Thanks Robert! - Jason
On Mon, Jun 4, 2018, at 11:45 AM, Robert Munteanu wrote: > There are two questions I want to raise: > > 1. API related > > We have two methods: > > - stream() > - stream(Predicate<Resource>) > > which traverse the whole tree. the base stream() would traverse the whole tree, the branch selector parameter (Predicate<Resource>) is used to limit the traversal. The most common use case I give for this if you have a site with 10,000 pages on it. The number of nodes or resources in that structure could come close to 1 million nodes. If, however, you can find if a page matches your needs from the page node itself . You don't have to descend into the jcr:content sub tree. So instead of traversing a million nodes, you just traverse 10,000 As Dan mentioned, you could also just have that branch selector itself limit the depth of the search. > There were questions of whether this is OK or if we maybe need to > stream the children only. Could the API additions allow that? > > We can start with something like > > - stream(Predicate<Resource>, Set<TraversalOption>... ) > - stream(Predicate<Resource>) > - stream(Set<TraversalOption>...) If the traversal option defines only the children of the existing resource, then there is no need to define a branch selector. It's exclusionary. Which, makes the combinations kind of weird, It would make more sense to just name the method for getting the children as a stream something unique. > 2. Implementation related > > I think that the 'hasNext' method is not lazy, eagerly loading the > direct children of a resource when there are no more resources to load. > > If the resource has a large number of children we can end up taking > lots of memory, so I think we need to be more lazy with it, since the > streams framework can take advantage of that (IIRC). Is it possible to > ajust the implementation this way? Maybe. You would still need to have the hasNext() method correctly identify whether there is a next or not, so you would need to have a loop iterate through and checking. I would have to somehow find my way back to the correct location the next time the method is called. My biggest concern there is with the unordered children. Do I need to maintain state of the underling iteration that I'm checking? I'd ask that we go ahead and get it in as is, and I could pursue being more lazy on that call. I don't know how long that would take me and I'm still waiting for the gods of the internet to provide me a job where I can work on Sling as my job full time. > Thanks, > > Robert
