Hibernate/JPA throws ConstraintViolationException when a SequenceGenerator is used and the sequence generator is also used by some external application

Issue

• The org.hibernate.id.enhanced.SequenceStyleGenerator retrieves the sequence value thanks to a nextval call and subtracts the JPA allocationSize in order to use range values from (nexval - allocationSize) to nexval. We would prefer the range to be from nexval to (nexval + allocationSize) instead.