--- a/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/util/Extern.java	Wed Oct 10 18:34:46 2012 -0700
+++ b/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/util/Extern.java	Wed Oct 10 18:44:21 2012 -0700
@@ -277,7 +277,7 @@
                                 boolean relative)
                          throws IOException {
         BufferedReader in = new BufferedReader(new InputStreamReader(input));
-        StringBuffer strbuf = new StringBuffer();
+        StringBuilder strbuf = new StringBuilder();
         try {
             int c;
             while ((c = in.read()) >= 0) {