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+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2012 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ * 卞超轶 Chaoyi Bian <bcy@pku.edu.cn>
+ * Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef SYNC_LEAF_H
+#define SYNC_LEAF_H
+
+#include "sync-seq-no.h"
+#include <boost/shared_ptr.hpp>
+
+namespace ns3 {
+namespace Sync {
+
+class NameInfo;
+
+/**
+ * \ingroup sync
+ * @brief Sync tree leaf
+ */
+class Leaf
+{
+public:
+ /**
+ * @brief Constructor
+ * @param info Smart pointer to leaf's name
+ * @param seq Initial sequence number of the pointer
+ */
+ Leaf (boost::shared_ptr<const NameInfo> info, const SeqNo &seq)
+ : m_info (info)
+ , m_seq (seq)
+ { }
+
+ virtual ~Leaf ()
+ {
+ }
+
+ /**
+ * @brief Get name of the leaf
+ */
+ const NameInfo &
+ getInfo () const
+ {
+ return *m_info;
+ }
+
+ /**
+ * @brief Get sequence number of the leaf
+ */
+ const SeqNo&
+ getSeq () const
+ {
+ return m_seq;
+ }
+
+ /**
+ * @brief Update sequence number of the leaf
+ * @param seq Sequence number
+ *
+ * Sequence number is updated to the largest value among this->m_seq and seq
+ */
+ void
+ setSeq (const SeqNo &seq)
+ {
+ m_seq = std::max (m_seq, seq);
+ }
+
+private:
+ NameInfoConstPtr m_info;
+ SeqNo m_seq;
+};
+
+typedef boost::shared_ptr<Leaf> LeafPtr;
+
+} // Sync
+} // ns3
+
+#endif // SYNC_LEAF_H