src/main/include/log4cxx/patternlayout.h - logging-log4cxx - Git at Google

 /*
  * 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_PATTERN_LAYOUT_H
 #define _LOG4CXX_PATTERN_LAYOUT_H

 #if defined(_MSC_VER)
 #pragma warning ( push )
 #pragma warning ( disable: 4231 4251 4275 4786 )
 #endif


 #include <log4cxx/layout.h>
 #include <log4cxx/pattern/loggingeventpatternconverter.h>
 #include <log4cxx/pattern/formattinginfo.h>
 #include <log4cxx/pattern/patternparser.h>

 namespace log4cxx
 {

         /**

         A flexible layout configurable with pattern string.

         <p>The goal of this class is to #format a {@link
         spi::LoggingEvent LoggingEvent} and return the results as a string.
         The results depend on the <em>conversion pattern</em>.

         <p>The conversion pattern is closely related to the conversion
         pattern of the printf function in C. A conversion pattern is
         composed of literal text and format control expressions called
         <em>conversion specifiers</em>.

         <p><i>You are free to insert any literal text within the conversion
         pattern.</i>

         <p>Each conversion specifier starts with a percent sign (\%) and is
         followed by optional <em>format modifiers</em> and a <em>conversion
         character</em>. The conversion character specifies the type of
         data, e.g. logger, level, date, thread name. The format
         modifiers control such things as field width, padding, left and
         right justification. The following is a simple example.

         <p>Let the conversion pattern be <b>"\%-5p [\%t]: \%m\%n"</b> and assume
         that the log4cxx environment was set to use a PatternLayout. Then the
         statements
         <pre>
         LoggerPtr root = Logger::getRoot();
         root->debug("Message 1");
         root->warn("Message 2");
         </pre>
         would yield the output
         <pre>
         DEBUG [main]: Message 1
         WARN  [main]: Message 2
         </pre>

         <p>Note that there is no explicit separator between text and
         conversion specifiers. The pattern parser knows when it has reached
         the end of a conversion specifier when it reads a conversion
         character. In the example above the conversion specifier
         <b>\%-5p</b> means the level of the logging event should be left
         justified to a width of five characters.

         The recognized conversion characters are

         <p>
         <table border="1" CELLPADDING="8">
         <tr>
         <td align=center><b>Conversion Character</b></td>
         <td align=center><b>Effect</b></td>
         </tr>

         <tr>
         <td align=center><b>c</b></td>

         <td>Used to output the logger of the logging event. The
         logger conversion specifier can be optionally followed by
         <em>precision specifier</em>, that is a decimal constant in
         brackets.

         <p>If a precision specifier is given, then only the corresponding
         number of right most components of the logger name will be
         printed. By default the logger name is printed in full.

         <p>For example, for the logger name "a.b.c" the pattern
         <b>\%c{2}</b> will output "b.c".

         </td>
         </tr>

    <tr> <td align=center><b>d</b></td> <td>Used to output the date of
          the logging event. The date conversion specifier may be
          followed by a set of braces containing a
          date and time pattern string compatible with java.text.SimpleDateFormat,
          <em>ABSOLUTE</em>, <em>DATE</em> or <em>ISO8601</em>.
          For example, <b>%d{HH:mm:ss,SSS}</b>,
          <b>%d{dd&nbsp;MMM&nbsp;yyyy&nbsp;HH:mm:ss,SSS}</b> or
          <b>%d{DATE}</b>.  If no date format specifier is given then
          ISO8601 format is assumed.
      </td>
    </tr>

         <tr>
         <td align=center><b>F</b></td>

         <td>Used to output the file name where the logging request was
         issued.

         </tr>

         <tr>
         <td align=center><b>l</b></td>

         <td>Used to output location information of the caller which generated
         the logging event.

