Add GitHub workflow for integration tests on multiple Java versions

.github/workflows/ci-java.yml

@@ -41,3 +41,9 @@ jobs:
         name: Check style with Spotless
         run:  ./mvnw spotless:check -Pintegration-test
 
+  integration-test:
+    needs: build
+    uses: ./.github/workflows/integration-test.yml
+    with:
+      java-versions: '[8, 11, 17, 21]'
+

.github/workflows/integration-test.yml

@@ -0,0 +1,60 @@
+name: Integration Tests
+
+on:
+  workflow_dispatch:
+    inputs:
+      java-versions:
+        description: 'JSON array of Java versions to test'
+        required: false
+        default: '[8, 11, 17, 21]'
+  workflow_call:
+    inputs:
+      java-versions:
+        description: 'JSON array of Java versions to test'
+        type: string
+        required: false
+        default: '[8, 11, 17, 21]'
+  schedule:
+    - cron: '0 3 * * 1-5'
+
+jobs:
+  integration-test:
+    runs-on: ubuntu-latest
+    timeout-minutes: 120
+    strategy:
+      fail-fast: false
+      matrix:
+        java: ${{ fromJSON(inputs.java-versions || '[8, 11, 17, 21]') }}
+    name: Java ${{ matrix.java }} integration test
+    steps:
+      - uses: actions/checkout@v7
+      - name: Prepare multi-module build
+        run: git submodule update --init --recursive
+      # Every job gets its own Cloud Foundry on KinD, so the matrix can run in parallel.
+      # The action deploys the kind-deployment ref given in `ref`, so keep both on the same commit.
+      - name: Set up Cloud Foundry
+        uses: cloudfoundry/kind-deployment/.github/actions/setup-cf@8f0e3947abd716fc73d4787ce83e74ab73fb86a9
+        with:
+          ref: 8f0e3947abd716fc73d4787ce83e74ab73fb86a9
+      - name: Set up Java
+        uses: actions/setup-java@v5
+        with:
+          distribution: liberica
+          java-version: ${{ matrix.java }}
+      - name: Cache Maven packages
+        uses: actions/cache@v6
+        with:
+          path: ~/.m2
+          key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
+          restore-keys: ${{ runner.os }}-m2
+      - name: Run integration tests
+        # CC_ADMIN_PASSWORD and UAA_ADMIN_SECRET are exported by setup-cf
+        env:
+          TEST_APIHOST: api.cf.127-0-0-1.nip.io
+          TEST_ADMIN_USERNAME: ccadmin
+          TEST_ADMIN_PASSWORD: ${{ env.CC_ADMIN_PASSWORD }}
+          TEST_ADMIN_CLIENTID: admin
+          TEST_ADMIN_CLIENTSECRET: ${{ env.UAA_ADMIN_SECRET }}
+          TEST_SKIPSSLVALIDATION: 'true'
+          TEST_QUOTAS_ROUTES_RESERVEDPORTS: '50'
+        run: ./mvnw -B -Pintegration-test test -Dgpg.skip