hibernate-devel — development

RE: [Hibernate-devel] SQL Server 2000 questions

[Donnie H. <do...@ha...>]

I'm pretty handy w/ Ant these days. If I can get the current environment
(maybe directly from CVS), I can look and see where things stand.

No promises, as I'm really swamped; plus this is mid-soccer season for my
boys. ;)

Donnie


> -----Original Message-----
> From: hib...@li...
> [mailto:hib...@li...]On Behalf Of
> Gavin_King/Cirrus%CI...@ci...
> Sent: Sunday, April 14, 2002 9:58 PM
> To: Brad Clow
> Cc: hib...@li...
> Subject: RE: [Hibernate-devel] SQL Server 2000 questions
>
>
>
>
> > gavin, if hibernate is sticking with the one distribution (classes and
> > source together) then i think the user should be able change the code
> > and rebuild the distribution easily.    to achieve this the ant script
> > should be included and possibly the libs.  if u wanted to tidy this
> > aspect of the project up using ant as the one build tool, i can
> > certainly give u a hand.  also, the java source is currently included in
> > the jar.
>
> building distributions is a hassle for me at the moment. Any help would be
> very appreciated. And your suggestions are quite correct, of course.
>
> > i agree that writing bean-style property methods is tedious, but it is a
> > task than can be fairly easily automated.
>
> Im using eclipse so its trivial. I really like the whole idea of
> decoupling
> the persistent representation from the internal implementation.
> But I guess
> its a matter of preference, so since theres no difficulty implemention
> instance variable access, why not allow it?
>
>
> _______________________________________________
> Hibernate-devel mailing list
> Hib...@li...
> https://lists.sourceforge.net/lists/listinfo/hibernate-devel
>

RE: [Hibernate-devel] SQL Server 2000 questions

[Anton v. S. <an...@ap...>]

> But yeah, support for instance variable access never went in so
> far, simply because it seemed like it would support a "worse"
> coding style. Now I'm sounding real indecisive, huh? :)

When in doubt, procrastinate?  :)

To add a decision factor: if it could be added as a feature without any
cost, maybe some people would find that useful (although not me).  But even
if it only takes an hour of your time to implement, there are other costs:
documenting it, explaining why it shouldn't really be used, adding choices
which the user needs to understand and take into consideration.  Choice is
good if it provides important flexibility, but in this case it seems like it
would fall more on the side of gratuitous bloat.

BTW, I realize my argument may seem overly impassioned for an arguably minor
issue, and if you add the feature anyway, I won't really mind.  But when I
said "don't give up your principles so easily", I was thinking of one of the
features which attracted me to Hibernate in the first place: it seems to
have almost everything I need, and very little I don't, and it works the way
I expect it to.  I don't get the same feeling when I use EJB frameworks, for
example - which is why I avoid them when I can.  Limiting user choice can be
a good thing...

Anton

RE: [Hibernate-devel] SQL Server 2000 questions

[Gavin_King/Cirrus%<CI...@ci...>]

>  I'm saying that the requirement raised by Donnie - which I think I
> share - doesn't seem to really be solved by adding instance variable
> support.

Sorry, I may have given the impression I was missing the main point, which
is that people want to be able to do "bottom-up" style development as well
as "top-down" style. I fully understand the importance of this. But the
comment about generating properties being tedious got me thinking
tangentially about people using vi or emacs or something.....

But yeah, support for instance variable access never went in so far, simply
because it seemed like it would support a "worse" coding style. Now I'm
sounding real indecisive, huh? :)

RE: [Hibernate-devel] SQL Server 2000 questions

[Anton v. S. <an...@ap...>]

> > i agree that writing bean-style property methods is tedious, but it is a
> > task than can be fairly easily automated.
>
> Im using eclipse so its trivial.

I'm using Eclipse too, but it doesn't automate the creation of a large
number of beans from an existing database schema - does it?

> I really like the whole idea of decoupling
> the persistent representation from the internal implementation.

Me too.

> But I guess its a matter of preference

Don't give up your principles so easily!  ;)

> so since theres no difficulty implemention
> instance variable access, why not allow it?

My question would be: why allow it?

The issue for me isn't Hibernate's reliance on setters/getters - it's really
a more general concern, which is that if schema and mapping information is
stored in three different places, then synchronizing them could become
tedious, and error prone.

I'm speaking theoretically because I haven't used Hibernate enough to know
how important this might be in practice.  I realize that if you rely on the
beans as the central source for schema info, and can rely on
MappingByReflection to get the mapping you want, then the problem I'm
thinking of wouldn't exist.  However, with an existing database, it looks to
me as though it may not be that easy.  So I'm looking at dealing with manual
edits to the mapping XML, then synchronizing the beans with that, and
synchronizing changes in the database too.

Supporting instance variable access slightly reduces the number of places
that are affected by schema changes, but as has been mentioned, property
methods are easily automated, but the basic synchronization issue still
exists.  Besides, instance variable access would allow users to use non-bean
classes, but that only seems to encourage the writing of bad code - what's
the real advantage?

