Unable to use the Java source file corresponding to the class file as context

[chenweiye120]

Hello, the platform is: Eclipse 4.39 + Copilot 0.16.0.

When importing a plugin project, if the imported project only contains JAR files and does not include source code, Eclipse can open the class file and display the source files associated with that JAR. However, in Copilot, the source file corresponding to that class file cannot be selected as the AI's context. If Copilot is prompted at this point, it will search for the Java file, but the Java file is not in the project. The output will be:
...
Searched for files matching query: org.eclipse.core.resources/*/.java
Read directory org.eclipse.core.resources
...
In other words, the corresponding Java file cannot be found for analysis. Therefore, the AI ​​cannot read the Java file corresponding to the class file and cannot use it as context for analysis.

[iloveeclipse]

This is known limitation (even two of them):

1. ClassFileEditor doesn't use BufferManager to manage its document
2. ClassFileEditor doesn't work on IFile either but uses externally saved (extracted) content, see org.eclipse.jdt.internal.ui.javaeditor.InternalClassFileEditorInput.getPath()

We might have a solution here, but this would require changes in JDT.

• First: we would need to create the file not somewhere on the disc but in an "invisible" project, so that the file will be "real" IFile.
• After that, wither we use BufferManager to manage this file
• Or we provide document adapter to IFile, similar to the recent fix for Xtext editors support in LSP4E (see Adapt document to IFile when unable to retrieve file from buffer manager eclipse-lsp4e/lsp4e#1501 & add IAdaptable support to IXtextDocument interface eclipse-xtext/xtext#3615).

[jdneo]

Another idea it register the jdt uri schema as a content provider to the CLS. If cls meets such uri, delegate the read action to the IDE side.

We already did this for the ABAP support.