         </td>
         </tr>

         <tr>
         <td align=center><b>L</b></td>

         <td>Used to output the line number from where the logging request
         was issued.
         </tr>


         <tr>
         <td align=center><b>m</b></td>
         <td>Used to output the application supplied message associated with
         the logging event.</td>
         </tr>

         <tr>
         <td align=center><b>n</b></td>

         <td>Outputs the platform dependent line separator character or
         characters.

         <p>This conversion character offers practically the same
         performance as using non-portable line separator strings such as
         "\n", or "\r\n". Thus, it is the preferred way of specifying a
         line separator.


         </tr>

         <tr>
         <td align=center><b>p</b></td>
         <td>Used to output the level of the logging event.</td>
         </tr>

         <tr>

         <td align=center><b>r</b></td>

         <td>Used to output the number of milliseconds elapsed since the start
         of the application until the creation of the logging event.</td>
         </tr>


         <tr>
         <td align=center><b>t</b></td>

         <td>Used to output the name of the thread that generated the
         logging event.</td>

         </tr>

         <tr>

         <td align=center><b>x</b></td>

         <td>Used to output the NDC (nested diagnostic context) associated
         with the thread that generated the logging event.
         </td>
         </tr>


         <tr>
         <td align=center><b>X</b></td>

         <td>

         <p>Used to output the MDC (mapped diagnostic context) associated
         with the thread that generated the logging event. The <b>X</b>
         conversion character <em>must</em> be followed by the key for the
         map placed between braces, as in <b>\%X{clientNumber}</b> where
         <code>clientNumber</code> is the key. The value in the MDC
         corresponding to the key will be output.</p>

         <p>See MDC class for more details.
         </p>

         </td>
         </tr>

         <tr>

         <td align=center><b>\%</b></td>

         <td>The sequence \%\% outputs a single percent sign.
         </td>
         </tr>

         </table>

         <p>By default the relevant information is output as is. However,
         with the aid of format modifiers it is possible to change the
         minimum field width, the maximum field width and justification.

         <p>The optional format modifier is placed between the percent sign
         and the conversion character.

         <p>The first optional format modifier is the <em>left justification
         flag</em> which is just the minus (-) character. Then comes the
         optional <em>minimum field width</em> modifier. This is a decimal
         constant that represents the minimum number of characters to
         output. If the data item requires fewer characters, it is padded on
         either the left or the right until the minimum width is
         reached. The default is to pad on the left (right justify) but you
         can specify right padding with the left justification flag. The
         padding character is space. If the data item is larger than the
         minimum field width, the field is expanded to accommodate the
         data. The value is never truncated.

         <p>This behavior can be changed using the <em>maximum field
         width</em> modifier which is designated by a period followed by a
         decimal constant. If the data item is longer than the maximum
         field, then the extra characters are removed from the
         <em>beginning</em> of the data item and not from the end. For
         example, it the maximum field width is eight and the data item is
         ten characters long, then the first two characters of the data item
         are dropped. This behavior deviates from the printf function in C
         where truncation is done from the end.

         <p>Below are various format modifier examples for the logger
         conversion specifier.

         <p>
         <TABLE BORDER=1 CELLPADDING=8>
         <tr>
         <td align=center><b>Format modifier</b></td>
         <td align=center><b>left justify</b></td>
         <td align=center><b>minimum width</b></td>
         <td align=center><b>maximum width</b></td>
         <td align=center><b>comment</b></td>
         </tr>

         <tr>
         <td align=center>\%20c</td>
         <td align=center>false</td>
         <td align=center>20</td>
         <td align=center>none</td>

         <td>Left pad with spaces if the logger name is less than 20
         characters long.

         <tr> <td align=center>\%-20c</td> <td align=center>true</td> <td
         align=center>20</td> <td align=center>none</td> <td>Right pad with
         spaces if the logger name is less than 20 characters long.

         <tr>
         <td align=center>\%.30c</td>
         <td align=center>NA</td>
         <td align=center>none</td>
         <td align=center>30</td>

         <td>Truncate from the beginning if the logger name is longer than 30
         characters.