So I'm saying that the requirement raised by Donnie - which I think I
share - doesn't seem to really be solved by adding instance variable
support.  It seems to me that we haven't heard any really good arguments for
doing that.  (Course, I've only been subscribed to the list for 6 messages,
so add salt to taste... ;)

Anton

RE: [Hibernate-devel] SQL Server 2000 questions

[Gavin_King/Cirrus%<CI...@ci...>]

> gavin, if hibernate is sticking with the one distribution (classes and
> source together) then i think the user should be able change the code
> and rebuild the distribution easily.    to achieve this the ant script
> should be included and possibly the libs.  if u wanted to tidy this
> aspect of the project up using ant as the one build tool, i can
> certainly give u a hand.  also, the java source is currently included in
> the jar.

building distributions is a hassle for me at the moment. Any help would be
very appreciated. And your suggestions are quite correct, of course.

> i agree that writing bean-style property methods is tedious, but it is a
> task than can be fairly easily automated.

Im using eclipse so its trivial. I really like the whole idea of decoupling
the persistent representation from the internal implementation. But I guess
its a matter of preference, so since theres no difficulty implemention
instance variable access, why not allow it?

Re: [Hibernate-devel] schema generation

[Gavin_King/Cirrus%<CI...@ci...>]

> A full set round-trip tools that can propagate changes from the classes
to
> the mapping to the database (in arbitrary sequence :) would be great.
The
> easiest to implement is probably the one which goes from Hibernate's XML
to
> bean skeletons - that's pretty trivial.  If such a tool doesn't already
> exist and no-one gets to it before me, I'll probably implement that.

I would love to have a toolset like that. Hopefully we can build it
piece-by piece.

RE: [Hibernate-devel] SQL Server 2000 questions

[Gavin_King/Cirrus%<CI...@ci...>]

> I was able to figure out how to run FooBarTest. After setting the proper
> "SelectMethod=cursor" parameter in the URL, I was able to run a large
number
> of the tests. Here are a couple of the issues I encountered:

Sorry, I should have mentioned the SelectMethod=cursor bit. Its very
important.

> In testLoad there was a NPE, though the program kept running:

Dont worry, the NPE is intended as a test.

> In testQuery, there was this exception:

> testQuery...
> Exception in thread "main" java.lang.reflect.InvocationTargetException
>        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

[snip]

>I couldn't quite figure out what was underlying this issue. You'll note
from
>the "... 6 more" line that this was under JDK 1.4. It was with the 0.9.8
>release.

Urrghhh thats an unhelpful looking stacktrace. I might mess with TestCase
to unwrap the wrapped exception. Been meaning to do that for a while.
Alternatively I could switch to JUnit which everyone else seems to be in
favor of.....

I have looked at this problem in the past but I forget exactly what the
root cause was. I did verify that it was something I couldn't easily
fix....

It would be very nice if we can establish exactly which subset of
hibernate's functionality is working using the MS driver. It might turn out
to be a large enough subset for some people's requirements.

> A couple of other comments, most of which you probably know:

> 1) The sybase dialect really isn't appropriate for SQL Server 2000. SS2K
has
> data types that a lot more directly map to the java.sql.Types (e.g. bit
to
> BIT, bigint to BIGINT, etc.).

Thankyou for letting me know this. Would you like to write an MSSQLDialect
for us? You seem to know the platform much better than me.

> 2) In trying to workaround one problem, I had to change some hibernate
code
> (nothing permanent). The lack of a build facility meant I had to cobble
> together a batch file to do that. A nice Ant script would be great (maybe
I
> missed something in the download).

Try checking out the latest CVS. (There are also some improvements/fixes in
there that I really should have released weeks ago - been so busy)

> 3) This is more of a philosophical thing. I agree quite fully about the
> reflection-based approach to mapping. However, I tend to think that the
DB
> should be the authority when it comes to the schema, not the app or a
.xml
> file. This is primarily because the things that one can specify about the
> schema in, for example, Enterprise Manager start getting fairly
> database-specific (constraints, triggers, etc.); and they aren't
necessarily
> important to represent in the .xml file. So I tend to start in the
database
> and try to take as much advantage as possible of its capabilities to
> declaratively define the schema and the rules for enforcing data
integrity.

Can you give me a better idea of exactly how you would divide
responsibility here. It sort of seems to me that _schemas_ are easy things
to keep in the database but _mappings_ not so easy.... One intended
approach is to define all schemas on the DB and use the mapping file as a
map _only_. You dont need to use the schema generation tool. I'm very open
to new ideas on all this....

> Another point is that writing bean-style property methods on a class is
> excruciatingly tedious.

Aaahhhh ... being an IDE-user I probably underestimate the pain in this for
some people. You know, it would be about an hours work to let hibernate use
also instance variables directly. Would anyone like this?

> What I'm getting at is that I'd like to see a
> generator facility to go from the schema to the .xml and from the .xml to
> the skeleton of the bean classes. It wouldn't need to be a required
> capability to use Hibernate, more of an optional facility like the
current
> schema generator.

That would be nice. If anyone wants to contribute something like that we
should certainly include it.

> Just one man's opinion...

