chore: Java 8 unit test to build code in Java 17 and run tests on Java 8 (#1800) (#1381)

* Our Java projects are configured to produce Java 8-compatible bytecode via https://togithub.com/googleapis/java-shared-config/blob/main/pom.xml#L848. This unit test change ensures this config is applied correctly.

* For the repositories that mark "dependencies (8)" and "dependencies (11)" as required, they should point to only "dependencies (17)" via `.github/sync-repo-settings.yaml` and repo's Settings tab.
Source-Link: https://togithub.com/googleapis/synthtool/commit/cbe010084fc59dc15730c86e9b8e03ddac1de050
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-java:latest@sha256:32851debfefed2b66038e0141f1b5c2103bb59ba80b7475adbc10ef7abab3de7

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-java:latest
-  digest: sha256:c33bd13e1eab022b0499a3afbfb4b93ae10cb8ad89d8203a6343a88b1b78400f
-# created: 2023-06-21T18:48:32.287298785Z
+  digest: sha256:32851debfefed2b66038e0141f1b5c2103bb59ba80b7475adbc10ef7abab3de7
+# created: 2023-06-22T15:06:52.039318836Z

.github/sync-repo-settings.yaml

@@ -8,8 +8,7 @@ branchProtectionRules:
     requiresCodeOwnerReviews: true
     requiresStrictStatusChecks: false
     requiredStatusCheckContexts:
-      - dependencies (8)
-      - dependencies (11)
+      - dependencies (17)
       - lint
       - clirr
       - units (8)

.github/workflows/ci.yaml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java: [8, 11, 17]
+        java: [11, 17]
     steps:
     - uses: actions/checkout@v3
     - uses: actions/setup-java@v3
@@ -36,6 +36,28 @@ jobs:
     - run: .kokoro/build.sh
       env:
         JOB_TYPE: test
+  units-java8:
+    # Building using Java 17 and run the tests with Java 8 runtime
+    name: "units (8)"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v3
+        with:
+          java-version: 8
+          distribution: zulu
+      - name: "Set jvm system property environment variable for surefire plugin (unit tests)"
+        # Maven surefire plugin (unit tests) allows us to specify JVM to run the tests.
+        # https://maven.apache.org/surefire/maven-surefire-plugin/test-mojo.html#jvm
+        run: echo "SUREFIRE_JVM_OPT=-Djvm=${JAVA_HOME}/bin/java" >> $GITHUB_ENV
+        shell: bash
+      - uses: actions/setup-java@v3
+        with:
+          java-version: 17
+          distribution: zulu
+      - run: .kokoro/build.sh
+        env:
+          JOB_TYPE: test
   windows:
     runs-on: windows-latest
     steps:
@@ -54,7 +76,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [8, 11, 17]
+        java: [17]
     steps:
     - uses: actions/checkout@v3
     - uses: actions/setup-java@v3

.kokoro/build.sh

@@ -47,7 +47,8 @@ set +e
 
 case ${JOB_TYPE} in
 test)
-    mvn test -B -ntp -Dclirr.skip=true -Denforcer.skip=true
+    echo "SUREFIRE_JVM_OPT: ${SUREFIRE_JVM_OPT}"
+    mvn test -B -ntp -Dclirr.skip=true -Denforcer.skip=true ${SUREFIRE_JVM_OPT}
     RETURN_CODE=$?
     ;;
 lint)

README.md

@@ -59,13 +59,13 @@ implementation 'com.google.cloud:google-cloud-logging'
 If you are using Gradle without BOM, add this to your dependencies:
 
 ```Groovy
-implementation 'com.google.cloud:google-cloud-logging:3.15.3'
+implementation 'com.google.cloud:google-cloud-logging:3.15.4'
 ```
 
 If you are using SBT, add this to your dependencies:
 
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-logging" % "3.15.3"
+libraryDependencies += "com.google.cloud" % "google-cloud-logging" % "3.15.4"
 ```
 <!-- {x-version-update-end} -->
 
@@ -452,7 +452,7 @@ Java is a registered trademark of Oracle and/or its affiliates.
 [kokoro-badge-link-5]: http://storage.googleapis.com/cloud-devrel-public/java/badges/java-logging/java11.html
 [stability-image]: https://img.shields.io/badge/stability-stable-green
 [maven-version-image]: https://img.shields.io/maven-central/v/com.google.cloud/google-cloud-logging.svg
-[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-logging/3.15.3
+[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-logging/3.15.4
 [authentication]: https://github.com/googleapis/google-cloud-java#authentication
 [auth-scopes]: https://developers.google.com/identity/protocols/oauth2/scopes
 [predefined-iam-roles]: https://cloud.google.com/iam/docs/understanding-roles#predefined_roles