vscode-javals

This is a VS Code extension to launch the JavaLS language server.

Prerequisites

• Node.js 18+ and npm
• Java 17+ (JAVA_HOME or java on PATH)
• Sibling java-ls Maven project (for local/dev server builds)

Expected layout:

<parent>/
  vscode-javals/    ← this extension
  java-ls/
    java-ls/
      target/java-ls.jar

Build

1. Install extension dependencies:

   npm ci
   

2. Build the language server (from ../java-ls):

   mvn -pl java-ls -am package
   

   Produces ../java-ls/java-ls/target/java-ls.jar.

3. Compile the extension:

   npm run compile
   

   For iterative work, use npm run watch instead (TypeScript check + esbuild).

Run

1. Open this folder in VS Code / Cursor.
2. Press F5 (or Run and Debug → Run Extension).
3. In the Extension Development Host, open a Java file — the server starts automatically.

With default javals.serverMode: auto, the extension uses the sibling Maven jar when present, otherwise the bundled server/java-ls.jar.

After changing the server, rebuild it with Maven and run JavaLS: Restart Language Server from the command palette.

Package (VSIX)

# Ensure the server jar exists first (step 2 above)
npm run package

vscode:prepublish runs npm run sync-server, which copies ../java-ls/java-ls/target/java-ls.jar → ./server/java-ls.jar.

Override the source project with:

JAVALS_DEV_PROJECT=../some/other/path npm run sync-server

Settings

Commands

• JavaLS: Restart Language Server (javals.restartServer)
• JavaLS: Show Output Channel (javals.showOutputChannel)