Optimize CI by using a custom Docker container with pre-installed dependencies.

This change introduces a Docker container (`.ci/container/Dockerfile`) that pre-installs:
- OpenJDK 8 (ZuluFX), 11, 17, 21, and 25 (Zulu).
- Ant, Maven, Python 3.
- Codename One binaries (`cn1-binaries`).
- Required libraries for headless UI testing (xvfb, libgl1-mesa-dri).

Updates `pr.yml`, `ant.yml`, and `scripts-android.yml` to run jobs inside this container, removing redundant setup steps (JDK download, tool installation) to improve build speed and reproducibility.

Also updates `scripts/setup-workspace.sh` to respect the `CN1_BINARIES` environment variable and handle the pre-configured environment correctly.

Author: google-labs-jules[bot]

.ci/container/Dockerfile

@@ -0,0 +1,74 @@
+FROM ubuntu:24.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install basics and tools
+RUN apt-get update && apt-get install -y \
+    curl \
+    wget \
+    gnupg \
+    ca-certificates \
+    git \
+    unzip \
+    zip \
+    python3 \
+    python3-pip \
+    xvfb \
+    libgl1-mesa-dri \
+    libxtst6 \
+    libxxf86vm1 \
+    ant \
+    maven \
+    && rm -rf /var/lib/apt/lists/*
+
+# Setup Azul Repo
+RUN curl -s https://repos.azul.com/azul-repo.key | gpg --dearmor -o /usr/share/keyrings/azul.gpg \
+    && echo "deb [signed-by=/usr/share/keyrings/azul.gpg] https://repos.azul.com/zulu/deb stable main" | tee /etc/apt/sources.list.d/zulu.list
+
+# Install JDKs 11, 17, 21, 25
+RUN apt-get update && apt-get install -y \
+    zulu11-jdk \
+    zulu17-jdk \
+    zulu21-jdk \
+    zulu25-jdk \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install ZuluFX 8 (Tarball)
+# URL for Zulu 8 + FX (x64 Linux)
+# Using a fixed version to ensure reproducibility.
+RUN mkdir -p /usr/lib/jvm/zulu8-fx && \
+    curl -L "https://cdn.azul.com/zulu/bin/zulu8.82.0.21-ca-fx-jdk8.0.432-linux_x64.tar.gz" -o /tmp/zulu8.tar.gz && \
+    tar -xzf /tmp/zulu8.tar.gz -C /usr/lib/jvm/zulu8-fx --strip-components=1 && \
+    rm /tmp/zulu8.tar.gz
+
+# Clone cn1-binaries
+RUN git clone --depth=1 https://github.com/codenameone/cn1-binaries /opt/cn1-binaries
+
+# Set Environment Variables
+ENV JAVA_HOME=/usr/lib/jvm/zulu8-fx
+ENV PATH=$JAVA_HOME/bin:$PATH
+
+ENV JAVA8_HOME=/usr/lib/jvm/zulu8-fx
+ENV JDK8_HOME=/usr/lib/jvm/zulu8-fx
+
+# Paths for apt installed JDKs (usually symlinked to /usr/lib/jvm/zulu-XX-amd64)
+ENV JAVA11_HOME=/usr/lib/jvm/zulu-11-amd64
+ENV JDK11_HOME=/usr/lib/jvm/zulu-11-amd64
+ENV JAVA17_HOME=/usr/lib/jvm/zulu-17-amd64
+ENV JDK17_HOME=/usr/lib/jvm/zulu-17-amd64
+ENV JAVA21_HOME=/usr/lib/jvm/zulu-21-amd64
+ENV JDK21_HOME=/usr/lib/jvm/zulu-21-amd64
+ENV JAVA25_HOME=/usr/lib/jvm/zulu-25-amd64
+ENV JDK25_HOME=/usr/lib/jvm/zulu-25-amd64
+
+ENV CN1_BINARIES=/opt/cn1-binaries
+
+# Verify installations
+RUN java -version && \
+    $JAVA11_HOME/bin/java -version && \
+    $JAVA17_HOME/bin/java -version && \
+    $JAVA21_HOME/bin/java -version && \
+    $JAVA25_HOME/bin/java -version && \
+    ant -version && \
+    mvn -version && \
+    python3 --version

.github/workflows/ant.yml

@@ -11,16 +11,11 @@ jobs:
   build-linux-jdk8:
 
     runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/${{ github.repository }}/ci-container:latest
 
     steps:
     - uses: actions/checkout@v1
-    - name: Set up JDK 8
-      uses: actions/setup-java@v1
-      with:
-        java-version: 1.8
-        java-package: jdk
-    - name: Install dependencies
-      run: sudo apt-get update && sudo apt-get install xvfb
     - name: Build with Maven
       run: |
         cd maven

