<s>
Java	B-Language
Data	I-Language
Objects	I-Language
(	O
JDO	O
)	O
is	O
a	O
specification	O
of	O
Java	B-Language
object	B-Application
persistence	I-Application
.	O
</s>
<s>
One	O
of	O
its	O
features	O
is	O
a	O
transparency	O
of	O
the	O
persistence	B-Application
services	O
to	O
the	O
domain	B-Application
model	I-Application
.	O
</s>
<s>
JDO	O
persistent	O
objects	O
are	O
ordinary	O
Java	B-Language
programming	I-Language
language	I-Language
classes	O
(	O
POJOs	B-Language
)	O
;	O
there	O
is	O
no	O
requirement	O
for	O
them	O
to	O
implement	O
certain	O
interfaces	B-Language
or	O
extend	O
from	O
special	O
classes	O
.	O
</s>
<s>
JDO	O
1.0	O
was	O
developed	O
under	O
the	O
Java	B-Language
Community	I-Language
Process	I-Language
as	O
.	O
</s>
<s>
Object	B-Application
persistence	I-Application
is	O
defined	O
in	O
the	O
external	O
XML	B-Protocol
metafiles	O
,	O
which	O
may	O
have	O
vendor-specific	O
extensions	O
.	O
</s>
<s>
JDO	O
vendors	O
provide	O
developers	O
with	O
enhancers	O
,	O
which	O
modify	O
compiled	O
Java	B-Language
class	O
files	B-Operating_System
so	O
they	O
can	O
be	O
transparently	O
persisted	O
.	O
</s>
<s>
Currently	O
,	O
JDO	O
vendors	O
offer	O
several	O
options	O
for	O
persistence	B-Application
,	O
e.g.	O
</s>
<s>
to	O
RDBMS	B-Application
,	O
to	O
OODB	B-Application
,	O
or	O
to	O
files	B-Operating_System
.	O
</s>
<s>
Once	O
enhanced	O
,	O
a	O
Java	B-Language
class	O
can	O
be	O
used	O
with	O
any	O
vendor	O
's	O
JDO	O
product	O
.	O
</s>
<s>
JDO	O
is	O
integrated	O
with	O
Java	B-Language
EE	I-Language
in	O
several	O
ways	O
.	O
</s>
<s>
Secondly	O
,	O
JDO	O
may	O
work	O
in	O
the	O
context	O
of	O
JEE	O
transaction	B-Language
services	I-Language
.	O
</s>
<s>
Enterprise	B-Language
JavaBeans	I-Language
3.0	O
(	O
EJB3	O
)	O
specification	O
also	O
covered	O
persistence	B-Application
,	O
as	O
had	O
EJB	B-Language
v2	O
with	O
Entity	B-Language
Beans	I-Language
.	O
</s>
<s>
In	O
the	O
end	O
,	O
persistence	B-Application
has	O
been	O
"	O
broken	O
out	O
"	O
of	O
"	O
EJB3	O
Core	O
"	O
,	O
and	O
a	O
new	O
standard	O
formed	O
,	O
the	O
Java	B-Language
Persistence	I-Language
API	I-Language
(	O
JPA	O
)	O
.	O
</s>
<s>
JPA	O
uses	O
the	O
javax.persistence	O
package	O
,	O
and	O
was	O
first	O
specified	O
in	O
a	O
separate	O
document	O
within	O
the	O
EJB3	O
spec	O
,	O
but	O
was	O
later	O
moved	O
to	O
its	O
own	O
spec	O
.	O
</s>
<s>
Significantly	O
,	O
javax.persistence	O
will	O
not	O
require	O
an	O
EJB	B-Language
container	I-Language
,	O
and	O
thus	O
will	O
work	O
within	O
a	O
Java	B-Language
SE	O
environment	O
as	O
well	O
,	O
as	O
JDO	O
always	O
has	O
.	O
</s>
<s>
JPA	O
,	O
however	O
,	O
is	O
an	O
object-relational	B-General_Concept
mapping	I-General_Concept
(	O
ORM	O
)	O
standard	O
,	O
while	O
JDO	O
is	O
both	O
an	O
object-relational	B-General_Concept
mapping	I-General_Concept
standard	O
and	O
a	O
transparent	O
object	B-Application
persistence	I-Application
standard	O
.	O
</s>
<s>
JDO	O
,	O
from	O
an	O
API	O
point	O
of	O
view	O
,	O
is	O
agnostic	O
to	O
the	O
technology	O
of	O
the	O
underlying	O
datastore	O
,	O
whereas	O
JPA	O
is	O
targeted	O
to	O
RDBMS	B-Application
datastores	O
(	O
although	O
there	O
are	O
several	O
JPA	O
providers	O
that	O
support	O
access	O
to	O
non-relational	O
datastores	O
through	O
the	O
JPA	O
API	O
,	O
such	O
as	O
DataNucleus	B-Application
and	O
ObjectDB	B-Operating_System
)	O
.	O
</s>
<s>
Leading	O
JDO	O
commercial	O
implementations	O
and	O
open	O
source	O
projects	O
also	O
offer	O
a	O
JPA	O
API	O
implementation	O
as	O
an	O
alternative	O
access	O
to	O
their	O
underlying	O
persistence	B-Application
engines	O
,	O
formerly	O
exposed	O
solely	O
via	O
JDO	O
in	O
the	O
original	O
products	O
.	O
</s>