Which is very welcome :)

peace

Gavin




> -----Original Message-----
> From: Gavin_King/Cirrus%CI...@ci...
> [mailto:Gavin_King/Cirrus%CI...@ci...]
> Sent: Saturday, April 13, 2002 9:12 PM
> To: Donnie Hale
> Cc: hib...@li...
> Subject: RE: [Hibernate-devel] SQL Server 2000 questions
>
>
>
> > Don't know if/when you'll get this, but thought I'd send it while I go
> off
> > and look  into things.
>
> > Are there instructions, or can you point me in the right direction, to
> run
> > the test suite against a particular JDBC driver / database? I
> want to run
> it
> > against SQL Server 2K w/ the MS JDBC driver just to see what I
discover.
>
> The class cirrus.hibernate.test.FooBarTest is executable. Run it with
> "mssql" as a command line argument.
>
> Hope thats enough to get you started. Any problems let me know.
>
> peace
>
> Gavin
>
>

RE: [Hibernate-devel] SQL Server 2000 questions

[Brad C. <bra...@wo...>]

hi donnie

get the cvs version.  it has an ant build script that enables u to
compile, javadoc, test, etc.

gavin, if hibernate is sticking with the one distribution (classes and
source together) then i think the user should be able change the code
and rebuild the distribution easily.    to achieve this the ant script
should be included and possibly the libs.  if u wanted to tidy this
aspect of the project up using ant as the one build tool, i can
certainly give u a hand.  also, the java source is currently included in
the jar.

on your philosophical topic (and each to his/her own here), i work the
opposite way (even after being a dba somewhere in the dim, dark past).
i find it much more intuitive and less time consuming to work at the
object level, since that is what all my code that implements the
application's logic is directly manipulating.  how those objects are
persisted is then not the most important thing.  having said that, i do
go and check/tweak the schema to ensure integrity and performance.  just
my thoughts, like i said, each to there own.

i agree that writing bean-style property methods is tedious, but it is a
task than can be fairly easily automated.

brad

> -----Original Message-----
> From: Donnie Hale [mailto:do...@ha...]
> Sent: Monday, 15 April 2002 5:13 AM
> To: hib...@li...
> Subject: RE: [Hibernate-devel] SQL Server 2000 questions
>=20
>=20
> Gavin,
>=20
> Thanks for responding.
>=20
> I was able to figure out how to run FooBarTest. After setting=20
> the proper
> "SelectMethod=3Dcursor" parameter in the URL, I was able to run=20
> a large number
> of the tests. Here are a couple of the issues I encountered:
>=20
> In testLoad there was a NPE, though the program kept running:
>=20
> testLoad...
> java.lang.NullPointerException
>         at
> cirrus.hibernate.impl.RelationalDatabaseSession$Key.hashCode(R
> elationalDatab
> aseSession.java:183)
>         at java.util.HashMap.hash(HashMap.java:250)
>         at java.util.HashMap.get(HashMap.java:301)
>         at
> cirrus.hibernate.impl.RelationalDatabaseSession.save(Relationa
> lDatabaseSessi
> on.java:464)
>         at
> cirrus.hibernate.impl.RelationalDatabaseSession.insert(Relatio
> nalDatabaseSes
> sion.java:445)
>         at=20
> cirrus.hibernate.test.FooBarTest.testLoad(FooBarTest.java:178)
>         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>         at
> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccess
> orImpl.java:39
> )
>         at
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMeth
> odAccessorImpl
> .java:25)
>         at java.lang.reflect.Method.invoke(Method.java:324)
>         at cirrus.hibernate.test.TestCase.run(TestCase.java:46)
>         at cirrus.hibernate.test.FooBarTest.main(FooBarTest.java:1217)
>=20
> In testQuery, there was this exception:
>=20
> testQuery...
> Exception in thread "main" java.lang.reflect.InvocationTargetException
>         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>         at
> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccess
> orImpl.java:39
> )
>         at
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMeth
> odAccessorImpl
> .java:25)
>         at java.lang.reflect.Method.invoke(Method.java:324)
>         at cirrus.hibernate.test.TestCase.run(TestCase.java:46)
>         at cirrus.hibernate.test.FooBarTest.main(FooBarTest.java:1217)
> Caused by: java.lang.Exception: component query
>         at cirrus.hibernate.test.TestCase.assertTrue(TestCase.java:66)
>         at=20
> cirrus.hibernate.test.FooBarTest.testQuery(FooBarTest.java:323)
>         ... 6 more
>=20
> I couldn't quite figure out what was underlying this issue.=20
> You'll note from
> the "... 6 more" line that this was under JDK 1.4. It was=20
> with the 0.9.8
> release.
>=20
> A couple of other comments, most of which you probably know:
>=20
> 1) The sybase dialect really isn't appropriate for SQL Server=20
> 2000. SS2K has
> data types that a lot more directly map to the java.sql.Types=20
> (e.g. bit to
> BIT, bigint to BIGINT, etc.).
>=20
> 2) In trying to workaround one problem, I had to change some=20
> hibernate code
> (nothing permanent). The lack of a build facility meant I had=20
> to cobble


> _______________________________
> brad clow
> chief technical officer
> workingmouse
>=20
> email: bra...@wo...
> web:   http://www.workingmouse.com
>=20

[Hibernate-devel] schema generation

[Anton v. S. <an...@ap...>]

Donnie Hale wrote:
> Another point is that writing bean-style property methods on a
> class is excruciatingly tedious.  What I'm getting at is that
> I'd like to see a generator facility to go from the schema to
> the .xml and from the .xml to the skeleton of the bean classes.
> It wouldn't need to be a required capability to use Hibernate,
> more of an optional facility like the current schema generator.

