Add JVM --add-opens flags for Flink PVR on Java 21 (#39303)

Author: aIbrahiim

.github/trigger_files/beam_PostCommit_Java_PVR_Flink_Streaming.json

@@ -1,5 +1,5 @@
 {
   "comment": "Modify this file in a trivial way to cause this test suite to run",
-  "modification": 1,
+  "modification": 2,
   "https://github.com/apache/beam/pull/32440": "test new datastream runner for batch"
 }

runners/flink/job-server/flink_job_server.gradle

@@ -239,6 +239,27 @@ tasks.register("validatesPortableRunner") {
   dependsOn validatesPortableRunnerStreamingCheckpoint
 }
 
+def flinkJobServerJvmArgs() {
+  def testJavaVer = project.findProperty('testJavaVersion') ? (project.property('testJavaVersion') as int) : JavaVersion.current().majorVersion.toInteger()
+  if (testJavaVer >= 17) {
+    return [
+      "--add-opens=java.base/sun.nio.ch=ALL-UNNAMED",
+      "--add-opens=java.base/java.nio=ALL-UNNAMED",
+      "--add-opens=java.base/java.util=ALL-UNNAMED",
+      "--add-opens=java.base/java.lang.invoke=ALL-UNNAMED",
+      "--add-opens=java.base/java.lang=ALL-UNNAMED",
+      "-Djava.security.manager=allow",
+    ]
+  }
+  return []
+}
+
+[validatesPortableRunnerDocker, validatesPortableRunnerBatchDataSet, validatesPortableRunnerBatch, validatesPortableRunnerStreaming, validatesPortableRunnerStreamingCheckpoint].each { task ->
+  task.configure {
+    jvmArgs += flinkJobServerJvmArgs()
+  }
+}
+
 def jobPort = BeamModulePlugin.getRandomPort()
 def artifactPort = BeamModulePlugin.getRandomPort()
 
@@ -270,7 +291,9 @@ def setupTask = project.tasks.register("flinkJobServerSetup", Exec) {
   }
 
   executable 'sh'
-  args '-c', "$pythonDir/scripts/run_job_server.sh stop --group_id ${project.name} && $pythonDir/scripts/run_job_server.sh start --group_id ${project.name} --job_port ${jobPort} --artifact_port ${artifactPort} --job_server_jar ${flinkJobServerJar} --additional_args \"${additionalArgs}\""
+  def jvmArgs = flinkJobServerJvmArgs().join(' ')
+  def jvmArgsOpt = jvmArgs ? "--jvm_args \"${jvmArgs}\"" : ""
+  args '-c', "$pythonDir/scripts/run_job_server.sh stop --group_id ${project.name} && $pythonDir/scripts/run_job_server.sh start --group_id ${project.name} --job_port ${jobPort} --artifact_port ${artifactPort} --job_server_jar ${flinkJobServerJar} --additional_args \"${additionalArgs}\" ${jvmArgsOpt}"
 }
 
 def cleanupTask = project.tasks.register("flinkJobServerCleanup", Exec) {