8303175: (fs) Deprecate com.sun.nio.file.SensitivityWatchEventModifier for removal

Reviewed-by: lancea, alanb

Author: Brian Burkhalter

src/jdk.unsupported/share/classes/com/sun/nio/file/SensitivityWatchEventModifier.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -32,9 +32,18 @@
  * Defines the <em>sensitivity levels</em> when registering objects with a
  * watch service implementation that polls the file system.
  *
+ * @deprecated
+ * The sensitivity levels were historically used by polling-based
+ * {@link java.nio.file.WatchService WatchService} implementations to configure
+ * the polling interval. They are are no longer used. The {@code WatchService}
+ * implementations in the JDK ignore these {@link java.nio.file.WatchEvent
+ * WatchEvent} modifiers if they are specified when registering a directory
+ * to be watched.
+ *
  * @since 1.7
  */
 
+@Deprecated(since="21", forRemoval = true)
 public enum SensitivityWatchEventModifier implements Modifier {
     /**
      * High sensitivity.