poco/Util/include/Poco/Util/ConfigurationView.h
2008-01-28 17:30:40 +00:00

104 lines
3.5 KiB
C++

//
// ConfigurationView.h
//
// $Id: //poco/svn/Util/include/Poco/Util/ConfigurationView.h#1 $
//
// Library: Util
// Package: Configuration
// Module: ConfigurationView
//
// Definition of the ConfigurationView class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
//
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
#ifndef Util_ConfigurationView_INCLUDED
#define Util_ConfigurationView_INCLUDED
#include "Poco/Util/Util.h"
#include "Poco/Util/AbstractConfiguration.h"
namespace Poco {
namespace Util {
class Util_API ConfigurationView: public AbstractConfiguration
/// This configuration implements a "view" into a sub-hierarchy
/// of another configuration.
///
/// For example, given a configuration with the following properties:
/// config.value1
/// config.value2
/// config.sub.value1
/// config.sub.value2
/// and a ConfigurationView with the prefix "config", then
/// the above properties will be available via the view as
/// value1
/// value2
/// sub.value1
/// sub.value2
///
/// A ConfigurationView is most useful in combination with a
/// LayeredConfiguration.
///
/// If a property is not found in the view, it is searched in
/// the original configuration. Given the above example configuration,
/// the property named "config.value1" will still be found in the view.
///
/// The main reason for this is that placeholder expansion (${property})
/// still works as expected given a ConfigurationView.
{
public:
ConfigurationView(const std::string& prefix, AbstractConfiguration* pConfig);
/// Creates the ConfigurationView. The ConfigurationView does not take
/// ownership of the passed configuration.
protected:
bool getRaw(const std::string& key, std::string& value) const;
void setRaw(const std::string& key, const std::string& value);
void enumerate(const std::string& key, Keys& range) const;
std::string translateKey(const std::string& key) const;
~ConfigurationView();
private:
ConfigurationView(const ConfigurationView&);
ConfigurationView& operator = (const ConfigurationView&);
std::string _prefix;
AbstractConfiguration* _pConfig;
};
} } // namespace Poco::Util
#endif // Util_ConfigurationView_INCLUDED