I'll second that.  I've just begun using Hibernate (I'm very impressed with
it, BTW!) and this is one of the first requirements I ran into.

In the first project I'm using it on, what I'm doing to deal with the above
issue is a little perverse, but it's working for my purposes so far: I wrote
some code to generate the bean skeletons from my database schema.  This was
pretty simple to do given that I was able to make assumptions about this
particular system and database, and even naming conventions, in order to
come up with a decent set of bean skeletons.  I then used Hibernate's
MappingByReflection class to generate a Hibernate XML mapping.  This has
worked pretty well for me as a starting point, but it's by no means general
or complete.

A full set round-trip tools that can propagate changes from the classes to
the mapping to the database (in arbitrary sequence :) would be great.  The
easiest to implement is probably the one which goes from Hibernate's XML to
bean skeletons - that's pretty trivial.  If such a tool doesn't already
exist and no-one gets to it before me, I'll probably implement that.

> I tend to think that the DB should be the authority when it comes to the
schema

I'm guessing most Hibernate users are using their Java classes as the master
source of schema information, otherwise the tools we're looking for would
already exist...  ;)

Anton

RE: [Hibernate-devel] SQL Server 2000 questions

[Donnie H. <do...@ha...>]

Gavin,

Thanks for responding.

I was able to figure out how to run FooBarTest. After setting the proper
"SelectMethod=cursor" parameter in the URL, I was able to run a large number
of the tests. Here are a couple of the issues I encountered:

In testLoad there was a NPE, though the program kept running:

testLoad...
java.lang.NullPointerException
        at
cirrus.hibernate.impl.RelationalDatabaseSession$Key.hashCode(RelationalDatab
aseSession.java:183)
        at java.util.HashMap.hash(HashMap.java:250)
        at java.util.HashMap.get(HashMap.java:301)
        at
cirrus.hibernate.impl.RelationalDatabaseSession.save(RelationalDatabaseSessi
on.java:464)
        at
cirrus.hibernate.impl.RelationalDatabaseSession.insert(RelationalDatabaseSes
sion.java:445)
        at cirrus.hibernate.test.FooBarTest.testLoad(FooBarTest.java:178)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39
)
        at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
        at java.lang.reflect.Method.invoke(Method.java:324)
        at cirrus.hibernate.test.TestCase.run(TestCase.java:46)
        at cirrus.hibernate.test.FooBarTest.main(FooBarTest.java:1217)

In testQuery, there was this exception:

testQuery...
Exception in thread "main" java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39
)
        at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
        at java.lang.reflect.Method.invoke(Method.java:324)
        at cirrus.hibernate.test.TestCase.run(TestCase.java:46)
        at cirrus.hibernate.test.FooBarTest.main(FooBarTest.java:1217)
Caused by: java.lang.Exception: component query
        at cirrus.hibernate.test.TestCase.assertTrue(TestCase.java:66)
        at cirrus.hibernate.test.FooBarTest.testQuery(FooBarTest.java:323)
        ... 6 more

I couldn't quite figure out what was underlying this issue. You'll note from
the "... 6 more" line that this was under JDK 1.4. It was with the 0.9.8
release.

A couple of other comments, most of which you probably know:

1) The sybase dialect really isn't appropriate for SQL Server 2000. SS2K has
data types that a lot more directly map to the java.sql.Types (e.g. bit to
BIT, bigint to BIGINT, etc.).

2) In trying to workaround one problem, I had to change some hibernate code
(nothing permanent). The lack of a build facility meant I had to cobble
together a batch file to do that. A nice Ant script would be great (maybe I
missed something in the download).

3) This is more of a philosophical thing. I agree quite fully about the
reflection-based approach to mapping. However, I tend to think that the DB
should be the authority when it comes to the schema, not the app or a .xml
file. This is primarily because the things that one can specify about the
schema in, for example, Enterprise Manager start getting fairly
database-specific (constraints, triggers, etc.); and they aren't necessarily
important to represent in the .xml file. So I tend to start in the database
and try to take as much advantage as possible of its capabilities to
declaratively define the schema and the rules for enforcing data integrity.

Another point is that writing bean-style property methods on a class is
excruciatingly tedious. What I'm getting at is that I'd like to see a
generator facility to go from the schema to the .xml and from the .xml to
the skeleton of the bean classes. It wouldn't need to be a required
capability to use Hibernate, more of an optional facility like the current
schema generator.

Just one man's opinion...

