Question

So, I’m looking to develop a plugin for Eclipse 4.2 that monitors edits that a user makes to their files.

This is my first Eclipse plugin, and to prepare, I walked through the Eclipse plugin development cheat sheet (HelloWorld) and spent many hours on help.eclipse.org looking through the documentation and the API. I think I have some idea of what tools I need, but I’m not sure how to put those tools together to do what I want.

Desired Results: Have a plugin that’s kept apprised of every new letter added to a (Java) editor and any and all deletes. This includes things that Eclipse does (auto-completing variables, curly braces) as well as what the user types.

Tools that might help: I’m thinking that a IResourceChangeListener will assist, as it gives me a IResourceChangeEvent, with an accessible IResourceDelta which represents workspace changes. Also, since editors extend EditorPart, I’m thinking that adding a IPropertyChangeListener to the relevant editor may be useful as well.

I think I’ve got the right tools, but I’ve got no idea how to go about assembling them to do as I wish.

Questions:
Are the tools listed above the proper ones for the job?
How can I get a list of all editors opened or that will be opened and add listeners to them?
Any additional tips for resources on learning how to program Eclipse plugins?

Answer 1

Krumelur’s tip gave me a good starting point. The DocumentEvents returned by IDocumentListener are granular enough to give me a character by character analysis of what happened.

IEditorPart editor = ...;  
IEditorInput input = editor.getEditorInput();  
IDocument document=(((ITextEditor)editor).getDocumentProvider()).getDocument();

document.addDocumentListener(new IDocumentListener() {

        @Override
        public void documentChanged(DocumentEvent event) 
        {
            System.out.println("Change happened: " + event.toString());
        }

        @Override
        public void documentAboutToBeChanged(DocumentEvent event) {
            System.out.println("I predict that the following change will occur: "+event.toString());


        }
    };
});

As far as what I should extend, I extended org.eclipse.ui.startup and added a series of listeners until I got to the code that looks like what I’ve got above.

I hope this helps anybody else who is looking for what I was.