzik]

Hello everyone,

I seem to have a problem with my JSP application running on Apache Tomcat/6.0.14.

I catch the following exception:
org.apache.jasper.JasperException: javax.servlet.ServletException: java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkit

This happens when I tried to read in a file containing a serialized object.

File f = new File(path);
fis = new FileInputStream(f.getAbsolutePath());
in = new ObjectInputStream(fis);
experiment= (ExperimentalSetup)in.readObject();
in.close();

The class of the object, which is being red, contains an instance of a Swing class ImageIcon. This works fine on GlassFish on my machine, but gives an error when uploaded to Tomcat.

I'd welcome any suggestions how to read in the serialized object.

Dominik

[Stefan Evans]

The server you are running on is a *nix type?
Most probably without a monitor?
Check out headless mode to see if it might help: http://java.sun.com/developer/technicalArticles/J2SE/Desktop/headless/

I'm not sure if it will or not. The sun.* classes are not really intended for general use
Can you come up with a better approach than serializing java objects?

[Dominik Glodzik]

Hey,

thank you VERY much, it works.

Yes, the server runs Linux with no display.

To switch Tomcat to a headless mode, add the following line to catalina.sh
export CATALINA_OPTS=-Djava.awt.headless=true

Dominik