A recap of Quarkus Tools for IntelliJ's latest improvements

Quarkus Tools for IntelliJ is a free and open source extension, helping users develop Quarkus applications by providing content-assist, validation, run configurations and many other features right from their favourite IDE.

This extension is based on the LSP4MP (i.e. MicroProfile) and its Quarkus add-on, and the Qute language server. These are all used in our popular Quarkus Tools extension for Visual Studio Code.

Over the past five months, we’ve been really hard at work to improve Quarkus Tools in every possible way, averaging about one release every two weeks.

We’ve been focusing on performance improvements, Quarkus 3.x with JakartaEE namespace support, Qute templating support, and generally trying to keep Quarkus Tools out of your way. So let’s look in more details at what was accomplished.

Increased stability and performance

We’ve addressed various critical issues in our custom Language Server client (LSP4IJ), that previously caused Language Servers to freeze IntelliJ IDEA. Improvements include:

  • Waiting until indexing is finished before launching the language servers.

  • Language server requests no longer blocking the editor.

  • Debouncing some requests to minimize heavy processing

  • New request cancellation support to avoid unnecessary processing.

  • Faster validation and lazy loading of quick fixes.

  • Reduced quarkus properties completion payload size.

  • Pre-emptively fetching Quarkus data in the Quarkus project wizard, in order to avoid waiting after clicking on the Next button.

These fixes contribute to a smoother coding experience, better overall performance, and, dare I say it, "developer joy".

Language Server client improvements

Language Servers console

Although not directly useful to users in most cases, the new Language Server console view is extremely important when we need to troubleshoot issues with the language servers.

The state of the servers is visible, stop and restart is available with a right-click, and you can enable different levels of tracing:

Language server configuration

The communication details between the IDE and the language servers are seen in the "LSP consoles" pane. In verbose mode, the messages can be expanded for more details:

Language server traces

This feature has proven invaluable in assisting us in diagnosing performance issues with the extension. It will enable users to provide valuable troubleshooting information in case any issues arise.

Language Servers preferences

A preference page is now available, under Preferences | Languages & Frameworks | Language Servers, allowing power users to configure language servers debugging and tracing: Language servers preferences

Application properties support

Completion improvements

Properties completion in application.properties files now displays icons and documentation (provided Preferences | Editor | General | Code Completion | Show the documentation popup is enabled): Quarkus properties completion

Completion is also available for enum values: Quarkus properties enum completion

Inlay hints

Properties using expression values are now resolved as inlay hints: Resolved property expression as inlay hint

Inlay hints can be disabled in Preferences | Languages & Frameworks | MicroProfile | Properties

Java editing improvements

New codelens for Vert.x reactive routes

Vert.x reactive routes now show a clickable codelens, that will open the browser to the configured URL, similar to JAX-RS endpoints:

Reactive routes

Qute improvements

We’ve spent significant effort on making the best Qute support around.

New syntax coloration

The Qute parser has been rewritten to allow for proper syntax coloration:

Qute Syntax coloration - light theme

Qute Syntax coloration - dark theme

Coloration settings are available at Preferences | Editor | Color Scheme | Qute.

Completion redux

Editing Qute templates is now better than ever, with new brackets autoclose, improved HTML integration, new completion icons. In particular, the enhanced snippet completion, that behaves like IntelliJ’s live templates, available for different Qute sections:

Qute snippet completion

Section {#} completion now displays user tags contributed by dependencies, like Renarde or Web Bundler: Renarde tags completion

Improved {#insert} and {#include} support

The {#insert} and {#include} sections can be used to specify the extended template to include in the current template. This release extends the support for these sections with validation, document link, completion, and code lens.

You can navigate by Ctrl+click (Cmd+click on Mac), from one template to another (referenced as user tags, via {#include} or {#insert}), or from a template definition from a java file to the actual file: Qute navigation

New template fragment support

Fragment sections define a part of the template that can be treated and rendered as a separate template. Support for fragments includes snippet completion, hover and validation. In a java class, you can navigate to a referenced #fragment via code lens and document link qute fragment support

Renarde support

Quarkus Tools now provides support for the Renarde web framework:

  • Public methods of sub-classes of a Renarde Controller automatically show a clickable codelens, even though they’re lacking a HTTP method annotation, as they’re treated as valid JAX-RS endpoints: Renarde endpoint codelens

  • Completion on the Renarde uri and uriabs namespaces lists available Renarde controllers: Renarde uri completion

  • Quick-fix is available to add missing input fields to a {#form} section: Renarde form quickfix

Type-Safe Message Bundles partial support

We have introduced partial support for Qute type-safe message bundles. If you defined @MessageBundle classes in your code, you’ll automatically get autocompletion for those messages in your Qute templates, with the messages rendered as inlay hints:

Message bundle support for Qute templates

Rendering messages from properties files is not yet supported.

Validation

Java files

Validation has been enhanced with the following features:

  • GraphQL void operations are now allowed in Quarkus 3.1 and higher and the correct placement of GraphQL directives is now checked: GraphQL directives placement validation

  • Quarkus BuildItem subclasses are checked whether they’re final or abstract: BuildItem validation

Severity mappings

We’ve tried to bind some Microprofile and Qute diagnostics reported by the language servers to IntelliJ’s Inspections settings, as it felt more natural than having specialized preference pages. But, since this is a bit of a hack, the inspections settings are mostly ignored, except for a couple severity settings. The limitations are described in each inspection description:

Inspection severity mapping

In most cases:

  • Scope: values are ignored

  • Severity: only Error and (Weak) Warning are respected. Other values mean no errors will be reported

  • Highlighting in Editor: values are ignored

Quick-fixes updating settings

We’ve introduced quick fixes that allow you to disable validation for certain errors. Useful, for instance, when you find false-positive errors add too much noise to your development workflow.

Unassigned @ConfigProperty properties (i.e not declared in application.properties) in java files, or unknown properties (seemingly unused) declared in application.properties can now be excluded from validation via a quick-fix, e.g:

Quick-fix to exclude property from validation

You can then update those exclusions in Preferences | Editor | Inspections | MicroProfile | Java files | Unassigned properties or Preferences | Editor | Inspections | MicroProfile | Properties files | Unassigned properties

Inspections settings

Similarly you can exclude a particular Qute template from validation, or its entire module

Exclude Qute template from validation

You can then head over to Preferences | Editor | Inspections | Qute | Templates | Validation,

Qute validation settings

Miscellaneous improvements

  • The Quarkus project wizard, on top of being super snappy, now offers easy (de)selection of extensions by double-clicking on them.

  • Projects in WSL2 are now supported.

  • Run configurations have been renamed to Quarkus Dev Mode, to minimize confusion with IntelliJ Ultimate’s built-in Quarkus support.

  • Vert.x reactive routes, JAX-RS and Renarde endpoints are now shown as implicitly used, as well as Quarkus @BuildStep-annotated classes and @Observer-annotated methods.

Looking forward

Quarkus' "developer joy" mantra obviously applies to your time spent in the IDE and that’s what the Red Hat Developer team is vying for. As we reflect on the past five months of releases, we’re pretty excited about the progress we’ve made on the Quarkus development experience, in IntelliJ IDEA.

And we’re not going to stop here, so stay tuned for more performance improvements and exciting new features in the coming weeks. We’re actually planning to make it easier for you to get those new bits as soon as possible, by publishing updates to the EAP release channel.

Finally, if you haven’t done it already, please add your review to the JetBrains marketplace. Your feedback matters!

In case you find bugs or have ideas for some great new features, don’t hesitate to head over to our Github repository and open a ticket.