Lookup key in map only once

Author: garydgregory

src/main/java/org/apache/commons/codec/language/DaitchMokotoffSoundex.java

@@ -361,8 +361,9 @@ private String cleanup(final String input) {
             }
 
             ch = Character.toLowerCase(ch);
-            if (folding && FOLDINGS.containsKey(ch)) {
-                ch = FOLDINGS.get(ch);
+            final Character character = FOLDINGS.get(ch);
+            if (folding && character != null) {
+                ch = character;
             }
             sb.append(ch);
         }