patternparser.h

功能非常强的写日志程序

/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * Licensed 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_HELPER_PATTERN_PARSER_H
#define _LOG4CXX_HELPER_PATTERN_PARSER_H

#include <log4cxx/helpers/tchar.h>
#include <log4cxx/helpers/objectptr.h>
#include <log4cxx/helpers/objectimpl.h>
#include <log4cxx/helpers/formattinginfo.h>
#include <log4cxx/helpers/patternconverter.h>

namespace log4cxx
{
	namespace spi
	{
		class LoggingEvent;
		typedef helpers::ObjectPtrT<LoggingEvent> LoggingEventPtr;
	} 

	namespace helpers
	{

		class DateFormat;

	/**
	Most of the work of the PatternLayout class
	is delegated to the PatternParser class.
	
	<p>It is this class that parses conversion patterns and creates
	a chained list of {@link helpers::OptionConverter OptionConverters}.
	*/
		class LOG4CXX_EXPORT PatternParser
		{
		protected:
			int state;
			StringBuffer currentLiteral;
			int patternLength;
			int i;
			PatternConverterPtr head;
			PatternConverterPtr tail;
			FormattingInfo formattingInfo;
			String pattern;
			String timeZone;

		public:
			PatternParser(const String& pattern, const String& timeZone);
			
		private:
			void addToList(PatternConverterPtr& pc);
			
		protected:
			String extractOption();
			
			/**
			The option is expected to be in decimal and positive. In case of
			error, zero is returned.  */
			int extractPrecisionOption();
			
		public:
			PatternConverterPtr parse();
			
		protected:
			void finalizeConverter(TCHAR c);

			void addConverter(PatternConverterPtr& pc);

		// ---------------------------------------------------------------------
		//                      PatternConverters
		// ---------------------------------------------------------------------
		private:
			class LOG4CXX_EXPORT BasicPatternConverter : public PatternConverter
			{
			private:
				int type;
			public:
				BasicPatternConverter(const FormattingInfo& formattingInfo, int type);
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};

			class LOG4CXX_EXPORT LiteralPatternConverter : public PatternConverter
			{
			private:
				String literal;

			public:
				LiteralPatternConverter(const String& value);
				virtual void format(StringBuffer& sbuf, 
					const spi::LoggingEventPtr& e) const;
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};

			class LOG4CXX_EXPORT DatePatternConverter : public PatternConverter
			{
			private:
				DateFormat * df;

			public:
				DatePatternConverter(const FormattingInfo& formattingInfo, 
					DateFormat * df);
				~DatePatternConverter();
				
			public:
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};

			class LOG4CXX_EXPORT MDCPatternConverter : public PatternConverter
			{
			private:
				String key;
			
			public:
				MDCPatternConverter(const FormattingInfo& formattingInfo,
					const String& key);
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};

			class LOG4CXX_EXPORT LocationPatternConverter : public PatternConverter
			{
			private:
				int type;
			
			public:
				LocationPatternConverter(const FormattingInfo& formattingInfo, int type);
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};

			class LOG4CXX_EXPORT CategoryPatternConverter : public PatternConverter
			{
			private:
				int precision;
			
			public:
				CategoryPatternConverter(const FormattingInfo& formattingInfo, 
					int precision);
				virtual void convert(ostream& sbuf, 
					const spi::LoggingEventPtr& event) const;
			};
		}; // class PatternParser
	}  // namespace helpers
}; // namespace log4cxx

#endif //_LOG4CXX_HELPER_PATTERN_PARSER_H