Thanks again,

Donnie





> -----Original Message-----
> From: Gavin_King/Cirrus%CI...@ci...
> [mailto:Gavin_King/Cirrus%CI...@ci...]
> Sent: Saturday, April 13, 2002 9:12 PM
> To: Donnie Hale
> Cc: hib...@li...
> Subject: RE: [Hibernate-devel] SQL Server 2000 questions
>
>
>
> > Don't know if/when you'll get this, but thought I'd send it while I go
> off
> > and look  into things.
>
> > Are there instructions, or can you point me in the right direction, to
> run
> > the test suite against a particular JDBC driver / database? I
> want to run
> it
> > against SQL Server 2K w/ the MS JDBC driver just to see what I discover.
>
> The class cirrus.hibernate.test.FooBarTest is executable. Run it with
> "mssql" as a command line argument.
>
> Hope thats enough to get you started. Any problems let me know.
>
> peace
>
> Gavin
>
>

RE: [Hibernate-devel] SQL Server 2000 questions

[Gavin_King/Cirrus%<CI...@ci...>]

> Don't know if/when you'll get this, but thought I'd send it while I go
off
> and look  into things.

> Are there instructions, or can you point me in the right direction, to
run
> the test suite against a particular JDBC driver / database? I want to run
it
> against SQL Server 2K w/ the MS JDBC driver just to see what I discover.

The class cirrus.hibernate.test.FooBarTest is executable. Run it with
"mssql" as a command line argument.

Hope thats enough to get you started. Any problems let me know.

peace

Gavin

RE: [Hibernate-devel] SQL Server 2000 questions

[Donnie H. <do...@ha...>]

Don't know if/when you'll get this, but thought I'd send it while I go off
and look  into things.

Are there instructions, or can you point me in the right direction, to run
the test suite against a particular JDBC driver / database? I want to run it
against SQL Server 2K w/ the MS JDBC driver just to see what I discover.

Many thanks,

Donnie Hale


> -----Original Message-----
> From: hib...@li...
> [mailto:hib...@li...]On Behalf Of
> Gavin_King/Cirrus%CI...@ci...
> Sent: Saturday, March 16, 2002 8:30 PM
> To: Donnie Hale
> Cc: hib...@li...
> Subject: Re: [Hibernate-devel] SQL Server 2000 questions
>
>
>
> The one I have been using is JSQL from:
>
> http://www.j-netdirect.com/
>
> This particular driver seems to work beautifully.
>
> I have just verified that Weblogic jDriver also works (with one very minor
> test failure).
>
> FreeTDS certainly does *not* work. I _think_ someone reported that
>
> http://www.inetsoftware.de/
>
> also does *not* work. (Havn't tried this myself)
>
> The latest version of Microsoft's driver doesn't pass all tests, but it
> does pass *some*. It might be almost possible to get it working, but I'm
> not particularly optimistic. (If you want to try, you _must_ use the
> SelectMethod=cursor JDBC connection parameter.)
>
> Good Luck
>
> Gavin
>
>
> _______________________________________________
> Hibernate-devel mailing list
> Hib...@li...
> https://lists.sourceforge.net/lists/listinfo/hibernate-devel
>

Re: [Hibernate-devel] Problems with Component property (with 0.9.8)

[Phillip B. <phi...@cl...>]

Thanks for the speedy solution Gavin.

Will give it go.

PhillipB.

Gavin_King/Cirrus%CI...@ci... wrote:

>
>The bug is now fixed in CVS.
>
>Enjoy !
>
>

Re: [Hibernate-devel] Problems with Component property (with 0.9.8)

[Gavin_King/Cirrus%<CI...@ci...>]

The bug is now fixed in CVS.

Enjoy !

Re: [Hibernate-devel] Problems with Component property (with 0.9.8)

[Gavin_King/Cirrus%<CI...@ci...>]

Thanks for that Philip - I see the bug: nullifyTransientReferences() should
check if the component is null before grabbing its properties. I will add a
test and fix the bug in CVS ASAP (tomorrow).

sorry for my slow ping-time I have been camping in Tasmania for last few
days.

peace

Gavin

[Hibernate-devel] Problems with Component property (with 0.9.8)

[Phillip B. <phi...@cl...>]

Gidday all,

I'm having endless problems trying to do what I thought would be a 
no-brainer exercise with a Component property.

Basically my classes are like the Person -> Name compoent example in the 
tutorial doc.  I have a Listing class which contains a PhoneNumber 
property.  PhoneNumber simply has four String properties which are 
mapped to the Listing class's table.  So my mapping looks like this...

  <class name="phonebook.model.Listing" table="Listing" select="distinct">
    <id name="UID" type="long" column="UID">
      <generator class="hilo.long"/>
    </id>
    <property name="name" column="name" type="string"/>
    <component name="businessNumber" class="phonebook.model.PhoneNumber">
        <property name="countryCode" column="countryCode" type="string"/>
        <property name="areaCode" column="areaCode" type="string"/>
        <property name="phoneNumber" column="phoneNumber" type="string"/>
        <property name="extension" column="extension" type="string"/>
    </component>

If I try to save a Listing the following exception is thrown...

