[Mark]

I first started with a Mac install of the all-in-one and it gave tons of errors going thru the tutorials.

Then I tried to use my PC instead, thinking it may be a Mac install issue.

I found the install was not working:

Ok, I abandoned Mac install and built up a brand new development machine with a blank PC machine.

It had the same problems.

Evidently the ALL-In-One install pulled in the latest GWT (2.1) code, which does not actually work with the scaffolding. The incubator file:

gwt-incubator-20100204-r1747.jar

has sections of code that are not ready for prime time / not working with core GWT library, so it causes it to fail.

Google released a fixed incubator file (built in November) which can be installed to fix this issue.

A discussion of the issue and fix can be found here:
http://code.google.com/p/google-web-toolkit-incubator/issues/detail?id=377

On to next issue, now that the new file has been included in the build path the jsp files are not compiling correctly.

I will post here the fix if I find it. Or Spring could pipe in with some help.

The JSP files are failing to compile still.

Mark

[Mark]

I rolled back to GWT 2.04, and still I am getting a ton of errors.

In reading through the posts here I get the feeling that this product is not at all stable.

I would love to use it, but I have wasted a week of my time trying to fix issues that a clean install should have taken care of.

Regretfullly,
Mark

[jkennedy]

Mark,
I’m sorry that you are having issues in this area and that we did not respond to your message sooner.

The 8.6 product supports GWT 2.0.x, we are working on GWT 2.1 support now.

Thanks for highlighting the updated GWT Incubator distribution, the GWT incubator dependency will be removed when we release our 2.1 support in favor of the UI updates that are part of GWT 2.1 core.

The Google Eclipse plugins that we depend on will include various versions of GWT and GAE depending on which version gets installed.
If you point the Google Tooling at your GWT 2.0.4 installation and scaffold a new project, the project should compile and run without issue.

If you run into problems with a cleanly generated project using this approach please post any errors that you encounter and we will take a look.

Our goal is obviously to save you time and I am disappointed that you were not able to find a path to utilize the tool without assistance.

The product is generally stable, and my assumption is that there is a minor step missing that was causing you problems.

You can also reach me directly at [email protected] and I will be happy to make sure you get up and running with minimal further investment.

Thanks,
Jack

[neyde]

More info can be found here:
https://www.genuitec.com/forums/topic/gwt-scaffolding-in-me4s-8-6-x-requires-gwt-sdk-2-0-4/

[Mark]

I started from fresh and documented every step, I will email to you Jack, and it gave some errors and warnings, but almost worked.

I added selecting Atomikos 3.6.4, as it had errored on that last time.

Here is the start of my log, if it helps anyone:

Install fresh 8.6.1 All in one install
Install Google plug-in for Eclipse with MyEclipse configuration center

Create project > Web Project
name= testGWT
Select Yes to Compiler Compliance dialog to use custom setting
Select Google>App Engine Settings…
Choose User Google Web Toolkit, specific SDK = 2.04
Choose Web Application, Project has WAR dir. = WebRoot
Choose App Engine, User Google App Engine = 1.4.0
OK to exit

Select MyEclipse > Scaffold CRUD App.
Choose Database Schema
Choose MyEclipse Derby
Choose CLASSICCARS
Choose CUSTOMER Add
NEXT
Base Package = com.Test
Select GWT, MVC WebFlow to generate
Next (did not allow Pickering selection due to more than GWT project selected)
On Run Dependencies, checked Atomikos 3.6.4 due to error on Atomikos last fresh build.
All defaults except as noted, Finish

[jkennedy]

Thanks again Mark,
I sent you a direct note but I am adding information here to help others who may encounter issues in this area.

We marked our support for GAE as experimental in this release mainly because we believe that many cases that would result from reverse engineering will not be supported by DataNucleus and GAE yet. When GAE for Business rolls out with SQL Service support most cases should be supported.

I would recommend that if you intend to deploy to GAE that you use a Google project rather than a Web Project.
The Google tooling and its approach to automatic classpath management can compete with the Web Tools classpath management and result in duplicate libs on the project which causes DataNucleus to stop enhancing your classes.

If you run through the same steps on a Google project, I believe you will be able to run the GWT compile, and run and deploy the project as a Web Application, etc.

If you run into an issue where DataNucleus says that your Entity has not been enhanced, you may be encountering a known issue with the google tooling described here: http://groups.google.com/group/google-appengine-java/browse_thread/thread/7ef71e1ed363e4a0.

If you look for the DataNucleus console it will tell you where to find the log and you can see if you are getting errors during the enhancement process. You may also need to go to the Google / App Engine / ORM settings and add explicit paths to your entities to get them to be seen.

As I noted above, the cases you can run through now are a little restrictive in the types of relationships that would be supported, types of primary keys that can be used etc. For example, running through scaffolding on the Customer table will result in an Entity with an Integer primary key but DataNucleus may require a Long and so you may need to change that manually.

Please let me know if using a Google project, with your Entities setup in the ORM options, and only one copy of the Data Nucleus libs on the classpath solves the issues you were seeing.

Thanks,
Jack

[Mark]

I went thru and tried starting with a Google project instead, and it had the exact same errors (good news to some extent)

I went and followed the App Engine Deep Dive exactly and it failed. It gave about 75 missing link errors, I think it may be a pathing issue, and it could be related to the newer version of the app engine api. augh.

I am currently doing round the clock development with my dev. team and may need to let scaffolding go.

Mark

[Mark]

I went thru and tried starting with a Google project instead, and it had the exact same errors (good news to some extent)

I went and followed the App Engine Deep Dive exactly and it failed. It gave about 75 missing link errors, I think it may be a pathing issue, and it could be related to the newer version of the app engine api. augh.

I am currently doing round the clock development with my dev. team and may need to let scaffolding go.

Mark

[Mark]

After 2 weeks of trying to resolve why the scaffolding is throwing errors while performing the same examples that are in the tutorials, I have decided this product is too buggy for my use right now.

Hopefully 9.0.1 release will work through these bugs.

Here are some tips for any struggling with the tutorials:

Download and use 2.0.4 of GWT
There is an updated incubator file that can be downloaded and used
Linkage Errors: At the final page of scaffolding wizard selecting to use all the libraries and copy them into your project will resolve some linkage errors.
The sample CLASSICCARS database uses Integer for primary key which is incompatible with GAE.
If you write some simple POJO (plain java) classes for the database (see deep dive with 2 parts), set all the fields as String instead of number will help it compile.
GAE does not like the DateTime object, there is a work around, but it still complains and doesn’t want to commit to database any table with it in it.

The tool does a ton of stuff, wish it was easier to get working.
Mark

[jkennedy]

Just to clarify,
Our support for GWT is for 2.0.4 and it will require that you install the GWT 2.0.4 SDK and point your Google plugins at that SDK.
Our support for GAE is marked as experimental until Google releases GAE for Business which will include full SQL support which may be needed depending on your data model or the data model that would be derived from your scaffolding inputs. For example, we do not automatically change the types of your primary keys to meet the requirements of data nucleus since we believe that may be unexpected to most developers.

We are actively working on supporting Googles technologies as they become available. I have posted work arounds to known issues in the Google tooling above regarding steps that may be needed to get your Entities to be found by DataNucleus.

Thanks,
Jack

[jkennedy]

Mark,
If you would like to send me your project I can try to determine why you may still be seeing issues.

Thanks,
Jack

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