Re: Design Advice - Relational Databases & Java Objects

Subject: Re: Design Advice - Relational Databases & Java Objects From: Jeff Duska <[EMAIL PROTECTED]> === I think this is the point that Vic was making. The transaction that you will thinking of in the application might not nicely map to simple DAO objects. While I might have Order

Re: Design Advice - Relational Databases & Java Objects

ginal Message - From: "Adam Hardy" <[EMAIL PROTECTED]> To: "Struts Users Mailing List" <[EMAIL PROTECTED]> Sent: Wednesday, June 05, 2002 4:19 PM Subject: Re: Design Advice - Relational Databases & Java Objects > ... (still being dim) ... but how do the DAOs

Re: Design Advice - Relational Databases & Java Objects

> > >>>Transaction makes the same Connection available > to all > >>>DAOs in the same thread by storing it in a > ThreadLocal > >>>variable, so I don't have to pass the transaction > around. > >>> > >>>robert > &

Re: Design Advice - Relational Databases & Java Objects

t; > >>-Original Message- >>From: Adam Hardy [mailto:[EMAIL PROTECTED]] >>Sent: Wednesday, June 05, 2002 2:33 AM >>To: Struts Users Mailing List >>Subject: Re: Design Advice - Relational Databases & Java Objects >> >> >>Aha, ThreadLocal

RE: Design Advice - Relational Databases & Java Objects

st > Subject: Re: Design Advice - Relational Databases & Java Objects > > > Aha, ThreadLocal. Sounds good, but I still have problems working out how > the DAOs get there. OK, I'm possibly being a bit dim here - how does the > DAO access the ThreadLocal holding y

Re: Design Advice - Relational Databases & Java Objects

To: Struts Users Mailing List >>Subject: Re: Design Advice - Relational Databases & Java Objects >> >> >>Hi Robert, >>that is more or less what I am aiming to do. I see you don't pass >>connections around - at least not across your business to DAO interface. >&g

RE: Design Advice - Relational Databases & Java Objects

2 4:46 PM > To: Struts Users Mailing List > Subject: Re: Design Advice - Relational Databases & Java Objects > > > Hi Robert, > that is more or less what I am aiming to do. I see you don't pass > connections around - at least not across your business to DAO interfac

Re: Design Advice - Relational Databases & Java Objects

Hi Robert, that is more or less what I am aiming to do. I see you don't pass connections around - at least not across your business to DAO interface. So from your code snippet, I guess your transaction object gets the connection and puts it somewhere that the DAOs can find it? Or do you pass y

Re: Design Advice - Relational Databases & Java Objects

> If the data access objects completely encapsulate > the connection stuff, > how does the business object wrap two calls to the > data access layer in > one transaction? Take for example the well-worn > credit and debit > financial transaction. Would you wrap that up into > one data access > obj

Re: Design Advice - Relational Databases & Java Objects

> >> >>As mentioned elsewhere, getting a database connection from the web tier >>is not a good practice. The Struts framework does try to encourage best >>practice but sometimes takes a dip in the pool of pragmatism. The >>Generic Connection pool is one example of this. The data access objects

Re: Design Advice - Relational Databases & Java Objects

> > >As mentioned elsewhere, getting a database connection from the web tier >is not a good practice. The Struts framework does try to encourage best >practice but sometimes takes a dip in the pool of pragmatism. The >Generic Connection pool is one example of this. The data access objects >should

Re: Design Advice - Relational Databases & Java Objects

> (1) Is it best for the data access layer to throw exceptions on error to > be picked up by the business objects & then struts actions, or would it > be good to use a struts-type message object and use strings in the > application resources file (I'm just worried my exceptions' text would > not b

Re: Design Advice - Relational Databases & Java Objects

Subject: Re: Design Advice - Relational Databases & Java Objects From: Vic C <[EMAIL PROTECTED]> === Somone someplace need to know "how" the DB layer talks to DB. No magic in computers, and a common applied practice is roll your own beans. The beans need to logicaly map

Re: Design Advice - Relational Databases & Java Objects

[EMAIL PROTECTED]> Sent: Friday, May 31, 2002 10:01 AM Subject: Re: Design Advice - Relational Databases & Java Objects | There's still one question I've got about using object - relational | mapping & DB access packages: | | what happens when I want to pull out a COUNT(*) on a g

Re: Design Advice - Relational Databases & Java Objects

ng a class to expose your >>>collections of value objects to the view layer >>> >>>All of these things are done for you. >>> >>>Plus, it works with any SQL database, not only Oracle. :-) >>> >>>I'm planning a whitepaper that spec

Re: Design Advice - Relational Databases & Java Objects

> >__ > >Steve Muench - Developer, Product Mgr, Java/XML Evangelist, Author > >Simplify J2EE and EJB Development with BC4J > >http://otn.oracle.com/products/jdev/htdocs/j2ee_bc4j.html > >Building Oracle XM

