Hex dump read for channel buffer

Change-Id: Ife5e49d488c9806e30530b48bb189f7e4a191e97
diff --git a/utils/misc/src/main/java/org/onlab/util/HexDump.java b/utils/misc/src/main/java/org/onlab/util/HexDump.java
index cfb7939..b40cf6e 100755
--- a/utils/misc/src/main/java/org/onlab/util/HexDump.java
+++ b/utils/misc/src/main/java/org/onlab/util/HexDump.java
@@ -34,24 +34,21 @@
      * @param buff buffer content to dump in hex format

      */

     public static void dump(ChannelBuffer buff) {

+        buff.markReaderIndex();

         try {

-            byte[] yTemp;

-            yTemp = buff.array();

-

-            int iStartIndex = buff.readerIndex();

-            int iEndIndex = buff.writerIndex();

             do {

                 StringBuilder sb = new StringBuilder();

-                for (int k = 0; (k < 16) && (iStartIndex < iEndIndex); ++k) {

+                for (int k = 0; (k < 16) && (buff.readableBytes() != 0); ++k) {

                     if (0 == k % 4) {

                         sb.append(String.format(" ")); // blank after 4 bytes

                     }

-                    sb.append(String.format("%02X ", yTemp[iStartIndex++]));

+                    sb.append(String.format("%02X ", buff.readByte()));

                 }

                 log.debug(sb.toString());

-            } while (iStartIndex < iEndIndex);

+            } while (buff.readableBytes() != 0);

         } catch (Exception e) {

             log.error("[HexDump] Invalid buffer: " + e.toString());

         }

+        buff.resetReaderIndex();

     }

 }