Package org.apache.logging.log4j.core.pattern

Class PatternParser

java.lang.Object

org.apache.logging.log4j.core.pattern.PatternParser

public final class PatternParser
extends java.lang.Object

Most of the work of the PatternLayout class is delegated to the PatternParser class.

It is this class that parses conversion patterns and creates a chained list of PatternConverters.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	PatternParser.ParserState	The states the parser can be in while parsing the pattern.

Field Summary

Fields

Modifier and Type	Field	Description
private static int	BUF_SIZE
private Configuration	config
private java.util.Map<java.lang.String,java.lang.Class<PatternConverter>>	converterRules
private static int	DECIMAL
(package private) static java.lang.String	DISABLE_ANSI
private static char	ESCAPE_CHAR	Escape character for format specifier.
private static Logger	LOGGER
(package private) static java.lang.String	NO_CONSOLE_NO_ANSI

Constructor Summary

Constructors

Constructor	Description
PatternParser(java.lang.String converterKey)	Constructor.
PatternParser(Configuration config, java.lang.String converterKey, java.lang.Class<?> expected)	Constructor.
PatternParser(Configuration config, java.lang.String converterKey, java.lang.Class<?> expectedClass, java.lang.Class<?> filterClass)	Constructor.

Method Summary

Modifier and Type	Method	Description
private static boolean	areValidNewInstanceParameters(java.lang.Class<?>[] parameterTypes)	LOG4J2-2564: Returns true if all method parameters are valid for injection.
private PatternConverter	createConverter(java.lang.String converterId, java.lang.StringBuilder currentLiteral, java.util.Map<java.lang.String,java.lang.Class<PatternConverter>> rules, java.util.List<java.lang.String> options, boolean disableAnsi, boolean noConsoleNoAnsi)	Creates a new PatternConverter.
private static int	extractConverter(char lastChar, java.lang.String pattern, int start, java.lang.StringBuilder convBuf, java.lang.StringBuilder currentLiteral)	Extracts the converter identifier found at the given start position.
private static int	extractOptions(java.lang.String pattern, int start, java.util.List<java.lang.String> options)	Extract options.
private int	finalizeConverter(char c, java.lang.String pattern, int start, java.lang.StringBuilder currentLiteral, FormattingInfo formattingInfo, java.util.Map<java.lang.String,java.lang.Class<PatternConverter>> rules, java.util.List<PatternConverter> patternConverters, java.util.List<FormattingInfo> formattingInfos, boolean disableAnsi, boolean noConsoleNoAnsi, boolean convertBackslashes)	Processes a format specifier sequence.
private LogEventPatternConverter	literalPattern(java.lang.String literal, boolean convertBackslashes)
java.util.List<PatternFormatter>	parse(java.lang.String pattern)
java.util.List<PatternFormatter>	parse(java.lang.String pattern, boolean alwaysWriteExceptions, boolean noConsoleNoAnsi)
java.util.List<PatternFormatter>	parse(java.lang.String pattern, boolean alwaysWriteExceptions, boolean disableAnsi, boolean noConsoleNoAnsi)
void	parse(java.lang.String pattern, java.util.List<PatternConverter> patternConverters, java.util.List<FormattingInfo> formattingInfos, boolean noConsoleNoAnsi, boolean convertBackslashes)	Parse a format specifier.
void	parse(java.lang.String pattern, java.util.List<PatternConverter> patternConverters, java.util.List<FormattingInfo> formattingInfos, boolean disableAnsi, boolean noConsoleNoAnsi, boolean convertBackslashes)	Parse a format specifier.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DISABLE_ANSI

static final java.lang.String DISABLE_ANSI

See Also:

Constant Field Values

NO_CONSOLE_NO_ANSI

static final java.lang.String NO_CONSOLE_NO_ANSI

See Also:

Constant Field Values

ESCAPE_CHAR

private static final char ESCAPE_CHAR

Escape character for format specifier.

See Also:

Constant Field Values

LOGGER

private static final Logger LOGGER

BUF_SIZE

private static final int BUF_SIZE

See Also:

Constant Field Values

DECIMAL

private static final int DECIMAL

See Also:

Constant Field Values

config

private final Configuration config

converterRules

private final java.util.Map<java.lang.String,java.lang.Class<PatternConverter>> converterRules

Constructor Detail

PatternParser

public PatternParser(java.lang.String converterKey)

Constructor.

Parameters:

converterKey - The type of converters that will be used.

PatternParser

public PatternParser(Configuration config,
                     java.lang.String converterKey,
                     java.lang.Class<?> expected)

Constructor.

Parameters:

config - The current Configuration or null.

converterKey - The key to lookup the converters.

expected - The expected base Class of each Converter or null.

PatternParser

public PatternParser(Configuration config,
                     java.lang.String converterKey,
                     java.lang.Class<?> expectedClass,
                     java.lang.Class<?> filterClass)

Constructor.

Parameters:

config - The current Configuration or null.

converterKey - The key to lookup the converters.

expectedClass - The expected base Class of each Converter or null.

filterClass - Filter the returned plugins after calling the plugin manager, can be null.

