Configure JDK 21 CI build

This commit replaces the JDK 20 compatibility build with a JDK 21 (early
access) variant.

See gh-30339

ci/images/ci-image/Dockerfile

@@ -6,6 +6,6 @@ RUN ./setup.sh
 
 ENV JAVA_HOME /opt/openjdk/java17
 ENV JDK17 /opt/openjdk/java17
-ENV JDK20 /opt/openjdk/java20
+ENV JDK21 /opt/openjdk/java20
 
 ENV PATH $JAVA_HOME/bin:$PATH

ci/images/get-jdk-url.sh

@@ -8,6 +8,9 @@ case "$1" in
 	java20)
 		echo "https://github.com/bell-sw/Liberica/releases/download/20%2B37/bellsoft-jdk20+37-linux-amd64.tar.gz"
 	;;
+  java21)
+    echo "https://download.java.net/java/early_access/jdk21/18/GPL/openjdk-21-ea+18_linux-x64_bin.tar.gz"
+  ;;
 	*)
 		echo $"Unknown java version"
 		exit 1

ci/pipeline.yml

@@ -127,14 +127,14 @@ resources:
     access_token: ((github-ci-status-token))
     branch: ((branch))
     context: build
-- name: repo-status-jdk20-build
+- name: repo-status-jdk21-build
   type: github-status-resource
   icon: eye-check-outline
   source:
     repository: ((github-repo-name))
     access_token: ((github-ci-status-token))
     branch: ((branch))
-    context: jdk20-build
+    context: jdk21-build
 - name: slack-alert
   type: slack-notification
   icon: slack
@@ -231,7 +231,7 @@ jobs:
           "zip.type": "schema"
     get_params:
       threads: 8
-- name: jdk20-build
+- name: jdk21-build
   serial: true
   public: true
   plan:
@@ -239,7 +239,7 @@ jobs:
     - get: git-repo
     - get: every-morning
       trigger: true
-    - put: repo-status-jdk20-build
+    - put: repo-status-jdk21-build
       params: { state: "pending", commit: "git-repo" }
     - do:
         - task: check-project
@@ -248,16 +248,16 @@ jobs:
           privileged: true
           timeout: ((task-timeout))
           params:
-            TEST_TOOLCHAIN: 20
+            TEST_TOOLCHAIN: 21
             <<: *build-project-task-params
       on_failure:
         do:
-          - put: repo-status-jdk20-build
+          - put: repo-status-jdk21-build
             params: { state: "failure", commit: "git-repo" }
           - put: slack-alert
             params:
               <<: *slack-fail-params
-    - put: repo-status-jdk20-build
+    - put: repo-status-jdk21-build
       params: { state: "success", commit: "git-repo" }
 - name: build-pull-requests
   serial: true
@@ -441,7 +441,7 @@ jobs:
 
 groups:
 - name: "builds"
-  jobs: ["build", "jdk20-build"]
+  jobs: ["build", "jdk21-build"]
 - name: "releases"
   jobs: ["stage-milestone", "stage-rc", "stage-release", "promote-milestone", "promote-rc", "promote-release", "create-github-release"]
 - name: "ci-images"

ci/scripts/check-project.sh

@@ -4,6 +4,6 @@ set -e
 source $(dirname $0)/common.sh
 
 pushd git-repo > /dev/null
-./gradlew -Dorg.gradle.internal.launcher.welcomeMessageEnabled=false -Porg.gradle.java.installations.fromEnv=JDK17,JDK20 \
+./gradlew -Dorg.gradle.internal.launcher.welcomeMessageEnabled=false -Porg.gradle.java.installations.fromEnv=JDK17,JDK21 \
   -PmainToolchain=${MAIN_TOOLCHAIN} -PtestToolchain=${TEST_TOOLCHAIN} --no-daemon --max-workers=4 check
 popd > /dev/null