diff --git a/src/java/org/apache/commons/lang/text/translate/UnicodeUnescaper.java b/src/java/org/apache/commons/lang/text/translate/UnicodeUnescaper.java
index de903b869..08c4602f7 100644
--- a/src/java/org/apache/commons/lang/text/translate/UnicodeUnescaper.java
+++ b/src/java/org/apache/commons/lang/text/translate/UnicodeUnescaper.java
@@ -31,7 +31,7 @@ public class UnicodeUnescaper extends CharSequenceTranslator {
 
     public static enum OPTION { escapePlus };
 
-    private EnumSet<OPTION> options;
+    private final EnumSet<OPTION> options;
 
     public UnicodeUnescaper(OPTION... options) {
         if(options.length > 0) {