src/main/include/log4cxx/varia/fallbackerrorhandler.h

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _LOG4CXX_VARIA_FALLBACK_ERROR_HANDLER_H
#define _LOG4CXX_VARIA_FALLBACK_ERROR_HANDLER_H

#include <log4cxx/spi/errorhandler.h>
#include <log4cxx/helpers/objectimpl.h>
#include <log4cxx/appender.h>
#include <log4cxx/logger.h>
#include <vector>

namespace log4cxx
{
namespace varia
{
/**
The <code>FallbackErrorHandler</code> implements the ErrorHandler
interface such that a secondary appender may be specified.  This
secondary appender takes over if the primary appender fails for
whatever reason.

<p>The error message is printed on <code>System.err</code>, and
logged in the new secondary appender.
*/
class LOG4CXX_EXPORT FallbackErrorHandler :
	public virtual spi::ErrorHandler,
	public virtual helpers::ObjectImpl
{
	private:
		AppenderPtr backup;
		AppenderPtr primary;
		std::vector<LoggerPtr> loggers;

	public:
		DECLARE_LOG4CXX_OBJECT(FallbackErrorHandler)
		BEGIN_LOG4CXX_CAST_MAP()
		LOG4CXX_CAST_ENTRY(FallbackErrorHandler)
		LOG4CXX_CAST_ENTRY_CHAIN(spi::ErrorHandler)
		END_LOG4CXX_CAST_MAP()

		FallbackErrorHandler();
		void addRef() const;
		void releaseRef() const;


		/**
		<em>Adds</em> the logger passed as parameter to the list of
		loggers that we need to search for in case of appender failure.
		*/
		void setLogger(const LoggerPtr& logger);


		/**
		No options to activate.
		*/
		void activateOptions(log4cxx::helpers::Pool& p);
		void setOption(const LogString& option, const LogString& value);


		/**
		Prints the message and the stack trace of the exception on
		<code>System.err</code>.
		*/
		void error(const LogString& message, const std::exception& e,
			int errorCode) const;

		/**
		Prints the message and the stack trace of the exception on
		<code>System.err</code>.
		*/
		void error(const LogString& message, const std::exception& e,
			int errorCode, const spi::LoggingEventPtr& event) const;


		/**
		Print a the error message passed as parameter on
		<code>System.err</code>.
		*/
		void error(const LogString& /* message */) const {}

		/**
		Return the backup appender.
		*/
		const AppenderPtr& getBackupAppender() const
		{
			return backup;
		}

		/**
		The appender to which this error handler is attached.
		*/
		void setAppender(const AppenderPtr& primary);

		/**
		Set the backup appender.
		*/
		void setBackupAppender(const AppenderPtr& backup);
};
LOG4CXX_PTR_DEF(FallbackErrorHandler);

}  // namespace varia
} // namespace log4cxx

#endif //_LOG4CXX_VARIA_FALLBACK_ERROR_HANDLER_H