//-----------------------------------------------------------------------------
//
// File and Version Information:
// 	$Id: BdbConfigDirectCache.hh,v 1.2 1998/01/19 12:25:25 yury Exp $
//
// Description:
//	Class BdbConfigDirectCache: caches a configuration database 
//      object for repeated access. This class implements direct access 
//      to the database via BdbConfigDatabase::fetch() call.
//
// Environment:
//	Software developed for the BaBar Detector at the SLAC B-Factory.
//
// Author List:
//      Yury Kolomensky                 original author
//
// Copyright Information:
//	Copyright (C) 1998              California Institute of Technology
//
//-----------------------------------------------------------------------------
#ifndef BDBCONFIGDIRECTCACHE_HH
#define BDBCONFIGDIRECTCACHE_HH

//-----------------------
// Base Class Headers --
//-----------------------
#include "BdbConfig/BdbConfigCache.hh"

//-------------------------------
// Collaborating Class Headers --
//-------------------------------
#include "BdbConfig/BdbConfigObject.hh"

#include "rw/cstring.h"

//------------------------------------
// Collaborating Class Declarations --
//------------------------------------
class BdbConfigDatabase;
class BdbConfigKey;

//		---------------------
// 		-- Class Interface --
//		---------------------
class BdbConfigDirectCache : public BdbConfigCache {
public:
  //
  // Constructor: a cache is uniquely defined by the path to the object and 
  // (possibly) a secondary key
  //
  BdbConfigDirectCache(const char* theDatabaseName,
		       const char* theClassName,
		       const char* secondaryKey=0);

  // Destructor
  virtual ~BdbConfigDirectCache( );

  // method to test the cache
  virtual bool isCacheValid(const BdbConfigKey& theKey );

  //  Access the relevant strings
  const char* secondaryKey() const { return _secondaryKey; }

protected:
  // Fetch the object, given the ConfigKey.  
  virtual BdbHandle(BdbConfigObject) fetch( const BdbConfigKey& theKey );

  // Data members
  char*            _secondaryKey;            // secondary key
  BdbConfigDatabase* _database;              // database
  BdbConfigKey     _configKey;               // cache it for convenience
}; 

#endif