Java Extension for Nova

A comprehensive Java development extension for Nova editor, providing rich language support through Eclipse JDT Language Server, tree-sitter syntax highlighting, and integrated linting.

✨ Features

• Syntax Highlighting - Fast, accurate syntax highlighting via tree-sitter
• Code Intelligence - Powered by Eclipse JDT Language Server
• Auto-completion
• Hover documentation
• Signature help
• Navigation
• Jump to Definition
• Jump to Type Definition
• Jump to Implementation
• Find References
• Find Symbol
• Code Actions
• Format File
• Organize Imports
• Rename Symbol
• Linting - Real-time diagnostics and error checking
• Code Folding - Fold classes, methods, blocks, and comments
• Symbol Outline - Navigate your code structure

Java Development Kit (JDK)

You need JDK 21 or later installed on your system.

macOS:

# Check if Java is installed
java -version

# Install via Homebrew
brew install openjdk@21

Eclipse JDT Language Server

The extension requires Eclipse JDT.LS (Java Language Server).

Installation via Homebrew (Recommended):

brew install jdtls

🚀 Getting Started

1. Install the Extension
2. Open Nova
3. Go to Extensions Library
4. Search for "Java"

5. Click Install

6. Configure JDK Path (if not auto-detected)

7. Open Extension Preferences: Extensions → Extension Library → Java → Preferences
8. Set "Java JDK Home" to your JDK installation path

9. Example: /Library/Java/JavaVirtualMachines/jdk-21.jdk/Contents/Home

10. Open a Java Project

11. The extension activates automatically when you open .java files
12. Supports Maven (pom.xml) and Gradle (build.gradle) projects
13. For Eclipse projects, ensure .project file exists

⚙️ Configuration

Global Settings

Access via Extensions → Extension Library → Java → Preferences

Language Server:
- Choose between automatic or custom language server
- Configure custom JDK path
- Set language server path

Formatting:
- Enable/disable format on save
- Choose formatter: Language Server (Eclipse JDT) or Gradle Spotless
- Choose formatting style (Google, AOSP, Eclipse, Palantir, or Custom)

Linting:
- Enable/disable diagnostic linting

Workspace Settings

Access via Project → Project Settings → Java

Configure per-project settings:
- JDK home
- Format on save behaviour
- Formatter choice (inherit from global or override)
- Source paths
- Output path
- Referenced libraries (JAR files)

🎨 Formatting

The extension supports two formatting approaches:

Language Server Formatter (Eclipse JDT)

Uses the built-in Eclipse JDT formatter with these style presets:

• Google Java Style - Google's Java style guide
• AOSP - Android Open Source Project style
• Eclipse - Eclipse IDE default style
• Palantir Java Format - Palantir's Java style
• Custom - Configure your own style

Gradle Spotless Formatter

Uses Gradle Spotless with Palantir Java Format. This option:

• Runs ./gradlew spotlessApply on format
• Requires a Gradle project with Spotless configured
• Uses your project's existing Spotless configuration
• Modifies files on disk (you'll need to reload after formatting)

To use Spotless:
1. Ensure your project has build.gradle with Spotless configured
2. Set formatter to "Gradle Spotless (Palantir)" in preferences
3. Format will run ./gradlew spotlessApply automatically

Example Spotless configuration in build.gradle:

plugins {
    id 'com.diffplug.spotless' version '6.x.x'
}

spotless {
    java {
        palantirJavaFormat()
    }
}

🔧 Commands

All commands are available in the Editor menu when editing Java files:

• Jump To Definition - Navigate to symbol definition
• Jump To Type Definition - Navigate to type definition
• Jump To Implementation - Navigate to implementation
• Find References - Find all references to a symbol
• Find Symbol - Search for symbols in workspace
• Format File - Format current file (⌥⇧F)
• Organize Imports - Organize and optimize imports
• Rename Symbol - Rename symbol across workspace
• Restart Language Server - Restart the Java language server

Acknowledgements

• This repo is heavily inspired (originally forked from) the nova-gobee extension.

Enjoy coding in Java with Nova! ☕️

v 1.0.2
- Fixed issues with LSP not always activating
- Published repository to github
- Updated readme

v 1.0
- Initial version

MIT License

Copyright (c) 2024 Nova Java Extension

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.