Depreacte FileSystemUtils 0-argument contructor
diff --git a/src/main/java/org/apache/commons/io/FileSystemUtils.java b/src/main/java/org/apache/commons/io/FileSystemUtils.java
index 8a244ec..2b959ff 100644
--- a/src/main/java/org/apache/commons/io/FileSystemUtils.java
+++ b/src/main/java/org/apache/commons/io/FileSystemUtils.java
@@ -242,8 +242,12 @@
 
     /**
      * Instances should NOT be constructed in standard programming.
+     *
+     * @deprecated TODO Make private in 4.0.
      */
+    @Deprecated
     public FileSystemUtils() {
+        // empty
     }
 
     /**