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

Change-Id: I17d72338d4202117d08b3dca9463be35a87a0c1e
diff --git a/utils/misc/src/main/java/org/onlab/packet/TCP.java b/utils/misc/src/main/java/org/onlab/packet/TCP.java
index e089f27..6f9f6df 100644
--- a/utils/misc/src/main/java/org/onlab/packet/TCP.java
+++ b/utils/misc/src/main/java/org/onlab/packet/TCP.java
@@ -21,6 +21,7 @@
 import java.nio.ByteBuffer;
 import java.util.Arrays;
 
+import static com.google.common.base.MoreObjects.toStringHelper;
 import static org.onlab.packet.PacketUtils.*;
 
 /**
@@ -459,4 +460,20 @@
             return tcp;
         };
     }
+
+    @Override
+    public String toString() {
+        return toStringHelper(getClass())
+                .add("sourcePort", Integer.toString(sourcePort))
+                .add("destinationPort", Integer.toString(destinationPort))
+                .add("sequence", Integer.toString(sequence))
+                .add("acknowledge", Integer.toString(acknowledge))
+                .add("dataOffset", Byte.toString(dataOffset))
+                .add("flags", Short.toString(flags))
+                .add("windowSize", Short.toString(windowSize))
+                .add("checksum", Short.toString(checksum))
+                .add("urgentPointer", Short.toString(urgentPointer))
+                .add("options", Arrays.toString(options))
+                .toString();
+    }
 }