Re: Design Advice - Relational Databases & Java Objects

Product Mgr, Java/XML Evangelist, Author >Simplify J2EE and EJB Development with BC4J >http://otn.oracle.com/products/jdev/htdocs/j2ee_bc4j.html >Building Oracle XML Apps, www.oreilly.com/catalog/orxmlapp >- Original Message - >From: <[EMAIL PROTECTED]> >To: "St

Re: Design Advice - Relational Databases & Java Objects

ichael Mok www.teatimej.com - Original Message - From: "Adam Hardy" <[EMAIL PROTECTED]> To: "Struts Users Mailing List" <[EMAIL PROTECTED]> Sent: Thursday, May 30, 2002 7:06 PM Subject: Re: Design Advice - Relational Databases & Java Objects > Michael, >

Re: Design Advice - Relational Databases & Java Objects

essage - From: <[EMAIL PROTECTED]> To: "Struts Users Mailing List" <[EMAIL PROTECTED]> Sent: Wednesday, May 29, 2002 6:44 PM Subject: Re: Design Advice - Relational Databases & Java Objects | | | | Adam - | | Have you looked at Torque from the Jakarta Tubine project? |

Re: Design Advice - Relational Databases & Java Objects

h you define how you want >> Castor to connect to the database (eg JDBC driver or JNDI or connection >> pool) >> >> I am not selling Castor, but just like to share my experience. >> >> Michael >> >> >> >> -Original Message- >> Fro

Re: Design Advice - Relational Databases & Java Objects

pool) > >I am not selling Castor, but just like to share my experience. > >Michael > > > >-Original Message- >From: Adam Hardy [mailto:[EMAIL PROTECTED]] >Sent: Thursday, 30 May 2002 17:33 >To: Struts Users Mailing List >Subject: Re: Design Advice - Rela

RE: Design Advice - Relational Databases & Java Objects

like to share my experience. Michael -Original Message- From: Adam Hardy [mailto:[EMAIL PROTECTED]] Sent: Thursday, 30 May 2002 17:33 To: Struts Users Mailing List Subject: Re: Design Advice - Relational Databases & Java Objects Hello Jerome, I'm not sure why I'm so bad at

Re: Design Advice - Relational Databases & Java Objects

Hello Jerome, I'm not sure why I'm so bad at searching the net & not finding things like this. ObjectBridge has a feature list that blows me away. Are you using it? Castor also looks interesting. Why do you refer me to JBoss & openEJB? I've no experience with EJB, but from what I know, I presu

Re: Design Advice - Relational Databases & Java Objects

Hi Kevin, from what I can glean from their website, torque implements what Martin Fowler calls the Gateway pattern - tables are directly related to classes - but I need his DataMapper pattern (where a finder object finds the data and a mapper turns it into anything you like). Adam [EMAIL PROT

RE: Design Advice - Relational Databases & Java Objects

Have you looked at these opensource projects? JBoss http://www.jboss.org/ OpenEJB http://www.openejb.org/ Castor JDO http://castor.exolab.org/ ObjectRelationalBridge http://objectbridge.sourceforge.net/ As for (1) I would have the business objects throw exceptions. I would have the Struts Actio

Re: Design Advice - Relational Databases & Java Objects

Adam - Have you looked at Torque from the Jakarta Tubine project? I haven't used it but have heard good things about it. It provides an ability to perform O/R mapping using an XML configuration file - and (as I understand) it creates Java files for you that implement a peristence layer. FWIW

Re: Design Advice - Relational Databases & Java Objects

IMHO It's better that any db access layer does not know "how" to get a database connection, it just gets given them by the client calling it. This way if you need to change the way you grab db connections the db access layer is none the wiser and no code changes are needed Jin - Original Me

RE: Design Advice - Relational Databases & Java Objects.

info on the commercial stuff: http://www.object-relational.com/object-relational.html -Original Message- From: Francisco Hernandez [mailto:[EMAIL PROTECTED]] Sent: Wednesday, April 17, 2002 11:38 AM To: Struts Users Mailing List Subject: Re: Design Advice - Relational Databases & Java

Re: Design Advice - Relational Databases & Java Objects.

ril 17, 2002 4:41 AM Subject: RE: Design Advice - Relational Databases & Java Objects. > Rob, > > Sun's blue prints are an excellent resource to get an idea of how to handle > data access via the web tier. > In general, I use the Struts action classes as proxies to my business &g

RE: Design Advice - Relational Databases & Java Objects.

For a O-R mapping patterns solution that is integrated with Struts, have a look at the open source Expresso Framework at www.jcorporate.com. -- To unsubscribe, e-mail: For additional commands, e-mail:

RE: Design Advice - Relational Databases & Java Objects.

[EMAIL PROTECTED] cc: Subject: RE: Design Advice - Relational Databases & Java Objects. I'm sure you've got many useful replies already, but let me add my two cents: I'm using Torque as an Object-Relational persistence mechanism, and am getting a lot of mileage out of

RE: Design Advice - Relational Databases & Java Objects.

I'm sure you've got many useful replies already, but let me add my two cents: I'm using Torque as an Object-Relational persistence mechanism, and am getting a lot of mileage out of it. It's *part* of the Jakarta Turbine project, is easy to use, and works well. Among other things, it generates a