         <tr>
         <td align=center>\%20.30c</td>
         <td align=center>false</td>
         <td align=center>20</td>
         <td align=center>30</td>

         <td>Left pad with spaces if the logger name is shorter than 20
         characters. However, if logger name is longer than 30 characters,
         then truncate from the beginning.

         <tr>
         <td align=center>\%-20.30c</td>
         <td align=center>true</td>
         <td align=center>20</td>
         <td align=center>30</td>

         <td>Right pad with spaces if the logger name is shorter than 20
         characters. However, if logger name is longer than 30 characters,
         then truncate from the beginning.

         </table>

         <p>Below are some examples of conversion patterns.

         <p><b>\%r [\%t] \%-5p \%c \%x - \%m\n</b>
         <p>This is essentially the TTCC layout.

         <p><b>\%-6r [\%15.15t] \%-5p \%30.30c \%x - \%m\n</b>

         <p>Similar to the TTCC layout except that the relative time is
         right padded if less than 6 digits, thread name is right padded if
         less than 15 characters and truncated if longer and the logger
         name is left padded if shorter than 30 characters and truncated if
         longer.

         <p>The above text is largely inspired from Peter A. Darnell and
         Philip E. Margolis' highly recommended book "C -- a Software
         Engineering Approach", ISBN 0-387-97389-3.
         */
         class LOG4CXX_EXPORT PatternLayout : public Layout
         {
                  /**
                   * Conversion pattern.
                   */
                 LogString conversionPattern;

                 /**
                  * Pattern converters.
                  */
                 LOG4CXX_LIST_DEF(LoggingEventPatternConverterList, log4cxx::pattern::LoggingEventPatternConverterPtr);
                 LoggingEventPatternConverterList patternConverters;

                /**
                 * Field widths and alignment corresponding to pattern converters.
                 */
                 LOG4CXX_LIST_DEF(FormattingInfoList, log4cxx::pattern::FormattingInfoPtr);
                 FormattingInfoList patternFields;


         public:
                 DECLARE_LOG4CXX_OBJECT(PatternLayout)
                 BEGIN_LOG4CXX_CAST_MAP()
                         LOG4CXX_CAST_ENTRY(PatternLayout)
                         LOG4CXX_CAST_ENTRY_CHAIN(Layout)
                 END_LOG4CXX_CAST_MAP()

                 /**
                 Does nothing
                 */
                 PatternLayout();

                 /**
                 Constructs a PatternLayout using the supplied conversion pattern.
                 */
                 PatternLayout(const LogString& pattern);

                 /**
                 Set the <b>ConversionPattern</b> option. This is the string which
                 controls formatting and consists of a mix of literal content and
                 conversion specifiers.
                 */
                 void setConversionPattern(const LogString& conversionPattern);

                 /**
                 Returns the value of the <b>ConversionPattern</b> option.
                 */
                 inline LogString getConversionPattern() const
                         { return conversionPattern; }

                 /**
                 Call createPatternParser
                 */
                 virtual void activateOptions(log4cxx::helpers::Pool& p);

                 virtual void setOption(const LogString& option, const LogString& value);

                 /**
                 The PatternLayout does not handle the throwable contained within
                 {@link spi::LoggingEvent LoggingEvents}. Thus, it returns
                 <code>true</code>.
                 */
                 virtual bool ignoresThrowable() const
                         { return true; }

                 /**
                 Produces a formatted string as specified by the conversion pattern.
                 */
                 virtual void format(LogString& output,
                      const spi::LoggingEventPtr& event, log4cxx::helpers::Pool& pool) const;

         protected:
                 virtual log4cxx::pattern::PatternMap getFormatSpecifiers();
         };
       LOG4CXX_PTR_DEF(PatternLayout);
 }  // namespace log4cxx

