Index: org/apache/tomcat/util/IntrospectionUtils.java
===================================================================
--- org/apache/tomcat/util/IntrospectionUtils.java	(revision 831814)
+++ org/apache/tomcat/util/IntrospectionUtils.java	(working copy)
@@ -492,7 +492,7 @@
         if (value.indexOf("$") < 0) {
             return value;
         }
-        StringBuffer sb = new StringBuffer();
+        StringBuilder sb = new StringBuilder();
         int prev = 0;
         // assert value!=nil
         int pos;
@@ -957,8 +957,8 @@
 
         if (dbg > 0) {
             // debug
-            StringBuffer sb = new StringBuffer();
-            sb.append("" + target.getClass().getName() + "." + methodN + "( ");
+            StringBuilder sb = new StringBuilder();
+            sb.append(target.getClass().getName()).append(".").append(methodN).append("( ");
             for (int i = 0; i < params.length; i++) {
                 if (i > 0)
                     sb.append(", ");