--- old/src/java.base/share/classes/sun/security/x509/X509CertImpl.java	2014-08-21 20:46:26.000000000 +0800
+++ new/src/java.base/share/classes/sun/security/x509/X509CertImpl.java	2014-08-21 20:46:25.000000000 +0800
@@ -802,11 +802,11 @@
         StringBuilder sb = new StringBuilder();
 
         sb.append("[\n");
-        sb.append(info.toString() + "\n");
-        sb.append("  Algorithm: [" + algId.toString() + "]\n");
+        sb.append(info.toString()).append('\n');
+        sb.append("  Algorithm: [").append(algId.toString()).append("]\n");
 
         HexDumpEncoder encoder = new HexDumpEncoder();
-        sb.append("  Signature:\n" + encoder.encodeBuffer(signature));
+        sb.append("  Signature:\n").append(encoder.encodeBuffer(signature));
         sb.append("\n]");
 
         return sb.toString();