Robert,
These are the *kind* of comments I am looking for; thanks for the
details, I have a few followup questions.
I also found that Cayenne is a cogent framework that results in
higher productivity because not only is it feature rich, but the work-
flow aspect is considered essential to the design (and not just an
afterthought). BTW, I also experienced the "quick-start" phenomenon
with Cayenne; it was a welcome surprise.
So after re-reading your comments, I suspect one of the more
important aspects is work-flow. In your experience, is it possible
to configure a number of 3rd party software to create the Cayenne-
like work-flow that is facilitated by CayenneModeler?
So unless one is a cowboy-programmer (ref Agile-insult :) ), then
evolving a database in a methodical manner would seem to be better
managed via the CayenneModeler and the Cayenne way of "groking"?
Joe
On Aug 9, 2007, at 4:28 PM, Robert Zeigler wrote:
In terms of raw mapping capabilities ("what can be mapped, and
how"), hibernate basically has cayenne beat at this point.
For example, hibernate supports things lie mapping to-many
relationships as lists, arrays, or maps ( cayenne currently only
supports mapping them as lists).
Cayenne may have some mapping facilities not in hibernate, but none
that I'm aware of offhand (maybe the extended types facility? Not
sure if hibernate has an equivalent to that,
but they probably do; oh, when I first starting using cayenne,
cayenne supported "lazy" relationship fetching and hibernate did
not, but hibernate now supports it).
As you mentioned, cayenne has the modeler, whereas hibernate does
not offer any such support (except through 3rd parties). ANd that,
in my mind, is the biggest difference. Not the modeler,
but the mindset. Hibernate is about "let's make an ORM with lots
of features". Cayenne is about "let's make a tool and library that
makes developers productive".
When I first delved into the world of ORM, I spent three days
trying to grok hibernate. Finally, recalling that some other users
of tapestry were using cayenne, I tried it.
Two hours later, my objects were mapped and created, my schema was
created, and I was writing my objects. I've never looked back. I
wish I could say that dichotomy has lessened;
that the hibernate people had realized "hey, people might actually
want to /use/ our project, instead of admire our technical genius
from a distance", but it doesn't appear that that's the case.
On their website, they have a "roadmap to getting started quickly
with hibernate". Here's their roadmap:
"Day 1: Work with the tutorials
* Download Hibernate 3.2 and extract the archive.
* Reference documentation: Read the tutorial, work with the
source code in the /doc/tutorial/ directory of the Hibernate
package. This tutorial covers a simple Hibernate standalone and web
application.
* Java Persistence with Hibernate: Read the tutorial in the
free sample chapter 2 of the book, download the Hello World code.
This tutorial is a complete introduction to Hibernate, Java
Persistence, and EJB 3.0.
Day 2: Read the Documentation
* Read the rest of the reference documentation.
* Consider reading the rest of the book Java Persistence with
Hibernate.
* Read the FAQ.
Day 3: Start Coding!
* Many examples you find on the Net are still Hibernate 1.x or
2.x - read the migration guide for a list of differences to
Hibernate3.
* Many good patterns can be found on the Wiki Community Area,
such as Sessions and transactions, Open Session in View, Generic
Data Access Objects, ...
* Once you are familiar with basic Hibernate, download the
CaveatEmptor example application."
(from: http://www.hibernate.org/152.html)
That's their "getting started quickly"... any questions? ;)
(I could also point out things like: why is the web page named
152.html? Is that: 152 hours of frustration before starting
hibernate? Is that 152 days of reading before you start? 152 things
you have to do before you understand hibernate? Granted, the name
of a web page has nothing to do with the technical quality of the
hibernate code. The technical quality of the hibernate code is,
I'm sure, very good. But it harks back to my original point of the
paradigm of the two projects. 152.html is not a name that you could
guess as a user. Similarly, the hibernate "way" is nothing
something you can guess your way through and be pleasantly rewarded
when something that you tried thinking "I wonder if this will work"
actually does.
Now compare that to cayenne's quick start for cayenne version 2.0.
http://cayenne.apache.org/doc20/quick-start.html
Hey, look, I know what that url is telling me... and I generally
know what the cayenne API is telling me and asking me, even before
reading the javadocs...
without reading other tutorials...
For me, that's one of the key differences, and one of the main
things that keeps in using cayenne. Keep in mind, this is all user
perspective. I'm sure there are people out there who find hibernate
easy to use... erm, maybe?
Robert
PS: cayenne also has ROP, which hibernate doesn't, so if you
interested in writing swing front ends (truly "rich" client apps,
instead of lame webapps... oops, did I say that? ;), cayenne is a
no-brainer...
PPS:
On Aug 9, 2007, at 8/91:23 PM , Joe Baldwin wrote:
This is a general question I would guess at the "use case" level.
I was recently in a conversation in which I was challenged about
the selection of Cayenne over Hibernate. I have only researched
Hibernate & run some elementary demo tests. My conclusion was
that Hibernate allows you to create a mapping via an XML metadata
file but that some of the mapping responsibilities (currently
found in Cayenne) are left to the programmer to resolve and
maintain. I specifically pointed to Cayenne Modeler as an example
of an essential tool supporting the 'change it in one place'
philosophy that impacts maintenance time budgeting.
It was asserted that Hibernate could do anything that Cayenne
could do. In addition, the CayenneModeler advantage was dismissed
with a comment concerning an Eclipse plugin that is supposed to
support the same features.
Things change very quickly in the OpenSource world so perhaps I
could have made a mistake, however, I don't think that I am that
far off the mark. Is there a white paper that might discuss the
differences (couldn't find one at the Hibernate site)? Does
anyone have an opinion?
