problem with derby driver

[vitaly87]

Hello!
I have a problem to connect to db.
My erorrs are:

ption in thread "AWT-EventQueue-0" java.lang.ExceptionInInitializerError
	at org.apache.derby.jdbc.AutoloadedDriver.getDriverModule(Unknown Source)
	at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
	at java.sql.DriverManager.getConnection(DriverManager.java:582)
	at java.sql.DriverManager.getConnection(DriverManager.java:185)
	at setUpDb.FirstStart.isDbExist(FirstStart.java:29)

what dose it mean?
I am using derby drive with netbeans.

the errors in this line:

this.con = DriverManager.getConnection("jdbc:derby:"+getDBSystemDir(), "demo", "demo");

thanks for help