1. The Eclipse integration works great. If a developer chooses, they can stay entirely within the Eclipse universe. This has been very important for continued development on Windows boxes. The WOLips team has created a replacement for all the functionality that WO developers get with Xcode and the other Apple WO tools, but with the additional features of a pure Java IDE (such as code refactoring). In my opinion the only drawback to going completely the Eclipse route is the loss of a tool called WOBuilder that allows graphical creation of application interfaces. In Eclipse (for the moment, anyway) you must create the bindings in a text interface. Many developers would say that the near instantaneous code completion in Eclipse actually allows a faster workflow. Fortunately you can use whatever combination of Eclipse and Apple tools that suit your fancy at the moment.
2. The major open source frameworks are called Project WOnder. It extends the WebObjects frameworks. It also counts among its code contributors people that now work at Apple (I don't know if they continue to contribute or not). There are several other open source frameworks available created by different individuals and organizations.
3. Apple has deprecated the Cocoa(objective-C) - Java bridge. Several of Apple's WO specific tools (EOModeler, WOBuilder) depend directly on that bridge being present. It is not clear when the bridge itself is going to disappear. For the moment it is present. This is why there has been a push to open source Java programming tools. Here is the Apple announcement: http://lists.apple.com/archives/webobjects-dev/2006/Aug/msg01144.html
4. WebObjects applications can be freely deployed on any platform. The licence does not tie it to Apple hardware. On the other hand, the development licence IS currently tied to Apple hardware, I think.
5. WebObjects has not gone back to ObjC. That died with version 4.5.1. It has been completely ported to Java since about 2001.
6. WO is still exciting but has a wicked learning curve (WO Developers call it the learning cliff - the upside is that you learn a lot in a short period of time ;-). There are really smart programmers in the developer community most of which are content to continue to use WO as the secret weapon in their web development arsenal. Many migrate to other solutions for given projects and then come back and say how inferior their experience was.
7. I personally have used other stuff such as PHP/MySQL and there is really no comparison with WO if you have a database backend. Moving from the scripting languages to object oriented technologies like .Net/RoR must have come closer, but I have never dealt with those frameworks.
Here's a great WO resource if you want to have a closer look:
I notice whenever I click an iTS URL or visit the Apple Store that Apple is using its tech, which I imagine means it gets adequate love from developers who are keeping it up to date because they need it to work every day. I see it as good for the technology. I just have little idea how widespread its non-Apple use is.
AAA also uses a ton of WebObjects.
I looked at http://www.aaa.org ... I'm thinking I'm on the wrong wavelength here ....
The fact that Eclipse is a multi-platform tool seems to make it an interesting choice. I suppose now that WO isn't ObjC, it can be deployed from more platforms? What are the limits? Is it not really a tool for causing Apple sales?
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