java.lang.NullPointerException
        at java.lang.reflect.Method.invoke(Native Method)
        at 
cirrus.hibernate.type.ComponentType.getPropertyValue(ComponentType.java:152)
        at 
cirrus.hibernate.type.ComponentType.getValues(ComponentType.java:171)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.nullifyTransientReferences(RelationalDatabaseSession.java:527)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.nullifyTransientReferences(RelationalDatabaseSession.java:517)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.save(RelationalDatabaseSession.java:484)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.save(RelationalDatabaseSession.java:434)
        at phonebook.model.ListingFactory.save(ListingFactory.java:125)

This exception is being caused because Listing.getBusinessNumber() is 
returning a null.  Ok so I thought I'd work around the problem by 
initialising the property in the default constructor.  That worked.   
Now the Listing could be saved.  Tried deleting it next using 
session.delete("FROM listing IN CLASS phonebook.model.Listing") and got 
the following similar exception...

java.lang.NullPointerException
        at java.lang.reflect.Method.invoke(Native Method)
        at 
cirrus.hibernate.type.ComponentType.getPropertyValue(ComponentType.java:152)
        at 
cirrus.hibernate.type.ComponentType.getValues(ComponentType.java:171)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.nullifyTransientReferences(RelationalDatabaseSession.java:527)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.nullifyTransientReferences(RelationalDatabaseSession.java:517)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.delete(RelationalDatabaseSession.java:590)
        at 
cirrus.hibernate.impl.IdentifierIterator.remove(IdentifierIterator.java:116)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.delete(RelationalDatabaseSession.java:669)
        at 
cirrus.hibernate.impl.RelationalDatabaseSession.delete(RelationalDatabaseSession.java:651)
        at phonebook.model.ListingFactory.deleteAll(ListingFactory.java:67)

Running up the debugger I could see the Iterator was returning the 
Listing that had been saved.  As documented in the tutorial doc, because 
all the PhoneNumber properties were blank, the businessNumber property 
ended up being set to null when loaded.  This then resulted in same 
exception as when saving.

So after all that my question is - is this a bug?  How should null 
Component properties be handled?

thanks

PhillipB

Re: [Hibernate-devel] bug in hibernate-0.9.8

[Sven W. <s_...@in...>]

>     private Connection getConnection();
>     private Session getHibernateSession()
>     {
>         Session s = null;
>         try
>         {
>             Datastore ds =
> Hibernate.createDatastore();
>             ds =
> ds.storeFile("/home/son/mapping.xml");
>             SessionFactory sessionFactory =
> ds.buildSessionFactory();
>             Connection conn = getConnection();
>             s = sessionFactory.openSession(conn);
>         }
>         catch (Exception ex)
>         {
>             ex.printStackTrace();
>         }
>         return s;
>     }
>
> ----end---
> The EJB container I'm using is JBoss2.4.4 and the
> database is postgresql7.1
  [...]
> This happens when I connect to the bean 32 times. It
> seems hibernate is not releasing the Connection even
> though I did a session.close(). When I try to connect
> to postgres directly using JDBC, I get
>
> Exception: java.sql.SQLException: Sorry, too many
> clients already
>
It's not a but it's a feature ;-)
Somewhere is the docs is written:
If you supply a connection (you _are_ doing this with openSession
(your_CONNECTION!)) _you_ have to be responsible for closing the
connection. Hibernate will only close connections that where created
directly by hibernate.

BTW:
- If you're using JBoss you can set the connection pooling to
  "blocking" if there are no free connections left.
- If you're coding in a J2EE environment your beans should not access the
  filesystem in a direct way (it is possible to load the mapping file via
  class.getRessource (...))

HTH
  Sven

--
Planung bedeutet den Zufall durch den Irrtum zu ersetzten.

[Hibernate-devel] bug in hibernate-0.9.8

[Son To <son...@ya...>]

I'm testing out hibernate-0.9.8 and there seems to be
a bug. Here is the code to the relevant code in
stateless session bean:
--start-----
    public List findAllProduct()
    {
        Session session = getHibernateSession();
        List productList = null;
        try
        {
            productList = session.find("select product
from product in class openbx.domain.Product");
            session.close();
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }
        return productList;
    }

    private Connection getConnection()
    {
        ServiceLocator sL =
ServiceLocator.getInstance();
        Connection conn = null;
        try
        {
            DataSource ds =
(DataSource)sL.lookup(sL.JDBC_DATASOURCE);
            conn = ds.getConnection();
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }
        return conn;
    }

    private Session getHibernateSession()
    {
        Session s = null;
        try
        {
            Datastore ds =
Hibernate.createDatastore();
            ds =
ds.storeFile("/home/son/mapping.xml");
            SessionFactory sessionFactory =
ds.buildSessionFactory();
            Connection conn = getConnection();
            s = sessionFactory.openSession(conn);
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }
        return s;
    }

----end---
The EJB container I'm using is JBoss2.4.4 and the
database is postgresql7.1

Here is Jboss error log:
[ERROR,Default] java.lang.NullPointerException
[ERROR,Default] 	at
org.jboss.pool.jdbc.xa.XAPoolDataSource.getConnection(Unknown
Source)

