Re: very, very serious problem - null values where objects should be

From: Tomi NA (hefes..mail.com)
Date: Sat Jun 10 2006 - 03:24:30 EDT

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    On 6/8/06, Andrus Adamchik <andru..bjectstyle.org> wrote:
    > Can you run it in Eclipse (or some other) debugger and step through
    > 'getToLevel3Object' method? Then you can actually check the state of
    > the objects and see if there is anything weird.
    >
    > If you still can't find anything, please open a Jira issue with a
    > DataMap XML file attached with at least these three entities:
    > Level1Object, Level2Object and Level3Object, with relationships
    > between the entities preserved the way you have them now. I'll see if
    > I can reproduce this.

    I fell back to the scientific method: I made a list of suspects and
    tested them one by one, changing only one thing at a time.
    Here's the culprit (from cayenne.xml):

            <property name="cayenne.DataRowStore.snapshot.size" value="10"/>

    Now, when I change the value to, say, 10000, I don't see the missing
    values problem.
    The good news is obviously (or apparently?) that I don't have a
    showstopper bug anymore. There's still a worm of doubt in my mind that
    I simply masked the problem, made it appear later (when a lot more
    objects are loaded into memory) rather than sooner. Is this so?
    The bad news is that if I make the DataRowStoresnapshot.size large,
    I'm back to square one: I'll have a number of rich clients in a LAN,
    each running inside his own jvm, with his own cache - in this case,
    the cache gets in the way of data consistency.

    So:
    1.) why did I get null objects with value="10"?
    2.) did I solve the problem (don't think so, the more I think about
    it) or simply hidd it?
    2.) how do I solve the
    multiple-rich-clients-in-individual-jvms-with-their-own-cache problem?

    t.n.a.



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