.github/workflows/build-container.yml

@@ -0,0 +1,37 @@
+name: Build CI Container
+
+on:
+  push:
+    paths:
+      - '.ci/container/**'
+      - '.github/workflows/build-container.yml'
+  workflow_dispatch:
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}/ci-container
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .ci/container
+          push: true
+          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest

.github/workflows/pr.yml

@@ -37,14 +37,11 @@ jobs:
   build-linux-jdk8-fx:
 
     runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/${{ github.repository }}/ci-container:latest
 
     steps:
     - uses: actions/checkout@v1
-    - name: Set up JDK 8
-      uses: actions/setup-java@v1
-      with:
-        java-version: 1.8
-        java-package: jdk+fx
     - name: Cache Maven dependencies
       uses: actions/cache@v4
       with:
@@ -57,15 +54,10 @@ jobs:
         cd maven
         mvn clean verify -DunitTests=true -pl core-unittests -am -Dmaven.javadoc.skip=true -Plocal-dev-javase
         cd ..
-    - name: Prepare Codename One binaries for Maven plugin tests
-      run: |
-        set -euo pipefail
-        rm -rf maven/target/cn1-binaries
-        git clone --depth=1 --filter=blob:none https://github.com/codenameone/cn1-binaries maven/target/cn1-binaries
     - name: Run Maven plugin tests
       working-directory: maven
       env:
-        CN1_BINARIES: ${{ github.workspace }}/maven/target/cn1-binaries
+        CN1_BINARIES: /opt/cn1-binaries
       run: |
         mvn -B -Dmaven.javadoc.skip=true \
           -DunitTests=true \
@@ -211,12 +203,6 @@ jobs:
         script: |
           const { publishQualityComment } = require('./.github/scripts/publish-quality-comment.js');
           await publishQualityComment({ github, context, core });
-    - name: Install dependencies
-      run: |
-        sudo apt-get update && sudo apt-get install xvfb
-        wget https://github.com/codenameone/cn1-binaries/archive/refs/heads/master.zip
-        unzip master.zip -d ..
-        mv ../cn1-binaries-master ../cn1-binaries
     - name: Build with Ant
       run: xvfb-run ant test-javase
     - name: Build CLDC11 JAR

.github/workflows/scripts-android.yml

@@ -90,6 +90,9 @@ jobs:
       pull-requests: write
       issues: write
     runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/${{ github.repository }}/ci-container:latest
+      options: --privileged -v /dev/kvm:/dev/kvm
     env:
       GITHUB_TOKEN: ${{ secrets.CN1SS_GH_TOKEN }}
       GH_TOKEN: ${{ secrets.CN1SS_GH_TOKEN }}
@@ -98,19 +101,13 @@ jobs:
       - name: Free Disk Space
         if: matrix.id != 'default'
         run: |
-          sudo rm -rf /usr/share/dotnet
-          sudo rm -rf /usr/local/lib/android/sdk/ndk
-          sudo rm -rf /opt/ghc
-          sudo rm -rf /usr/share/swift
-      - name: Setup JDK
-        if: matrix.id != 'default'
-        uses: actions/setup-java@v4
-        with:
-          java-version: ${{ matrix.java_version }}
-          distribution: 'zulu'
+          rm -rf /usr/share/dotnet
+          rm -rf /usr/local/lib/android/sdk/ndk
+          rm -rf /opt/ghc
+          rm -rf /usr/share/swift
       - name: Set JDK_HOME
         if: matrix.id != 'default'
-        run: echo "JDK_HOME=${JAVA_HOME}" >> $GITHUB_ENV
+        run: echo "JDK_HOME=/usr/lib/jvm/zulu-${{ matrix.java_version }}-amd64" >> $GITHUB_ENV
       - name: Configure CN1SS options
         if: matrix.id != 'default'
         run: |

scripts/setup-workspace.sh

@@ -22,8 +22,11 @@ ENV_DIR="$DOWNLOAD_DIR/tools"
 mkdir -p "$DOWNLOAD_DIR"
 mkdir -p "$ENV_DIR"
 CN1_BINARIES_PARENT="$(cd .. && pwd -P)"
-CN1_BINARIES="${CN1_BINARIES_PARENT%/}/cn1-binaries"
-mkdir -p "$CN1_BINARIES_PARENT"
+CN1_BINARIES="${CN1_BINARIES:-${CN1_BINARIES_PARENT%/}/cn1-binaries}"
+if [[ "$CN1_BINARIES" != /* ]]; then
+  CN1_BINARIES="$(cd "${CN1_BINARIES%/*}" && pwd -P)/${CN1_BINARIES##*/}"
+fi
+mkdir -p "$(dirname "$CN1_BINARIES")"
 