 #if defined(_MSC_VER)
 #pragma warning ( pop )
 #endif


 #endif //_LOG4CXX_PATTERN_LAYOUT_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_PATTERN_LAYOUT_H
	#define _LOG4CXX_PATTERN_LAYOUT_H

	#if defined(_MSC_VER)
	#pragma warning ( push )
	#pragma warning ( disable: 4231 4251 4275 4786 )
	#endif



	#include <log4cxx/layout.h>
	#include <log4cxx/pattern/loggingeventpatternconverter.h>
	#include <log4cxx/pattern/formattinginfo.h>
	#include <log4cxx/pattern/patternparser.h>

	namespace log4cxx
	{

	/**

	A flexible layout configurable with pattern string.

	<p>The goal of this class is to #format a {@link
	spi::LoggingEvent LoggingEvent} and return the results as a string.
	The results depend on the <em>conversion pattern</em>.

	<p>The conversion pattern is closely related to the conversion
	pattern of the printf function in C. A conversion pattern is
	composed of literal text and format control expressions called
	<em>conversion specifiers</em>.

	<p><i>You are free to insert any literal text within the conversion
	pattern.</i>

	<p>Each conversion specifier starts with a percent sign (\%) and is
	followed by optional <em>format modifiers</em> and a <em>conversion
	character</em>. The conversion character specifies the type of
	data, e.g. logger, level, date, thread name. The format
	modifiers control such things as field width, padding, left and
	right justification. The following is a simple example.

	<p>Let the conversion pattern be <b>"\%-5p [\%t]: \%m\%n"</b> and assume
	that the log4cxx environment was set to use a PatternLayout. Then the
	statements
	<pre>
	LoggerPtr root = Logger::getRoot();
	root->debug("Message 1");
	root->warn("Message 2");
	</pre>
	would yield the output
	<pre>
	DEBUG [main]: Message 1
	WARN [main]: Message 2
	</pre>

	<p>Note that there is no explicit separator between text and
	conversion specifiers. The pattern parser knows when it has reached
	the end of a conversion specifier when it reads a conversion
	character. In the example above the conversion specifier
	<b>\%-5p</b> means the level of the logging event should be left
	justified to a width of five characters.

	The recognized conversion characters are

	<p>
	<table border="1" CELLPADDING="8">
	<tr>
	<td align=center><b>Conversion Character</b></td>
	<td align=center><b>Effect</b></td>
	</tr>

	<tr>
	<td align=center><b>c</b></td>

	<td>Used to output the logger of the logging event. The
	logger conversion specifier can be optionally followed by
	<em>precision specifier</em>, that is a decimal constant in
	brackets.

	<p>If a precision specifier is given, then only the corresponding
	number of right most components of the logger name will be
	printed. By default the logger name is printed in full.

	<p>For example, for the logger name "a.b.c" the pattern
	<b>\%c{2}</b> will output "b.c".

	</td>
	</tr>

	<tr> <td align=center><b>d</b></td> <td>Used to output the date of
	the logging event. The date conversion specifier may be
	followed by a set of braces containing a
	date and time pattern string compatible with java.text.SimpleDateFormat,
	<em>ABSOLUTE</em>, <em>DATE</em> or <em>ISO8601</em>.
	For example, <b>%d{HH:mm:ss,SSS}</b>,
	<b>%d{dd MMM yyyy HH:mm:ss,SSS}</b> or
	<b>%d{DATE}</b>. If no date format specifier is given then
	ISO8601 format is assumed.
	</td>
	</tr>

	<tr>
	<td align=center><b>F</b></td>

	<td>Used to output the file name where the logging request was
	issued.

	</tr>

	<tr>
	<td align=center><b>l</b></td>

	<td>Used to output location information of the caller which generated
	the logging event.

