| Re: [eclipselink-users] JPA 2 @OrderColumn question |
Set, and HashSet are not ordered. These collection types have no order in Java, so I'm not sure what expect??? If you want order, you need to use a List in Java. Lists are generally more usable collection types. You can add a constraint to your join table to enforce no duplicates. NBW wrote: > > > I was reading over the docs [1] regarding Eclipselink's support for > @OrderColumn. It looks like this only applies to List and not Set. The > reason I ask is because I have a ManyToMany bi-directional relationship > (using a join table) which is a Set and is implemented with a HashSet > because the collection can't have duplicates. > > I wanted to order the entries in this set using @OrderColumn, but it > appears I can only apply this to List, however using List will break my > unique requirement. Is this understanding correct? > > If so what is the recommended strategy for this case? > > Thanks, > > -Noah > > [1] - http://wiki.eclipse.org/EclipseLink/Examples/JPA/2.0/OrderColumns > > > ----- http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland http://www.eclipse.org/eclipselink/ EclipseLink , http://www.oracle.com/technology/products/ias/toplink/ TopLink Wiki: http://wiki.eclipse.org/EclipseLink EclipseLink , http://wiki.oracle.com/page/TopLink TopLink Forums: http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink , http://www.eclipse.org/forums/index.php?t=thread&frm_id=111&S=1b00bfd151289b297688823a00683aca EclipseLink Book: http://en.wikibooks.org/wiki/Java_Persistence Java Persistence Blog: http://java-persistence-performance.blogspot.com/ Java Persistence Performance -- View this message in context: http://old.nabble.com/JPA-2-%40OrderColumn-question-tp33972744p33976159.html Sent from the EclipseLink - Users mailing list archive at Nabble.com.