Add and use Add IOCase.isCaseSensitive(IOCase).

Author: Gary Gregory

src/changes/changes.xml

@@ -53,10 +53,13 @@ The <action> type attribute can be add,update,fix,remove.
       </action>
       <!-- ADD -->
       <action dev="ggregory" type="add" due-to="Gary Gregory">
-        Add RegexFileFilter.toString().
+        Add and use RegexFileFilter.toString().
       </action>
       <action dev="ggregory" type="add" due-to="Gary Gregory">
-        Add RegexFileFilter.RegexFileFilter(Pattern, Function&lt;Path&gt;, String>)
+        Add and use RegexFileFilter.RegexFileFilter(Pattern, Function&lt;Path&gt;, String>)
+      </action>
+      <action dev="ggregory" type="add" due-to="Gary Gregory">
+        Add and use IOCase.isCaseSensitive(IOCase).
       </action>
     </release>
     <release version="2.9.0" date="2021-05-22" description="Java 8 required.">

src/main/java/org/apache/commons/io/IOCase.java

@@ -64,6 +64,17 @@ public enum IOCase {
      */
     SYSTEM("System", !FilenameUtils.isSystemWindows());
 
+    /**
+     * Tests for cases sensitivity in a null-safe manner.
+     * 
+     * @param caseSensitivity an IOCase.
+     * @return true if the input is non-null and {@link #isCaseSensitive()}.
+     * @since 2.10.0
+     */
+    public static boolean isCaseSensitive(final IOCase caseSensitivity) {
+        return caseSensitivity != null && !caseSensitivity.isCaseSensitive();
+    }
+
     /** Serialization version. */
     private static final long serialVersionUID = -6343169151696340687L;
 

src/main/java/org/apache/commons/io/filefilter/RegexFileFilter.java

@@ -91,7 +91,7 @@ private static Pattern compile(final String pattern, final int flags) {
      * @return Pattern compilation flags.
      */
     private static int toFlags(final IOCase caseSensitivity) {
-        return caseSensitivity != null && !caseSensitivity.isCaseSensitive() ? Pattern.CASE_INSENSITIVE : 0;
+        return IOCase.isCaseSensitive(caseSensitivity) ? Pattern.CASE_INSENSITIVE : 0;
     }
 
     /** The regular expression pattern that will be used to match file names. */