Method Detail

parse

public java.util.List<PatternFormatter> parse(java.lang.String pattern)

parse

public java.util.List<PatternFormatter> parse(java.lang.String pattern,
                                              boolean alwaysWriteExceptions,
                                              boolean noConsoleNoAnsi)

parse

public java.util.List<PatternFormatter> parse(java.lang.String pattern,
                                              boolean alwaysWriteExceptions,
                                              boolean disableAnsi,
                                              boolean noConsoleNoAnsi)

extractConverter

private static int extractConverter(char lastChar,
                                    java.lang.String pattern,
                                    int start,
                                    java.lang.StringBuilder convBuf,
                                    java.lang.StringBuilder currentLiteral)

Extracts the converter identifier found at the given start position.

After this function returns, the variable i will point to the first char after the end of the converter identifier.

If i points to a char which is not a character acceptable at the start of a unicode identifier, the value null is returned.

Parameters:

lastChar - last processed character.

pattern - format string.

start - current index into pattern format.

convBuf - buffer to receive conversion specifier.

currentLiteral - literal to be output in case format specifier in unrecognized.

Returns:

position in pattern after converter.

extractOptions

private static int extractOptions(java.lang.String pattern,
                                  int start,
                                  java.util.List<java.lang.String> options)

Extract options.

Parameters:

pattern - conversion pattern.

start - start of options.

options - array to receive extracted options

Returns:

position in pattern after options.

parse

public void parse(java.lang.String pattern,
                  java.util.List<PatternConverter> patternConverters,
                  java.util.List<FormattingInfo> formattingInfos,
                  boolean noConsoleNoAnsi,
                  boolean convertBackslashes)

Parse a format specifier.

Parameters:

pattern - pattern to parse.

patternConverters - list to receive pattern converters.

formattingInfos - list to receive field specifiers corresponding to pattern converters.

noConsoleNoAnsi - do not do not output ANSI escape codes if System.console()

convertBackslashes - if true, backslash characters are treated as escape characters and character sequences like "\" followed by "t" (backslash+t) are converted to special characters like '\t' (tab).

parse

public void parse(java.lang.String pattern,
                  java.util.List<PatternConverter> patternConverters,
                  java.util.List<FormattingInfo> formattingInfos,
                  boolean disableAnsi,
                  boolean noConsoleNoAnsi,
                  boolean convertBackslashes)

Parse a format specifier.

Parameters:

pattern - pattern to parse.

patternConverters - list to receive pattern converters.

formattingInfos - list to receive field specifiers corresponding to pattern converters.

disableAnsi - do not output ANSI escape codes

noConsoleNoAnsi - do not do not output ANSI escape codes if System.console()

convertBackslashes - if true, backslash characters are treated as escape characters and character sequences like "\" followed by "t" (backslash+t) are converted to special characters like '\t' (tab).

createConverter

private PatternConverter createConverter(java.lang.String converterId,
                                         java.lang.StringBuilder currentLiteral,
                                         java.util.Map<java.lang.String,java.lang.Class<PatternConverter>> rules,
                                         java.util.List<java.lang.String> options,
                                         boolean disableAnsi,
                                         boolean noConsoleNoAnsi)

Creates a new PatternConverter.

Parameters:

converterId - converterId.

currentLiteral - literal to be used if converter is unrecognized or following converter if converterId contains extra characters.

rules - map of stock pattern converters keyed by format specifier.

options - converter options.

disableAnsi - do not output ANSI escape codes

noConsoleNoAnsi - do not do not output ANSI escape codes if System.console()

Returns:

converter or null.

areValidNewInstanceParameters

private static boolean areValidNewInstanceParameters(java.lang.Class<?>[] parameterTypes)

LOG4J2-2564: Returns true if all method parameters are valid for injection.

finalizeConverter

private int finalizeConverter(char c,
                              java.lang.String pattern,
                              int start,
                              java.lang.StringBuilder currentLiteral,
                              FormattingInfo formattingInfo,
                              java.util.Map<java.lang.String,java.lang.Class<PatternConverter>> rules,
                              java.util.List<PatternConverter> patternConverters,
                              java.util.List<FormattingInfo> formattingInfos,
                              boolean disableAnsi,
                              boolean noConsoleNoAnsi,
                              boolean convertBackslashes)

Processes a format specifier sequence.

Parameters:

c - initial character of format specifier.

pattern - conversion pattern

start - current position in conversion pattern.

currentLiteral - current literal.

formattingInfo - current field specifier.

rules - map of stock pattern converters keyed by format specifier.

patternConverters - list to receive parsed pattern converter.

formattingInfos - list to receive corresponding field specifier.

disableAnsi - do not output ANSI escape codes

noConsoleNoAnsi - do not do not output ANSI escape codes if System.console()

convertBackslashes - if true, backslash characters are treated as escape characters and character sequences like "\" followed by "t" (backslash+t) are converted to special characters like '\t' (tab).

Returns:

position after format specifier sequence.

literalPattern

private LogEventPatternConverter literalPattern(java.lang.String literal,
                                                boolean convertBackslashes)