...skip
...skip
...skip

[ERROR,Default] java.lang.NullPointerException
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSession.getPreparedStatement(RelationalDatabaseSession.java:1774)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSession.prepareQueryStatement(RelationalDatabaseSession.java:717)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSession.find(RelationalDatabaseSession.java:760)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSession.find(RelationalDatabaseSession.java:710)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSession.find(RelationalDatabaseSession.java:620)

This happens when I connect to the bean 32 times. It
seems hibernate is not releasing the Connection even
though I did a session.close(). When I try to connect
to postgres directly using JDBC, I get

Exception: java.sql.SQLException: Sorry, too many
clients already

So next I attempted to investigate why hibernate is
not releasing the Connection.  I compiled the source
code distributed in  hibernate-0.9.8.tar.gz.
Everything compiled fine, but when I redeployed my
bean using the hibernate.jar compiled from source, I
get a different problem. Here is JBoss error message:

----
[ERROR,Default]
javax.xml.transform.TransformerConfigurationException:
javax.xml.transform.TransformerException:
java.lang.NullPointerException
[ERROR,Default] 	at
org.apache.xalan.processor.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:946)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSessionFactory.<init>(RelationalDatabaseSessionFactory.java:102)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatabaseSessionFactory.<init>(RelationalDatabaseSessionFactory.java:135)
[ERROR,Default] 	at
cirrus.hibernate.impl.RelationalDatastore.buildSessionFactory(RelationalDatastore.java:50)
	at
org.apache.xalan.processor.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:946)
	at
cirrus.hibernate.impl.RelationalDatabaseSessionFactory.<init>(RelationalDatabaseSessionFactory.java:102)
	at
cirrus.hibernate.impl.RelationalDatabaseSessionFactory.<init>(RelationalDatabaseSessionFactory.java:135)
 	at
cirrus.hibernate.impl.RelationalDatastore.buildSessionFactory(RelationalDatastore.java:50)
---

I got the same result when compiling from code in CVS.
 So the question for Gavin is what is the source code
for hibernate.jar that id distributed with
hibernate0.9.8.tar.gz?

thanks,
Son

__________________________________________________
Do You Yahoo!?
Yahoo! Greetings - send holiday greetings for Easter, Passover
http://greetings.yahoo.com/

Re: [Hibernate-devel] datasource jndi config

[Gavin_King/Cirrus%<CI...@ci...>]

Thanks Brad, that looks fine.....

[Hibernate-devel] datasource jndi config

[Brad C. <bra...@wo...>]

currently hibernate requires the setting of a jndi class and jndi url, when
using a datasource.  i would like to make these optional.  to achieve this,
i have modified (but not commited) DatasourceConnectionProvider.java to look
like:

        // we want to be able to just use the defaults, if jndi environment
properties are not supplied
        if (jndi_class != null) {
            hash.put(Context.INITIAL_CONTEXT_FACTORY, jndi_class);
        }

        if (jndi_url != null) {
            hash.put(Context.PROVIDER_URL, jndi_url);
        }

        try {
          ctx = new InitialContext(hash);
          ....

this works fine in the web container i am currently using and fine in jboss.
however i don't know a great deal about jndi, so comments r welcome.  if i
don't hear anything negative over the next day, i will commit this.

thanx

brad

_______________________________
brad clow
chief technical officer
workingmouse

email: bra...@wo...
web:   http://www.workingmouse.com

Re: [Hibernate-devel] SAP DB dialect

[Brad C. <bra...@wo...>]

i just committed the changes to the hilogenerator for quoting the column
name in all sql statements.  i have used double quotes and the tests have
passed both in sap db and oracle.  if double quotes are illegal in one of
the other supported rdbms' perhaps the quote used could be made dialect
specific.

to get around the double problem, i reduced the size of the value that the
double is set to in Foo.java.

i have set alter table support to false, to get around the syntax problems
with the alter table statements generated in the schema export.  this is a
lower priority for me at the moment than some other things, so i won't get
to look at this for perhaps a week or so.

sequences are supported.  i will add support for them to the dialect
today/tommorrow.

brad

----- Original Message -----
From: <Gavin_King/Cirrus%CI...@ci...>
To: "Brad Clow" <bra...@wo...>
Cc: <hib...@li...>
Sent: Saturday, March 23, 2002 10:21 AM
Subject: Re: [Hibernate-devel] SAP DB dialect


>
> > i have just commited the sap db dialect to cvs.
>
> Excellent! Thanks Brad. :)
>
> > gavin, r u still happy for me to change the default column name for the
> > hilogenerator from next to next_hi (sap db gets upset when
DBSchemaExport
> > tries to create the hibernate_unique_key table with a column name of
> next,
> > as it is a reserved word)?
>
> When we discussed this earlier other people seemed to prefer that we try
> using quoted "next". If we can get that working with all platforms its
> probably preferable. Can you try it out with SAP, please?
>
> > the test suite fails on testCreateUpdate due to the size of the double
in
> > Foo.java.  sap db seems to support to +1e-64, but Foo's double is set to
> > 1.33e-69, so the exponent seems to large to me.  however the jdbc driver
> > appears to reduce it even more.  i could only get to 1.33e-36 for the
> test
> > to be successful.  i will send a message to the sapdb mailing list about
> > this.
>
> Interbase also has a problem like this, i think. I got round it by
> disabling
> part of the test. Thats a bit of a crude approach, I guess. Anyways,
either
> change or disable the test if you like, whatever works....
>
> Have you got the schema export working? Someone else reported that the
> "alter table add constraint" syntax is not supported by SAP DB so do
> we need to support alternative forms in Dialect?
>
> Does SAP support sequences or identity columns?
>
>
>

Re: [Hibernate-devel] XML databinding.

