[FIXED] How to programmatically call Eclipse format on a specific java file within a plugin handler?

Issue

I am wrting an Eclipse plugin that rewrites java files (possibly multiple files) based on the content of a selected java file (right click -> custom menu item).

Everything works as intended but the rewriting of the files doesn't manage the content formating so after using the plugin I have to manually format each affected java files with the Eclipse format action.

I am able to programmatically call the Eclipse format action on the selected java file but i'd like to also format all other files.

Here's what I have right now (the part that should change is within the for loop):

@Override
public Object execute(ExecutionEvent event) throws ExecutionException
{
    var workbench = PlatformUI.getWorkbench();
    var activeWorkbenchWindow = workbench.getActiveWorkbenchWindow();
    var selection = activeWorkbenchWindow.getActivePage().getSelection();

    List<String> generatedClasses = null;

    if ((selection instanceof IStructuredSelection structuredSelection)
            && (structuredSelection.getFirstElement() instanceof ICompilationUnit compilationUnit))
    {
        try
        {

            var projectClassLoader = getProjectClassLoader(compilationUnit.getJavaProject());
            generatedClasses = bindingGenerator.generateBindings(compilationUnit, projectClassLoader);
        }
        catch (ClassNotFoundException | NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException | IOException
                | IllegalClassFormatException | JavaModelException e)
        {
            // TODO pop an error message dialog?
            return null;
        }

        for (String generatedClass : generatedClasses)
            try
            {
                // I can find the IType of each affected java file here if it should help?
                var type = compilationUnit.getJavaProject().findType(generatedClass);

                // This is where the formating should be made. The code below currently format the selected file only.
                var commandId = IJavaEditorActionDefinitionIds.FORMAT;
                var handlerService = workbench.getService(IHandlerService.class);
                try
                {
                    handlerService.executeCommand(commandId, null);
                }
                catch (Exception e1)
                {
                    e1.printStackTrace();
                }
            }
            catch (JavaModelException e)
            {
                e.printStackTrace();
            }

    }

    MessageDialog.openInformation(activeWorkbenchWindow.getShell(), "Generated bindings on files:", String.join(", ", generatedClasses));

    return null;
}

Solution

Thanks to @greg-449 for pointing me out to ToolFactory.createCodeFormatter.

I just need to create a formatter with the project's options like this:

ToolFactory.createCodeFormatter(compilationUnit.getJavaProject().getOptions(true));

and then use the formatter on the file's sources.

Answered By - Fred
Answer Checked By - Timothy Miller (JavaFixing Admin)