helper: StrategyChoiceHelper
diff --git a/helper/ndn-strategy-choice-helper.hpp b/helper/ndn-strategy-choice-helper.hpp
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+++ b/helper/ndn-strategy-choice-helper.hpp
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+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2011-2015  Regents of the University of California.
+ *
+ * This file is part of ndnSIM. See AUTHORS for complete list of ndnSIM authors and
+ * contributors.
+ *
+ * ndnSIM is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * ndnSIM 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
+ * ndnSIM, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#ifndef NDN_STRATEGY_CHOICE_HELPER_H
+#define NDN_STRATEGY_CHOICE_HELPER_H
+
+#include "ns3/ndnSIM/model/ndn-common.hpp"
+
+#include "ns3/node.h"
+#include "ns3/ptr.h"
+#include "ns3/node-container.h"
+
+#include "ns3/ndnSIM/model/ndn-l3-protocol.hpp"
+#include "ns3/ndnSIM/NFD/daemon/mgmt/strategy-choice-manager.hpp"
+#include "ns3/ndnSIM/NFD/daemon/fw/available-strategies.hpp"
+
+namespace ndn {
+namespace nfd {
+class ControlParameters;
+} // namespace nfd
+} // namespace ndn
+
+namespace nfd {
+namespace fw {
+class Strategy;
+} // namespace fw
+} // namespace nfd
+
+
+namespace ns3 {
+namespace ndn {
+
+using ::ndn::nfd::ControlParameters;
+
+class StrategyChoiceHelper {
+public:
+  static void
+  Install(const NodeContainer& c, const Name& namePrefix, const Name& strategy);
+
+  static void
+  Install(Ptr<Node> node, const Name& namePrefix, const Name& strategy);
+
+  static void
+  InstallAll(const Name& namePrefix, const Name& strategy);
+
+  template<class Strategy>
+  static void
+  Install(Ptr<Node> node, const Name& namePrefix);
+
+  template<class Strategy>
+  static void
+  Install(const NodeContainer& c, const Name& namePrefix);
+
+  template<class Strategy>
+  static void
+  InstallAll(const Name& namePrefix);
+
+private:
+  static void
+  sendCommand(const ControlParameters& parameters, Ptr<Node> node);
+};
+
+template<class Strategy>
+inline void
+StrategyChoiceHelper::Install(Ptr<Node> node, const Name& namePrefix)
+{
+  Ptr<L3Protocol> l3Protocol = node->GetObject<L3Protocol>();
+  NS_ASSERT(l3Protocol != nullptr);
+  NS_ASSERT(l3Protocol->getForwarder() != nullptr);
+
+  nfd::Forwarder& forwarder = *l3Protocol->getForwarder();
+  nfd::StrategyChoice& strategyChoice = forwarder.getStrategyChoice();
+
+  if (!strategyChoice.hasStrategy(Strategy::STRATEGY_NAME)) {
+    strategyChoice.install(make_shared<Strategy>(ref(forwarder)));
+  }
+
+  Install(node, namePrefix, Strategy::STRATEGY_NAME);
+}
+
+template<class Strategy>
+inline void
+StrategyChoiceHelper::Install(const NodeContainer& c, const Name& namePrefix)
+{
+  for (NodeContainer::Iterator i = c.Begin(); i != c.End(); ++i) {
+    Install<Strategy>(*i, namePrefix);
+  }
+}
+
+template<class Strategy>
+inline void
+StrategyChoiceHelper::InstallAll(const Name& namePrefix)
+{
+  Install<Strategy>(NodeContainer::GetGlobal(), namePrefix);
+}
+
+} // namespace ndn
+} // namespace ns3
+
+#endif // NDN_STRATEGY_CHOICE_HELPER_H