Create new DB using JAVA

Hello,
 Can somebody send me a short demo example for creating new db instance 
in JAVA ?

 When I have already created DB I know connect to it, change some db 
parameters, but still I don't know how can I create new instance.

  This is example for setting up parameters what I'm using now:
     String dbUser = "dbm";      String dbPasswd = "dbm";

   DBM dbSession = DBM.dbDBM ("localhost", "my_db");
   // logon to dbm server
   dbSession.cmd ("user_logon " + dbUser + "," +  dbPassword);
   // send server command for starting the database
   result = dbSession.cmd ("db_warm");
   // set up some parameters
   result = session.cmd ("param_startsession");
   result = session.cmd ("param_put MAXUSERTASKS 5");
   result = session.cmd ("param_checkall");
   result = session.cmd ("param_commitsession");

 This is running OK. But  my problem is create new DB instance. I have try

   DBM dbSession = DBM.dbDBM ("localhost", "my_new_db");
   DBM.dbrootDBM("localhost", "c:\program files\sapdb\depend");
   result = session.cmd ("db_create");

   but I have an error -   com.sap.dbtech.rte.comm.RTEException: Server 
or DB unknown

   How can I do that?

 Thanks in advance for your answer,
  Julian