Apache JDO Project - Re: Support java.lang.Object as FCO

This is Interesting: Free IT Magazines  
Home > Archive > Apache JDO Project > August 2005 > Re: Support java.lang.Object as FCO





You are viewing an archived Text-only version of the thread. To view this thread in it's original format and/or if you want to reply to this thread please [click here]

Author Re: Support java.lang.Object as FCO
Andy Jefferson

2005-08-17, 5:45 pm

> Well we interpret all types as serialized=3D"false", but in section 18.14=
of
> the spec "java.lang" types (which Object is) are to be embedded=3D"true" =

by
> default. So we interpret this as serialising the Object into the table of
> the class, into a BLOB column.


Michelle,
before you change anything .... (was writing this while I received your rep=
ly)


That, of course, comes down to how you interpret the statement in the secti=
on=20
embedding 18.14.
<spec>
The embedded attribute specifies whether the field should be stored as part=
of=20
the containing instance instead of as its own instance in the datastore. It=
=20
must be specified or default to "true" for fields of primitive types,=20
wrappers, java.lang, java.math, java.util, collection, map, and array types=
=20
specified above; and =E2=80=9Cfalse=E2=80=9D otherwise. Thus, specifying th=
is attribute is=20
not usually necessary. While a compliant implementation is permitted to=20
support these types as first class instances in the datastore, the semantic=
s=20
of embedded=3D=E2=80=9Dtrue=E2=80=9D imply containment. That is, the embedd=
ed instances have no=20
independent existence in the datastore and have no Extent representation.
</spec>

Depends if it means the "java.lang, java.math, ... types specified above" (=
i.e=20
all of the specific types specified above), or if it means "array types=20
specified above" (just the last part applying to the "specified above").=20
Since I've got a teaching qualification in English, I'm opting for the=20
latter, but maybe our local spec author can clarify the intent ;-)

=2D-=20
Andy

Sponsored Links






Free braindumps | Software forum | Database administration forum

Copyright 2003 - 2008 webservertalk.com