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 692d688..853a597 100644
--- a/utils/misc/src/main/java/org/onlab/util/HexDump.java
+++ b/utils/misc/src/main/java/org/onlab/util/HexDump.java
@@ -43,7 +43,7 @@
                 StringBuilder sb = new StringBuilder();
                 for (int k = 0; (k < 16) && (buff.readableBytes() != 0); ++k) {
                     if (0 == k % 4) {
-                        sb.append(String.format(" ")); // blank after 4 bytes
+                        sb.append(" "); // blank after 4 bytes
                     }
                     sb.append(String.format("%02X ", buff.readByte()));
                 }