 ENV_FILE="$ENV_DIR/env.sh"
 
@@ -183,36 +186,43 @@ log "Maven version:"; "$MAVEN_HOME/bin/mvn" -version
 PATH="$JAVA_HOME/bin:$MAVEN_HOME/bin:$PATH"
 
 log "Preparing cn1-binaries checkout"
-if [ -d "$CN1_BINARIES/.git" ]; then
+if [ "${CN1_SKIP_BINARIES_UPDATE:-0}" = "1" ]; then
+  log "Skipping cn1-binaries update as requested"
+elif [ -d "$CN1_BINARIES/.git" ]; then
   log "Found existing cn1-binaries repository at $CN1_BINARIES"
   if git -C "$CN1_BINARIES" remote get-url origin >/dev/null 2>&1; then
-    if git -C "$CN1_BINARIES" fetch --depth=1 origin; then
-      remote_head=$(git -C "$CN1_BINARIES" symbolic-ref --quiet --short refs/remotes/origin/HEAD 2>/dev/null || true)
-      if [ -z "$remote_head" ]; then
-        current_branch=$(git -C "$CN1_BINARIES" rev-parse --abbrev-ref HEAD 2>/dev/null || true)
-        if [ -n "$current_branch" ] && [ "$current_branch" != "HEAD" ]; then
-          remote_head="origin/$current_branch"
-        else
-          remote_head="origin/master"
-        fi
-      fi
-      if ! git -C "$CN1_BINARIES" rev-parse --verify "$remote_head" >/dev/null 2>&1; then
-        if git -C "$CN1_BINARIES" rev-parse --verify origin/main >/dev/null 2>&1; then
-          remote_head="origin/main"
-        elif git -C "$CN1_BINARIES" rev-parse --verify origin/master >/dev/null 2>&1; then
-          remote_head="origin/master"
+    # Check if directory is writable before attempting update
+    if [ -w "$CN1_BINARIES" ] && [ -w "$CN1_BINARIES/.git" ]; then
+        if git -C "$CN1_BINARIES" fetch --depth=1 origin; then
+          remote_head=$(git -C "$CN1_BINARIES" symbolic-ref --quiet --short refs/remotes/origin/HEAD 2>/dev/null || true)
+          if [ -z "$remote_head" ]; then
+            current_branch=$(git -C "$CN1_BINARIES" rev-parse --abbrev-ref HEAD 2>/dev/null || true)
+            if [ -n "$current_branch" ] && [ "$current_branch" != "HEAD" ]; then
+              remote_head="origin/$current_branch"
+            else
+              remote_head="origin/master"
+            fi
+          fi
+          if ! git -C "$CN1_BINARIES" rev-parse --verify "$remote_head" >/dev/null 2>&1; then
+            if git -C "$CN1_BINARIES" rev-parse --verify origin/main >/dev/null 2>&1; then
+              remote_head="origin/main"
+            elif git -C "$CN1_BINARIES" rev-parse --verify origin/master >/dev/null 2>&1; then
+              remote_head="origin/master"
+            else
+              log "Unable to determine remote head for cached cn1-binaries; removing checkout"
+              rm -rf "$CN1_BINARIES"
+            fi
+          fi
+          if [ -d "$CN1_BINARIES/.git" ]; then
+            log "Updating cn1-binaries to $remote_head"
+            git -C "$CN1_BINARIES" reset --hard "$remote_head"
+          fi
         else
-          log "Unable to determine remote head for cached cn1-binaries; removing checkout"
+          log "Failed to fetch updates for cached cn1-binaries; removing checkout"
           rm -rf "$CN1_BINARIES"
         fi
-      fi
-      if [ -d "$CN1_BINARIES/.git" ]; then
-        log "Updating cn1-binaries to $remote_head"
-        git -C "$CN1_BINARIES" reset --hard "$remote_head"
-      fi
     else
-      log "Failed to fetch updates for cached cn1-binaries; removing checkout"
-      rm -rf "$CN1_BINARIES"
+        log "cn1-binaries directory is not writable. Skipping update."
     fi
   else
     log "Cached cn1-binaries checkout missing origin remote; removing"