ajrdatabase - Introduction

JAEOF: "Just Another EOF"

Feel free to help out! There's a long way to go...

This code is a fork of ajrdatabase written primarily by Alex J. Raftis
and published on SourceForge. The project there seems to be dead with no response from the current admin. Perhaps new life can be breathed into this project over here on github. An OpenSource implementation of Apple's Objective-C Enterprise Objects framework, arjdatabase is intended to be a plug-and-play replacement for Apple's EOF implementation. A strong attempt was made to make these frameworks adhere to the published EOF 4.5 API.

Currently there are database adaptors for OpenBase, Oracle, Postgres and SQLLite.

Status

Much of the low level EOSQLExpression code has been re-worked and very likely may have broken the existing adaptors for Postgress, OpenBase and SQLLite. These need to be tested to assure they still work.
An Oracle adaptor was added and it is fully tested and working.
Attribute binding is now working.
Changed joins to use newer Join syntax of "(Join semantic) table on atrrib1 = attrib2". This enables better database engine optimization and eliminates the need for complex code to place join clauses based upon qualifier semantics.
EOInterface compiles, but I have no idea what it's status is.
The EOModeler application code needs work, which is a shame as apparently a ton of work went into it. As of Jan 17th 2011 it compiles and runs. It is pre alpha at this point, but there is quite a bit that is working. I would love to get this working 100% again as anyone that wants to use this will need some sort of working EOModeler application. That said, the frameworks will work with any legacy EOModel file and most likely work with versions that are more current than 4.5.
Some optimization has been done here and there, but a lot more could be done. Because of the high level of abstraction that is going on, there are many issues with inefficiencies . These could be overcome somewhat by the use of caching and various other techniques.
To-many relationships now are snapshoted as they are supposed to be. Removing an object from a to-many EO relationship will result in that objects foriegn key being nulled or the object deleted as it should. Adding an object in a to-many does what it should even when there is no reverse relationships and all foreign key attributes are hidden.
As of 5/8/2012 I am considering this framework to be beta as it is passing all my tests. This is not to say it is free of bugs but at this point it needs real world testing to reveal problems.

Why?

Because, for me at least, I have over 100 very database intensive applications that are stuck in Tiger because they rely upon Apple EOF 4.5. Wouldn't it be great, if I could plug in a new framework that replaces EOF and they just need minor tweaks to get them working on the current Apple OS? Further, EOF is rather amazing in many ways and I know of nothing available that even comes close to the functionality that it provides. I realize there probably are very few people like me that need an EOF replacement, but EOF is extremely powerful and offers a high level of abstraction that makes creating applications that need to work with databases a snap.

Background

In 2000, WebObjects and EOF were state-of-the-art tools for building advanced web applications. Apple was in a state of flux, and had signed a pact with the devil to port WO/EOF to Java, and EOL the obj-c (& webscript) version of these great tools. For all of us that built enterprise software based upon the Objective-C version of EOF/WebObjects we had to port to Java or look for some other solution. Alex J. Raftis created the ajrdatabaes Open Source project around 2004 sometime and had many contributors to the project. I am uncertain how many people actually used the frameworks, but my impression is that it was used in production applications to some extent even though it was never truly christened as being anything but beta. It has gathered some dust as of late on SourceForge and the amin there seems to be absent. In September of 2011 I forked the SourceForge project so that I could contribute. This is a fork of that original project, but in no way does this represent a departure from the goal of the original project. This is meant to continue that project, just to do so in a new environment under active administration.

DISCLAIMER

There are many, many things that are only partially implemented, or not implemented at all. There are API elements that do not conform to the published API. The functionality of EOF is huge and much of this code has not been fully tested. My intent is to get this framework to a point where it can be used in a production environment. It is not ready for that at this point.

HELP

Any/all help would be greatly appreciated; If anyone out there is brave enough to give it a try, I'd be happy to help out. I would love constructive criticism and welcome any help that anyone would want to throw my way! It needs a lot of work; clean-up, optimization, I would love to see a MySQL adaptor, etc. etc.