[ONOS-3222] Implement toString method for each Packet class

Change-Id: I17d72338d4202117d08b3dca9463be35a87a0c1e
diff --git a/utils/misc/src/test/java/org/onlab/packet/ICMP6Test.java b/utils/misc/src/test/java/org/onlab/packet/ICMP6Test.java
index 39ddc24..8616b48 100644
--- a/utils/misc/src/test/java/org/onlab/packet/ICMP6Test.java
+++ b/utils/misc/src/test/java/org/onlab/packet/ICMP6Test.java
@@ -18,6 +18,7 @@
 
 package org.onlab.packet;
 
+import org.apache.commons.lang3.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
@@ -107,4 +108,17 @@
         assertTrue(icmp61.equals(icmp61));
         assertFalse(icmp61.equals(icmp62));
     }
+
+    /**
+     * Tests toString.
+     */
+    @Test
+    public void testToStringIcmp6() throws Exception {
+        ICMP6 icmp6 = ICMP6.deserializer().deserialize(bytePacket, 0, bytePacket.length);
+        String str = icmp6.toString();
+
+        assertTrue(StringUtils.contains(str, "icmpType=" + ICMP6.ECHO_REQUEST));
+        assertTrue(StringUtils.contains(str, "icmpCode=" + (byte) 0x00));
+        assertTrue(StringUtils.contains(str, "checksum=" + (short) 0x82bc));
+    }
 }