add two classes
diff --git a/model/sync-app-data-fetch.h b/model/sync-app-data-fetch.h
new file mode 100644
index 0000000..1bba3a6
--- /dev/null
+++ b/model/sync-app-data-fetch.h
@@ -0,0 +1,54 @@
+/* -*- 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-ccnx-wrapper.h"
+#include <boost/function.hpp>
+#include <boost/shared_ptr.hpp>
+
+namespace Sync {
+
+/**
+ * \ingroup sync
+ * @brief fetch application data, by default it will try to fetch every piece
+ * of data
+ */
+class AppDataFetch
+{
+public:
+ AppDataFetch(boost::function<void (boost::shared_ptr<DataBuffer>)>
+ dataCallback);
+ void setDataCallback(boost::function<void (boost::shared_ptr<DataBuffer>)>
+ dataCallback) {m_dataCallback = dataCallback;}
+ void fetch(string prefix, long startSeq, long endSeq);
+
+private:
+ boost::shared_ptr<CcnxWrapper> ccnxHandle;
+ boost::shared_ptr<boost::function<void (boost::shared_ptr<DataBuffer>)>
+ m_dataCallback;
+};
+
+
+} // Sync
+
+#endif // SYNC_LEAF_H