Error : Run a simple spark plugin

Spark Spark Dev
1

Hi everyone,

I am a beginner in the development Spark and I try to build a plugin, but I can not run a simple plugin.

run:
     [copy] Copying 1 file to D:\MyDocs\EclipseWorkSpace\sparkplugs\spark\plugins
     [java] java.lang.NoClassDefFoundError: de/javasoft/plaf/synthetica/SyntheticaBlueMoonLookAndFeel
     [java] Caused by: java.lang.ClassNotFoundException: de.javasoft.plaf.synthetica.SyntheticaBlueMoonLookAndFeel
     [java]  at java.net.URLClassLoader$1.run(Unknown Source)
     [java]  at java.security.AccessController.doPrivileged(Native Method)
     [java]  at java.net.URLClassLoader.findClass(Unknown Source)
     [java]  at java.lang.ClassLoader.loadClass(Unknown Source)
     [java]  at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
     [java]  at java.lang.ClassLoader.loadClass(Unknown Source)
     [java] Could not find the main class: org.jivesoftware.Spark.  Program will exit.
     [java] Exception in thread "main"      [java] Java Result: 1
BUILD SUCCESSFUL
Total time: 1 second

What is de/javasoft/plaf/synthetica/SyntheticaBlueMoonLookAndFeel class ?

Can you help me, please ?

Thanks !