JDTLS Rust Proxy (#214)

A new proxy written entirely in Rust.

Motivation

- **Eliminates the Node.js runtime dependency** 
- **Faster cold start** as no V8 JIT warmup
- **Lower memory footprint** as no garbage collector overhead

Author: tartarughina

.github/workflows/release-proxy.yml

@@ -0,0 +1,85 @@
+name: Release Proxy Binary
+
+on:
+  release:
+    types: [published]
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    name: Build ${{ matrix.asset_name }}
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: true
+      matrix:
+        include:
+          - target: aarch64-apple-darwin
+            runner: macos-14
+            asset_name: java-lsp-proxy-darwin-aarch64.tar.gz
+          - target: x86_64-apple-darwin
+            runner: macos-15-intel
+            asset_name: java-lsp-proxy-darwin-x86_64.tar.gz
+          - target: x86_64-unknown-linux-gnu
+            runner: ubuntu-latest
+            asset_name: java-lsp-proxy-linux-x86_64.tar.gz
+          - target: aarch64-unknown-linux-gnu
+            runner: ubuntu-24.04-arm
+            asset_name: java-lsp-proxy-linux-aarch64.tar.gz
+          - target: x86_64-pc-windows-msvc
+            runner: windows-latest
+            asset_name: java-lsp-proxy-windows-x86_64.zip
+          - target: aarch64-pc-windows-msvc
+            runner: windows-11-arm
+            asset_name: java-lsp-proxy-windows-aarch64.zip
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: ${{ matrix.target }}
+
+      - name: Build proxy binary
+        working-directory: proxy
+        run: cargo build --release --target ${{ matrix.target }}
+        shell: bash
+
+      - name: Package binary (Unix)
+        if: runner.os != 'Windows'
+        run: |
+          tar -czf ${{ matrix.asset_name }} \
+            -C target/${{ matrix.target }}/release \
+            java-lsp-proxy
+
+      - name: Package binary (Windows)
+        if: runner.os == 'Windows'
+        shell: pwsh
+        run: |
+          Compress-Archive -Path target/${{ matrix.target }}/release/java-lsp-proxy.exe -DestinationPath ${{ matrix.asset_name }}
+
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.asset_name }}
+          path: ${{ matrix.asset_name }}
+          retention-days: 1
+
+  release:
+    name: Create Release
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download all artifacts
+        uses: actions/download-artifact@v4
+        with:
+          path: artifacts
+          merge-multiple: true
+
+      - name: Upload release assets
+        uses: softprops/action-gh-release@v2
+        with:
+          files: artifacts/*

.gitignore

@@ -1,4 +1,5 @@
 grammars/
 target/
+proxy/target/
 extension.wasm
 .DS_Store

Cargo.lock

@@ -1,3 +1,8 @@
+[workspace]
+members = [
+    ".",
+    "proxy"
+]
 
 [package]
 name = "zed_java"

Cargo.toml

@@ -0,0 +1,33 @@
+native_target := `rustc -vV | grep host | awk '{print $2}'`
+ext_dir := if os() == "macos" { env("HOME") / "Library/Application Support/Zed/extensions/work/java" } else if os() == "linux" { env("HOME") / ".local/share/zed/extensions/work/java" } else { env("LOCALAPPDATA") / "Zed/extensions/work/java" }
+proxy_bin := ext_dir / "proxy-bin" / "java-lsp-proxy"
+
+# Build proxy in debug mode
+proxy-build:
+    cd proxy && cargo build --target {{ native_target }}
+
+# Build proxy in release mode
+proxy-release:
+    cd proxy && cargo build --release --target {{ native_target }}
+
+# Build proxy release and install to extension workdir for testing
+proxy-install: proxy-release
+    mkdir -p "{{ ext_dir }}/proxy-bin"
+    cp "target/{{ native_target }}/release/java-lsp-proxy" "{{ proxy_bin }}"
+    @echo "Installed to {{ proxy_bin }}"
+
+# Build WASM extension in release mode
+ext-build:
+    cargo build --release
+
+# Format all code
+fmt:
+    cargo fmt --all
+
+# Run clippy on both crates
+clippy:
+    cargo clippy --all-targets --fix --allow-dirty
+    cd proxy && cargo clippy --all-targets --fix --allow-dirty --target {{ native_target }}
+
+# Build everything: fmt, clippy, extension, proxy install
+all: fmt clippy ext-build proxy-install

justfile

@@ -0,0 +1,7 @@
+[build]
+target = "aarch64-apple-darwin"
+# target = "x86_64-apple-darwin"
+# target = "x86_64-unknown-linux-gnu"
+# target = "aarch64-unknown-linux-gnu"
+# target = "x86_64-pc-windows-msvc"
+# target = "aarch64-pc-windows-msvc"