Investigation results regarding Xcore support (plantuml/issues/112)

[OepenerPlatt]

Details of the issue can be found here : hallvard#112 (comment)

[OepenerPlatt]

Goods news : I managed to reactivate the support for xcore files that was initially developed by Hallvard Trætteberg.
The issues encountered and the fixes need further discussion/rework in order to be contributed back to the original repo.

Small issues

• Project 'net.sourceforge.plantuml.lib' is missing required library: '\Users\travkin\Documents\git-repos\plantuml4eclipse\bundles\net.sourceforge.plantuml.lib\lib\plantuml-epl-1.2023.11.jar' #1

Target Platform changes

• Neither an available bundle nor the associated JRE export package 'org.eclipse.xtext.resource' #2
• Xcore is missing when testing IDE #7

IDE setup and launch

• I'm on Windows ? IDE does not start - Caused by: java.lang.NoClassDefFoundError: org.eclipse.swt.SWTError #5
• PlantUML4e-2022-09 : JVMJ9VM007E Command-line option unrecognised: -XstartOnFirstThread SAME FOR -Xdock:icon=../Resources/Eclipse.icns #6

To be discussed

• I commented the code, need some examples/help org.eclipse.uml2 cannot be resolved to a type #4
• could be loaded from maven central in the targetPlatform The import net.sourceforge.plantuml.FileFormat cannot be resolved #3

To be further investigated

• xcore intent provider does not get activated #8
• Xcore : supportsSelection ?? #9
• java.lang.NoClassDefFoundError: org/eclipse/xtext/ui/editor/model/IXtextDocument at net.sourceforge.plantuml.xcore.XcoreDiagramIntentProvider.getDiagramInfos #10

[travkin79]

Hi @OepenerPlatt,
I checked your ecore_support branch. It turns out, it's difficult to see what you changed when comparing to the original repo's master branch. Shouldn't there be only a few modified / added classes? Shouldn't the plug-ins go to the bundles folder? It seems, you re-used some of Hallvard's commits, did you?

[OepenerPlatt]

Hi @travkin79,
yes, you're right. Work is not finished yet.
I encountered a couple of difficulties while setting up the ide to solve the original issue.
I wanted to document them in order to be able to discuss them with you and see how they could be solved.
Take issue #1 as an example : This seems to be a small error in the classpath contained in the repo.
What should I do with that ? Open an issue on the plantuml project and solve it ?
Could you take a look into the other issues too ?
I would like to propose a couple of commits according to your suggestions.
And then finally gather the code that solves the original issue (xcore not being supported anymore).
I indeed reactivated the code that was removed 10 or so years ago by reapplying a couple of Hallvard's commits with some minor changes.
I would like to bundled this into a commit to be contributed back to the original repo.
Please let me know how we could go further.
Many thanks in advance.

[travkin79]

Hi @OepenerPlatt,
Thanks for clarification. I think, I can help you with the issue, but it may take some time (due to my resource limitations).

Issue #1: That's my fault. Usually, I try to avoid user-specific paths in config files. Nevertheless, I'm working on simplifying plantuml library updates and will fix the classpath here anyway. I'll use a relative path here instead. The change will soon be committed / merged to the develop branch in the original repo. You could then merge the changes to your fork. There's no need to open an extra issue for that.

Step by step, I'll take a look at the other issues, too. Do you want me to create pull requests on your fork? This way, we both could make changes to the code. In addition, we could keep using this discussion.

[OepenerPlatt]

Hello @travkin79,
no problem, I have time ...
I would like to review the issues myself first and propose the fixes accordingly.
Give me some time to do that.
We could then work together on my fork if you want and see what is meaningful to be contributed back to the original repo.

[travkin79]

Some other hints:

• I saw, you're using the class net.sourceforge.plantuml.xcore.XcoreDiagramTextProvider in the net.sourceforge.plantuml.xcore/plugin.xml. DiagramTextProviders seem to be deprecated. The latest PlantUML plug-ins use DiagramIntentProviders, sub-classes of net.sourceforge.plantuml.text.AbstractDiagramIntentProvider. The extension you're using here might be obsolete.
• It seems you also re-created the obsolete XcoreDiagramTextProvider classes. I think, you should try to get the XcoreDiagramIntentProvider running instead, maybe by using the diagramIntentProvider extension point instead of the diagramTextProvider extension point. I tried that and at least the text provider preference gets activated for xcore.

• Could you please rebase your changes on the latest master branch from original git repository as soon as you're finished, so that I can better see what changed? Currently, your branch seems to contain a lot of obsolete code, e.g. multiple plug-ins in the root folder. The laster implementation in the original repo has all plug-ins in the bundles sub-folder.
• Your build.cmd has user-specific paths and wouldn't work on other machines. You could create a launch config for Maven / m2e instead using variables.

[pbrossel]

Many thanks for your support and the time spent! It has helped me a lot.

I would like to go on further in this way :

• rebase on your latest changes in the main repo.
• restart the setup from scratch and document the steps. Could be useful for others that want to contribute.
• finalize work on the initial issue.

• I saw, you're using the class net.sourceforge.plantuml.xcore.XcoreDiagramTextProvider in the net.sourceforge.plantuml.xcore/plugin.xml. DiagramTextProviders seem to be deprecated. The latest PlantUML plug-ins use DiagramIntentProviders, sub-classes of net.sourceforge.plantuml.text.AbstractDiagramIntentProvider. The extension you're using here might be obsolete.
• It seems you also re-created the obsolete XcoreDiagramTextProvider classes. I think, you should try to get the XcoreDiagramIntentProvider running instead, maybe by using the diagramIntentProvider extension point instead of the diagramTextProvider extension point. I tried that and at least the text provider preference gets activated for xcore.

Yes, you're right. I indeed wondered why a change fromTextProvider to IntentProvider was made more or less 10 years ago.
The deprecated version builds the plantuml source as I would like to see it, while the new version show something the EMF internals instead.
I have the impression that the migration was abandoned in these days for some reason.

• Your build.cmd has user-specific paths and wouldn't work on other machines. You could create a launch config for Maven / m2e instead using variables.

I used this to launch the build easily. Should have better been placed outside the repo to keep things clean.
A launch config is a far better idea. I'll try it out asap.

[pbrossel]

I just noticed that I was commenting under my other github user.
The physical person behind @OepenerPlatt and @pbrossel is in fact the same.
I set up @pbrossel to match my eclipse account that is required to be the same when contributing to the xtext/xtend project.
Your comment hallvard#178 (reply in thread) urged me to try to help a little bit in this famous project : eclipse/xtext#2337 (comment).

[travkin79]

I just noticed that I was commenting under my other github user.
The physical person behind @OepenerPlatt and @pbrossel is in fact the same.

That's what I guessed. :-)

Your comment hallvard#178 (reply in thread) urged me to try to help a little bit in this famous project : eclipse/xtext#2337 (comment).

Good to hear that you want to help keeping the xtext project and sub-projects alive. 👍