Improve the resiliency of the packet deserialization code.

Packet deserializers now check for malformed input while reading the byte
stream. Deserializers are re-implemented as functions that take a byte array
and return a packet object. The old IPacket.deserialize(...) methods have been
deprecated with the goal of eventually moving to immutable packet objects.
Unit tests have been implemented for all Deserializer functions.

ONOS-1589

Change-Id: I9073d5e6e7991e15d43830cfd810989256b71c56
diff --git a/utils/misc/src/main/java/org/onlab/packet/Deserializer.java b/utils/misc/src/main/java/org/onlab/packet/Deserializer.java
new file mode 100644
index 0000000..e0ef381
--- /dev/null
+++ b/utils/misc/src/main/java/org/onlab/packet/Deserializer.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onlab.packet;
+
+/**
+ * Function to deserialize a packet from a byte-based input stream.
+ */
+@FunctionalInterface
+public interface Deserializer<U extends IPacket> {
+
+    /**
+     * Deserialize a packet object from a byte array.
+     *
+     * @param data input array to take packet bytes from
+     * @param offset index where this packet header begins in the byte array
+     * @param length length of the packet header
+     * @return a deserialized packet object
+     * @throws DeserializationException if the packet cannot be deserialized
+     * from the input
+     */
+    U deserialize(byte[] data, int offset, int length) throws DeserializationException;
+}