diff --git a/src/java.base/share/classes/java/util/regex/Pattern.java b/src/java.base/share/classes/java/util/regex/Pattern.java
index 054ad4d9da0..9b9bdce8960 100644
--- a/src/java.base/share/classes/java/util/regex/Pattern.java
+++ b/src/java.base/share/classes/java/util/regex/Pattern.java
@@ -5541,10 +5541,10 @@ loop:   for(int x=0, offset=0; x<nCodePoints; x++, offset+=len) {
      * they are ignored for purposes of finding word boundaries.
      */
     static final class Bound extends Node {
-        static int LEFT = 0x1;
-        static int RIGHT= 0x2;
-        static int BOTH = 0x3;
-        static int NONE = 0x4;
+        static final int LEFT = 0x1;
+        static final int RIGHT= 0x2;
+        static final int BOTH = 0x3;
+        static final int NONE = 0x4;
         int type;
         boolean useUWORD;
         Bound(int n, boolean useUWORD) {