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#ifndef MOZC_CONVERTER_CACHED_CONNECTOR_H_
#define MOZC_CONVERTER_CACHED_CONNECTOR_H_

#include "base/port.h"
#include "converter/connector_interface.h"

namespace mozc {
// The result of GetTransitionCost() is cached with TLS.
// Note that the cache is created as a global variable. If you
// pass two different connectors, the cache variable will be shared.
// Since we can assume that real Connector is a singleton object,
// this restriction will not be a big issue.
class CachedConnector : public ConnectorInterface {
 public:
  // Use cache that defined at other place.
  CachedConnector(ConnectorInterface *connector,
                  bool *cache_initialized,
                  int *cache_key,
                  int *cache_value,
                  int cache_size);
  virtual ~CachedConnector();

  virtual int GetTransitionCost(uint16 rid, uint16 lid) const;
  virtual int GetResolution() const;

  // Clear cache explicitly.
  void ClearCache();

 private:
  void InitializeCache() const;

  ConnectorInterface *connector_;
  // Pointers to the chache.
  // Cache should be created as global variables.
  // For the performance, we are assuming the cache is an array, not vector.
  bool *cache_initialized_;
  int *cache_key_;
  int *cache_value_;
  const int cache_size_;
};
}  // namespace mozc

#endif  // MOZC_CONVERTER_CACHED_CONNECTOR_H_