Oracle ADF DB Sequence Generating

import oracle.jbo.server.SequenceImpl;

SequenceImpl orderIdSeq = new SequenceImpl("ORDERS_SEQ", this.getDBTransaction());
orderIdSeq.getSequenceNumber();
String pOrderId = orderIdSeq.getSequenceNumber().toString();

More details:

http://docs.oracle.com/cd/E24382_01/apirefs.1112/e17483/oracle/jbo/server/SequenceImpl.html