	</td>
	</tr>

	<tr>
	<td align=center><b>L</b></td>

	<td>Used to output the line number from where the logging request
	was issued.
	</tr>


	<tr>
	<td align=center><b>m</b></td>
	<td>Used to output the application supplied message associated with
	the logging event.</td>
	</tr>

	<tr>
	<td align=center><b>n</b></td>

	<td>Outputs the platform dependent line separator character or
	characters.

	<p>This conversion character offers practically the same
	performance as using non-portable line separator strings such as
	"\n", or "\r\n". Thus, it is the preferred way of specifying a
	line separator.


	</tr>

	<tr>
	<td align=center><b>p</b></td>
	<td>Used to output the level of the logging event.</td>
	</tr>

	<tr>

	<td align=center><b>r</b></td>

	<td>Used to output the number of milliseconds elapsed since the start
	of the application until the creation of the logging event.</td>
	</tr>


	<tr>
	<td align=center><b>t</b></td>

	<td>Used to output the name of the thread that generated the
	logging event.</td>

	</tr>

	<tr>

	<td align=center><b>x</b></td>

	<td>Used to output the NDC (nested diagnostic context) associated
	with the thread that generated the logging event.
	</td>
	</tr>


	<tr>
	<td align=center><b>X</b></td>

	<td>

	<p>Used to output the MDC (mapped diagnostic context) associated
	with the thread that generated the logging event. The <b>X</b>
	conversion character <em>must</em> be followed by the key for the
	map placed between braces, as in <b>\%X{clientNumber}</b> where
	<code>clientNumber</code> is the key. The value in the MDC
	corresponding to the key will be output.</p>

	<p>See MDC class for more details.
	</p>

	</td>
	</tr>

	<tr>

	<td align=center><b>\%</b></td>

	<td>The sequence \%\% outputs a single percent sign.
	</td>
	</tr>

	</table>

	<p>By default the relevant information is output as is. However,
	with the aid of format modifiers it is possible to change the
	minimum field width, the maximum field width and justification.

	<p>The optional format modifier is placed between the percent sign
	and the conversion character.

	<p>The first optional format modifier is the <em>left justification
	flag</em> which is just the minus (-) character. Then comes the
	optional <em>minimum field width</em> modifier. This is a decimal
	constant that represents the minimum number of characters to
	output. If the data item requires fewer characters, it is padded on
	either the left or the right until the minimum width is
	reached. The default is to pad on the left (right justify) but you
	can specify right padding with the left justification flag. The
	padding character is space. If the data item is larger than the
	minimum field width, the field is expanded to accommodate the
	data. The value is never truncated.

	<p>This behavior can be changed using the <em>maximum field
	width</em> modifier which is designated by a period followed by a
	decimal constant. If the data item is longer than the maximum
	field, then the extra characters are removed from the
	<em>beginning</em> of the data item and not from the end. For
	example, it the maximum field width is eight and the data item is
	ten characters long, then the first two characters of the data item
	are dropped. This behavior deviates from the printf function in C
	where truncation is done from the end.

	<p>Below are various format modifier examples for the logger
	conversion specifier.

	<p>
	<TABLE BORDER=1 CELLPADDING=8>
	<tr>
	<td align=center><b>Format modifier</b></td>
	<td align=center><b>left justify</b></td>
	<td align=center><b>minimum width</b></td>
	<td align=center><b>maximum width</b></td>
	<td align=center><b>comment</b></td>
	</tr>

	<tr>
	<td align=center>\%20c</td>
	<td align=center>false</td>
	<td align=center>20</td>
	<td align=center>none</td>

	<td>Left pad with spaces if the logger name is less than 20
	characters long.

	<tr> <td align=center>\%-20c</td> <td align=center>true</td> <td
	align=center>20</td> <td align=center>none</td> <td>Right pad with
	spaces if the logger name is less than 20 characters long.

	<tr>
	<td align=center>\%.30c</td>
	<td align=center>NA</td>
	<td align=center>none</td>
	<td align=center>30</td>

	<td>Truncate from the beginning if the logger name is longer than 30
	characters.

