On Mon, Nov 16, 2009 at 8:57 AM, Trevor Austin <[email protected]> wrote:
>
> I have an object type representing a threaded comment that I want to
> organize into trees - what's the best way to represent this
> relationship with Mapper? My naive idea is to do something like:
>
> class Comment extends LongKeyedMapper[Comment] with IdPK {
> ...
> object parentComment extends MappedLongForeignKey(this, Comment) {
> override def dbColumnName = "parent_comment_id"
> override def defaultValue = -1
> }
> ...
> def getParentComment():Box[Comment] = {
> if(this.parentComment.is == -1) {
> Empty
> }
> else {
> Comment.find(By(Comment.id, this.parentComment))
> }
> }
> }
>
> Is there a way to do this more directly so that Comment.parentComment
> just gives me something I can feed into type matching rather tahn
> doing the explicit check against -1 in a wrapper funciton?
>
parentComment.obj
That will return a Box[Comment] and cache the value (and also works with the
PreCache query param)
>
>
> >
>
--
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