diff --git a/src/main/java/org/apache/commons/codec/language/bm/Rule.java b/src/main/java/org/apache/commons/codec/language/bm/Rule.java
index 3ea1ef9..1939945 100644
--- a/src/main/java/org/apache/commons/codec/language/bm/Rule.java
+++ b/src/main/java/org/apache/commons/codec/language/bm/Rule.java
@@ -581,7 +581,7 @@
         }
 
         return new RPattern() {
-            Pattern pattern = Pattern.compile(regex);
+            final Pattern pattern = Pattern.compile(regex);
 
             @Override
             public boolean isMatch(final CharSequence input) {