Add GitHub actions workflow

.github/workflows/gradle.yml

@@ -0,0 +1,45 @@
+# This workflow will build a Java project with Gradle
+# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-gradle
+
+name: Build SSHJ
+
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    name: Build with Java ${{ matrix.java }}
+    strategy:
+      matrix:
+        java: [ 8, 9 ]
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up JDK ${{ matrix.java }}
+      uses: actions/setup-java@v1
+      with:
+        java-version: ${{ matrix.java }}
+    - name: Grant execute permission for gradlew
+      run: chmod +x gradlew
+    - name: Build with Gradle
+      run: ./gradlew check
+  integration:
+    name: Integration test
+    needs: [build]
+    runs-on: [ubuntu-latest]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 8
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+      - name: Build with Gradle
+        run: ./gradlew integrationTest
+