	<tr>
	<td align=center>\%20.30c</td>
	<td align=center>false</td>
	<td align=center>20</td>
	<td align=center>30</td>

	<td>Left pad with spaces if the logger name is shorter than 20
	characters. However, if logger name is longer than 30 characters,
	then truncate from the beginning.

	<tr>
	<td align=center>\%-20.30c</td>
	<td align=center>true</td>
	<td align=center>20</td>
	<td align=center>30</td>

	<td>Right pad with spaces if the logger name is shorter than 20
	characters. However, if logger name is longer than 30 characters,
	then truncate from the beginning.

	</table>

	<p>Below are some examples of conversion patterns.

	<p><b>\%r [\%t] \%-5p \%c \%x - \%m\n</b>
	<p>This is essentially the TTCC layout.

	<p><b>\%-6r [\%15.15t] \%-5p \%30.30c \%x - \%m\n</b>

	<p>Similar to the TTCC layout except that the relative time is
	right padded if less than 6 digits, thread name is right padded if
	less than 15 characters and truncated if longer and the logger
	name is left padded if shorter than 30 characters and truncated if
	longer.

	<p>The above text is largely inspired from Peter A. Darnell and
	Philip E. Margolis' highly recommended book "C -- a Software
	Engineering Approach", ISBN 0-387-97389-3.
	*/
	class LOG4CXX_EXPORT PatternLayout : public Layout
	{
	/**
	* Conversion pattern.
	*/
	LogString conversionPattern;

	/**
	* Pattern converters.
	*/
	LOG4CXX_LIST_DEF(LoggingEventPatternConverterList, log4cxx::pattern::LoggingEventPatternConverterPtr);
	LoggingEventPatternConverterList patternConverters;

	/**
	* Field widths and alignment corresponding to pattern converters.
	*/
	LOG4CXX_LIST_DEF(FormattingInfoList, log4cxx::pattern::FormattingInfoPtr);
	FormattingInfoList patternFields;


	public:
	DECLARE_LOG4CXX_OBJECT(PatternLayout)
	BEGIN_LOG4CXX_CAST_MAP()
	LOG4CXX_CAST_ENTRY(PatternLayout)
	LOG4CXX_CAST_ENTRY_CHAIN(Layout)
	END_LOG4CXX_CAST_MAP()

	/**
	Does nothing
	*/
	PatternLayout();

	/**
	Constructs a PatternLayout using the supplied conversion pattern.
	*/
	PatternLayout(const LogString& pattern);

	/**
	Set the <b>ConversionPattern</b> option. This is the string which
	controls formatting and consists of a mix of literal content and
	conversion specifiers.
	*/
	void setConversionPattern(const LogString& conversionPattern);

	/**
	Returns the value of the <b>ConversionPattern</b> option.
	*/
	inline LogString getConversionPattern() const
	{ return conversionPattern; }

	/**
	Call createPatternParser
	*/
	virtual void activateOptions(log4cxx::helpers::Pool& p);

	virtual void setOption(const LogString& option, const LogString& value);

	/**
	The PatternLayout does not handle the throwable contained within
	{@link spi::LoggingEvent LoggingEvents}. Thus, it returns
	<code>true</code>.
	*/
	virtual bool ignoresThrowable() const
	{ return true; }

	/**
	Produces a formatted string as specified by the conversion pattern.
	*/
	virtual void format(LogString& output,
	const spi::LoggingEventPtr& event, log4cxx::helpers::Pool& pool) const;

	protected:
	virtual log4cxx::pattern::PatternMap getFormatSpecifiers();
	};
	LOG4CXX_PTR_DEF(PatternLayout);
	} // namespace log4cxx

	#if defined(_MSC_VER)
	#pragma warning ( pop )
	#endif


	#endif //_LOG4CXX_PATTERN_LAYOUT_H