resultSet.hpp

/*
  ANCH Framework: ANother C++ Hack is a C++ framework based on C++11 standard
  Copyright (C) 2012 Vincent Lachenal

  This file is part of ANCH Framework.

  ANCH Framework is free software: you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  ANCH Framework 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 Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with ANCH Framework.  If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _ANCH_SQL_RESULT_SET_H_
#define _ANCH_SQL_RESULT_SET_H_

#include <string>
#include <vector>
#include <sstream>
#include <map>

#include "sql/sqlException.hpp"

namespace anch {
  namespace sql {

    class ResultSet {

      // Attributes +
    protected:
      std::map<std::string, std::size_t> _fields;
      // Attributes -

      // Constructors +
    public:
      ResultSet();
      // Constructors -

      // Destructor +
    public:
      virtual ~ResultSet();
      // Destructor -

      // Methods +
      template<typename T>
      const T* get(std::size_t idx) throw(SqlException);

      template<typename T>
      bool get(std::size_t idx, T& out) throw(SqlException);

      template<typename T>
      bool get(const std::string field, T& out) throw(SqlException) {
        auto search = _fields.find(field);
        if(search == _fields.end()) {
          std::ostringstream msg;
          msg << "Field " << field << " does not exist in result set. "
            "Available fields are [";
          for(auto iter = _fields.cbegin() ; iter != _fields.cend() ; ++iter) {
            if(iter != _fields.cbegin()) {
              msg << ',';
            }
            msg << iter->first;
          }
          msg << ']';
          throw SqlException(msg.str());
        }
        return get<T>(search->second, out);
      }

      template<typename T>
      const T* get(const std::string field) throw(SqlException) {
        auto search = _fields.find(field);
        if(search == _fields.end()) {
          std::ostringstream msg;
          msg << "Field " << field << " does not exist in result set. "
            "Available fields are [";
          for(auto iter = _fields.cbegin() ; iter != _fields.cend() ; ++iter) {
            if(iter != _fields.cbegin()) {
              msg << ',';
            }
            msg << iter->first;
          }
          msg << ']';
          throw SqlException(msg.str());
        }
        return get<T>(search->second);
      }

      virtual bool next() throw(SqlException) = 0;

    protected:
      virtual bool getValue(std::size_t idx, std::string& out) throw(SqlException) = 0;
      // Methods -

    };

  }
}

#endif // _ANCH_SQL_RESULT_SET_H_