ConditionsMap.hh

#ifndef ConditionsMap_h
#define ConditionsMap_h

#include "lcio.h"
#include "EVENT/LCCollection.h"

#include "lccd/IConditionsChangeListener.hh"

#include <map>
#include <typeinfo>
#include <sstream>

namespace lccd {
  
  template <class KEY, class LCCONDOBJECT>
  class ConditionsMap : public lccd::IConditionsChangeListener {

  public:
    
    typedef typename std::map< KEY, LCCONDOBJECT >::iterator MapIter ;

    // PMF: pointer to member function that returns the key
    typedef KEY (LCCONDOBJECT::*PMF)() ;  


    ConditionsMap( PMF pmf ) : _pmf(pmf) {
    }


    virtual ~ConditionsMap() {} 


    const std::map< KEY, LCCONDOBJECT> & map() { return _map ; }
    
    
    LCCONDOBJECT& find( KEY key) {

      MapIter it = _map.find( key ) ;

      if( it == _map.end() ){
        std::stringstream err ;
        err << "ConditionsMap::find: no entry for key: " << key ;
        throw Exception( err.str() ) ;
      }
      else
        return it->second ;
    }


    void conditionsChanged( lcio::LCCollection* col ) {
      
      _map.clear() ;
      
      // add all elements in the collection to the map
      for( int i=0; i< col->getNumberOfElements() ; i++ ){
        
        // this requires that the c'tor exists in LCCONDOBJECT !
        LCCONDOBJECT obj( col->getElementAt( i ) ) ;
        
        
        _map.insert( std::make_pair( (obj.*_pmf)() , obj)  ) ;
        // call member function for key  ^^^^^^^  ,e.g.
        // _map.insert( std::make_pair( obj.getCellID() , obj)  ) ;
      }

//       print( std::cout ) ;
    }

    void print(  std::ostream& os ) {
      
      os << "ConditionsMap"  
//       << std::typeid(keyType).name() << "," 
//       << typeid( typename LCCONDOBJECT ).name() 
         << std::endl ;
      
      //   for( std::map< KEY, LCCONDOBJECT >::iterator it = _map.begin() ;
      for( MapIter it = _map.begin() ;
           it != _map.end() ;
           it++ ){
        
        os << "  key: " <<  it->first  << " - [" << it->second.id() << "]" 
           << " - " << typeid( it->second ).name() 
           << std::endl ;
      }
      
    }
    

  protected:
    
    ConditionsMap() { }
 


    std::map< KEY, LCCONDOBJECT > _map ;
    PMF _pmf ;
};

} ; //end namespace

#endif // ConditionsMap_h

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