java - "SecurityException: sealing violation" when starting Derby connection

Question

I need do start the derby server from my java application using "org.apache.derby.drda.NetworkServerControl" class.
When I try to start the server it throws an exception.

Code:

NetworkServerControl server = null; 
server=new NetworkServerControl(InetAddress.getLocalHost(),1527,"user","123")
server.start(new PrintWriter(System.out));

Error:

Caused by: java.lang.SecurityException: sealing violation: package org.apache.derby.impl.store.raw.xact is sealed

Can anybody tell me the reason for this error?

Answer 1

You have probably Derby classes twice on your classpath. Look for Derby classes in some another jar archive and use them only once.