[FLINK-39151][metrics] Hide warning about UnixOperatingSystemMXBean missing on Windows (#27662)

Author: piotrp

flink-runtime/src/main/java/org/apache/flink/runtime/metrics/util/MetricUtils.java

@@ -38,6 +38,7 @@
 import org.apache.flink.runtime.rpc.RpcSystem;
 import org.apache.flink.runtime.taskexecutor.slot.SlotNotFoundException;
 import org.apache.flink.runtime.taskexecutor.slot.TaskSlotTable;
+import org.apache.flink.util.OperatingSystem;
 import org.apache.flink.util.Preconditions;
 
 import org.slf4j.Logger;
@@ -88,6 +89,8 @@ public class MetricUtils {
     private static final String WRITER_SUFFIX = ": " + ConfigConstants.WRITER_NAME;
     private static final String COMMITTER_SUFFIX = ": " + ConfigConstants.COMMITTER_NAME;
 
+    private static Boolean fileDescriptorWarningShown = false;
+
     private MetricUtils() {}
 
     public static ProcessMetricGroup instantiateProcessMetricGroup(
@@ -340,6 +343,13 @@ static void instantiateMetaspaceMemoryMetrics(final MetricGroup parentMetricGrou
     }
 
     static void instantiateFileDescriptorMetrics(MetricGroup metrics) {
+        if (OperatingSystem.isWindows()) {
+            if (!fileDescriptorWarningShown) {
+                fileDescriptorWarningShown = true;
+                LOG.info("Running on Windows, FileDescriptor metrics will not be available.");
+            }
+            return;
+        }
         try {
             final com.sun.management.OperatingSystemMXBean mxBean =
                     (com.sun.management.OperatingSystemMXBean)

flink-runtime/src/test/java/org/apache/flink/runtime/metrics/util/MetricUtilsTest.java

@@ -42,6 +42,8 @@
 
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.DisabledOnOs;
+import org.junit.jupiter.api.condition.OS;
 
 import javax.management.ObjectName;
 
@@ -178,6 +180,7 @@ void testHeapMetricsCompleteness() {
     }
 
     @Test
+    @DisabledOnOs(OS.WINDOWS)
     void testFileDescriptorMetricsCompleteness() {
         final InterceptingOperatorMetricGroup heapMetrics = new InterceptingOperatorMetricGroup();