ci: test Maven build on Java 17

Author: ejboy

.github/workflows/ci.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    name: Maven tests (Java 17)
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+
+    steps:
+      - name: Check out source
+        uses: actions/checkout@v6
+
+      - name: Set up Java 17
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: '17'
+          cache: maven
+
+      - name: Build and test
+        run: mvn --batch-mode --no-transfer-progress clean verify