text: ////////////////////////////////////////////////////////////////////////////////
  /// DISCLAIMER
  ///
  /// Copyright 2014-2020 ArangoDB GmbH, Cologne, Germany
  /// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
  ///
  /// 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.
  ///
  /// Copyright holder is ArangoDB GmbH, Cologne, Germany
  ///
  /// @author Jan Steemann
  ////////////////////////////////////////////////////////////////////////////////
  
  #ifndef ARANGOD_UTILS_FLUSH_THREAD_H
  #define ARANGOD_UTILS_FLUSH_THREAD_H 1
  
  #include "Basics/Common.h"
  #include "Basics/ConditionVariable.h"
  #include "Basics/Thread.h"
  
  namespace arangodb {
  class FlushFeature;
  
  class FlushThread final : public Thread {
   private:
    FlushThread(FlushThread const&) = delete;
    FlushThread& operator=(FlushThread const&) = delete;
  
   public:
    /// flush interval in microseconds
    explicit FlushThread(FlushFeature& feature, uint64_t flushInterval);
    ~FlushThread() { shutdown(); }
  
   public:
    void beginShutdown() override;
  
    /// @brief wake up the flush thread
    void wakeup();
  
   private:
    void run() override;
  
   private:
    /// @brief condition variable for the thread
    basics::ConditionVariable _condition;
  
    /// @brief reference to the owning feature
    FlushFeature& _feature;
  
    /// @brief wait interval for the flusher thread when idle (in microseconds)
    uint64_t const _flushInterval;
  };
  
  }  // namespace arangodb
  
  #endif
  