Make Package private class static.
diff --git a/src/main/java/org/apache/commons/codec/language/ColognePhonetic.java b/src/main/java/org/apache/commons/codec/language/ColognePhonetic.java
index 73d77bd..48cc5ec 100644
--- a/src/main/java/org/apache/commons/codec/language/ColognePhonetic.java
+++ b/src/main/java/org/apache/commons/codec/language/ColognePhonetic.java
@@ -199,7 +199,7 @@
      * However, it is not shared between threads, as it is constructed on demand
      * by the method {@link ColognePhonetic#colognePhonetic(String)}
      */
-    abstract class CologneBuffer {
+    abstract static class CologneBuffer {
 
         protected final char[] data;