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Re: [eclipselink-users] Lazying-loading and Collection.size()

size() will instantiate lazy collections in EclipseLink and any other JPA
implementation that I know of.  I'm not sure the JPA spec says anything
about it.



cowwoc wrote:
> 
> Hi,
> 
> What does the JPA standard (and alternatively EclipseLink) say about Lazy
> Loading and Collection/Set/List.size()? If the collection hasn't been
> initialized yet, does size() simply invoke a count(*) query or does it
> retrieve the entire collection including its elements?
> 
> I'm thinking of the following use-case:
> 
> 1) int size = myList.size();
> 2) Object randomElement = myList.get((int) (Math.random() * size));
> 
> What is guaranteed to happen under the hood according to JPA and according
> to EclipseLink? Ideally I want to pass a Collection around my API, instead
> of forcing it to be Query-aware and issue SQL statements explicitly.
> 
> Thank you,
> Gili
> 


-----
---
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.nabble.com/EclipseLink-f26430.html EclipseLink 
Book:  http://en.wikibooks.org/wiki/Java_Persistence Java Persistence 
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