JAVA+JDBC+Open Office Base

import java.sql.*;
package databaza;

public class TestDb {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("hai");


try {
Class.forName("org.hsqldb.jdbcDriver");
}
catch(ClassNotFoundException e) {
System.out.println(e);
}

try {
Connection con=null;
try{
con=DriverManager.getConnection("jdbc:hsqldb:file:/home/tomas/Plocha/databaza.odb");
}catch(Exception e){
System.out.println(e.getMessage());
}
System.out.println(con.toString());

Statement st=con.createStatement();
System.out.println(st.toString());
ResultSet rs=st.executeQuery("select * from DATABAZA.databazaPotravin");
System.out.println(rs.getFloat("Tuky"));


st.close();
con.close();

}
catch(SQLException e){
System.out.println(e);
}


}

}

The database is already in use by another process: lockFile: org.hsqldb.persist.LockFile@79d4c31e[file =/home/tomas/Plocha/databaza.odb.lck, exists=true, locked=false, valid=false, ] method: checkHeartbeat read: 2010-07-12 14:40:35.697 heartbeat - read: -6540 ms.
Exception in thread "main" java.lang.NullPointerException
        at TestDb.main(TestDb.java:28)
Java Result: 1

java.sql.SQLException: Table not found in statement [SELECT * FROM databazaPotravin]