Build/test with GitHub Actions.

.github/workflows/test.yml

@@ -0,0 +1,29 @@
+name: Build/test
+
+on: [push]
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-20.04]
+        java: [8, 11, 13, 15]
+      fail-fast: false
+    name: JDK ${{ matrix.java }}
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Set up JDK
+      uses: actions/setup-java@v1
+      with:
+        java-version: ${{ matrix.java }}
+    - name: Cache local Maven repository
+      uses: actions/cache@v2
+      with:
+        path: ~/.m2/repository
+        key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+        restore-keys: |
+          ${{ runner.os }}-maven-
+    - name: Test with Maven
+      run: mvn verify -B --file pom.xml