[Christoph S. <ch...@sc...>]

>
>
>
>Basically, when I got round to implementing this, I
>had a look around and discovered that the open source
>solutions for databinding had improved a whole lot
>and I didn't want to try and waste time doing what
>other people are doing better
>
What open source stuff did you look at? Can you recommend something?

RE: [Hibernate-devel] XML databinding.

[Donnie H. <do...@ha...>]

>
> If I was redoing this from scratch I would take a close look
> at using JAXB or something similar for parsing the mapping
> file.
>

FWIW, the Jakarta Commons "Digester" project might be very appropriate for
this kind of XML-file parsing. You create a digester, give it the rules it
should follow when it encounters elements of various types, and then tell it
to go. At the end, you have an object graph representing the XML. Tomcat and
Struts use it to parse their config files.

FWIW...

Donnie

Re: [Hibernate-devel] XML databinding.

[Gavin_King/Cirrus%<CI...@ci...>]

> Why was JDom chosen as the XML toolkit of choice?  I
> think using Dom4J or something else that supports
> XPath would make life much easier in the mapping file.

Actually to parse mapping files (DOCTYPE hibernate-mapping.dtd)
I'm using vanilla JAXP. This was probably a mistake. JDOM
is used to construct XML representation of persistent objects.
Don't think XPATH would help us here. I've never used DOM4J.
Is it better than JDOM in other ways?

If I was redoing this from scratch I would take a close look
at using JAXB or something similar for parsing the mapping
file.

> I am currently working on an XML mapping system where
> I work (specific use) and am wondering what your plans
> are for XML.  Is it going to be the same interface as
> your SQL databinding?

I'm not sure if you realise, but XML generation is already
implemented. It just isn't documented in the tutorial. Check
the JavaDocs for a quick summary.

Start out with SessionFactory.openDatabinder()

Basically, when I got round to implementing this, I
had a look around and discovered that the open source
solutions for databinding had improved a whole lot
and I didn't want to try and waste time doing what
other people are doing better. I figured plenty
of other projects are trying to let you arbitrarily
map XML to objects and vice-versa. So I decided
to do something real simple.

1. I didn't want to introduce yet another OO to XML
mapping language.
2. I wanted XML generation for persistent classes to
"just work". ie. you don't need to do any mapping
at all most of the time.
3. I wanted it to be _possible_ to customize the
generated XML either on a per-class or whole
application basis.

My solution was to use XSLT as the mapping language
and provide a default stylesheet that does what you
would probably want. You can customize the stylesheet
to alter the mapping for individual classes, or for
all classes at once. I kinda like this.

So XML generation became a two-step process.

1. generate a "generic" XML representation that is
amenable to manipulation by XSLT and includes as
much information as you could possibly want.

  <object class="Foo" package="cirrus.hibernate.test">
    <uid name="key" type
="string">52b16c9d:ecc0e74d:00ec:c0e7d476:0011</uid>
    <property name="foo" type="cirrus.hibernate.test.Foo" />
    .....
  </object>

2. use Xalan to process that XML with the (custom
or default) stylesheet.

  <Foo id="N400005">
    <key>52b16c9d:ecc0e74d:00ec:c0e7d476:0011</key>
    <foo/>
    ......
  </Foo>


There would be some extra problems in going backward
from XML to Java but I didn't want to waste too much
time on that problem if no-one was using hibernate for
XML generation. (I guess I should start by documenting
it, though.)

Re: [Hibernate-devel] SAP DB dialect

[Gavin_King/Cirrus%<CI...@ci...>]

> i have just commited the sap db dialect to cvs.

Excellent! Thanks Brad. :)

> gavin, r u still happy for me to change the default column name for the
> hilogenerator from next to next_hi (sap db gets upset when DBSchemaExport
> tries to create the hibernate_unique_key table with a column name of
next,
> as it is a reserved word)?

When we discussed this earlier other people seemed to prefer that we try
using quoted "next". If we can get that working with all platforms its
probably preferable. Can you try it out with SAP, please?

> the test suite fails on testCreateUpdate due to the size of the double in
> Foo.java.  sap db seems to support to +1e-64, but Foo's double is set to
> 1.33e-69, so the exponent seems to large to me.  however the jdbc driver
> appears to reduce it even more.  i could only get to 1.33e-36 for the
test
> to be successful.  i will send a message to the sapdb mailing list about
> this.

Interbase also has a problem like this, i think. I got round it by
disabling
part of the test. Thats a bit of a crude approach, I guess. Anyways, either
change or disable the test if you like, whatever works....

Have you got the schema export working? Someone else reported that the
"alter table add constraint" syntax is not supported by SAP DB so do
we need to support alternative forms in Dialect?

Does SAP support sequences or identity columns?