MetaInfo Class Reference

Collaboration diagram for MetaInfo:

Class Description

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This class is a sort of plug-in for the TextLogger class. Its purpose is to assemble the meta information of each log line (things like timestamps, thread information, verbosity and domain, etc.).

To manipulate the meta information log output, three options exist:

• by just changing the format string (at runtime).
• by creating a derived class that introduces a new version of method processVariable() to handle one or more format variable differently or to introduce new variables.
• by creating a derived class that introduces a new version of method write() to completely control the meta information output.

Public Fields
String	dateFormat = "yyyy-MM-dd"
SimpleDateFormat	dateFormatter
AString	format = new AString( "(%SF:%SL) %SM():%A5[%TC +%TL][%tN]%V[%D]%A1(%#): ")
int	logNumberMinDigits = 3
Ticks	maxElapsedTime = new Ticks(0)
String	timeDiffDays = " days"
String	timeDiffHours = " h"
String	timeDiffMicros = " \u00B5s"
String	timeDiffMillis = " ms"
long	timeDiffMinimum = 1000L
	Minimum time difference to log in nanoseconds. Below that timeDiffNone is written.
String	timeDiffMins = " m"
String	timeDiffNanos = " ns"
String	timeDiffNone = " 0 ns"
	Output for time difference if below reasonable (measurable) minimum defined in timeDiffMinimum.
String	timeDiffSecs = " s"
String	timeElapsedDays = " Days "
String	timeOfDayFormat = "HH:mm:ss"
SimpleDateFormat	timeOfDayFormatter
String	verbosityError = "[ERR]"
String	verbosityInfo = " "
String	verbosityVerbose = "[***]"
String	verbosityWarning = "[WRN]"

Protected Fields
boolean	calInstanceSet
GregorianCalendar	callerDateTimeCal = new GregorianCalendar()
Date	callerDateTimeDate = new Date()
boolean	dateInstanceSet
String	defaultfmtDate = "yyyy-MM-dd"
String	defaultfmtTimeOfDay = "HH:mm:ss"
TickSpan	elapsed = new TickSpan()
Ticks	elapsedTime = new Ticks(0)
FieldPosition	fieldPositionZero = new FieldPosition( 0 )
int[]	tempIntParameter = new int[1]
StringBuffer	tempSBuf = new StringBuffer()
AString	tmpAString = new AString()
Tokenizer	tTok = new Tokenizer()
	Tokenizer used in write.
boolean	warnedOnce = false

Protected Methods
void	processVariable (TextLogger logger, Domain domain, Verbosity verbosity, ScopeInfo scope, AString dest, Substring variable)
void	write (TextLogger logger, AString buf, Domain domain, Verbosity verbosity, ScopeInfo scope)
void	writeTimeDiff (AString buf, long diffNanos)

Member Function Documentation

processVariable()

void processVariable ( TextLogger  logger, Domain  domain, Verbosity  verbosity, ScopeInfo  scope, AString  dest, Substring  variable  )

protected

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Processes the next command found in the format string, by writing formatted information into the given buffer. The given Substring holds the next command. When method returns, the command is cut from the front.

Parameters

logger	The logger that we are embedded in.
domain	The Log Domain.
verbosity	The verbosity. This has been checked to be active already on this stage and is provided to be able to be logged out only.
scope	Information about the scope of the Log Statement..
dest	The buffer to write meta information into.
variable	The variable to read (may have more characters appended)

write()

void write ( TextLogger  logger, AString  buf, Domain  domain, Verbosity  verbosity, ScopeInfo  scope  )

protected

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Parses the format string and logs meta information into the log buffer. For each variable found, method processVariable is invoked. Hence, to add new variables, the latter method can be overwritten by descendants. Overwriting this method is recommended for formatter classes that do not rely on format strings.

Parameters

logger	The logger that we are embedded in.
buf	The buffer to write meta information into.
domain	The Log Domain.
verbosity	The verbosity. This has been checked to be active already on this stage and is provided to be able to be logged out only.
scope	Information about the scope of the Log Statement..

writeTimeDiff()

void writeTimeDiff ( AString  buf, long  diffNanos  )

protected

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Helper function that logs a time given difference into the given buffer in a human readable format. Works from nano seconds to days.

Parameters

buf	The buffer to write the time difference representation into.
diffNanos	The time difference to write in nanoseconds.

Member Data Documentation

calInstanceSet

boolean calInstanceSet

protected

Flag to indicate if calendar instance was set during one logText call

callerDateTimeCal

GregorianCalendar callerDateTimeCal = new GregorianCalendar()

protected

Internal calendar object to get string representations of dates.

callerDateTimeDate

Date callerDateTimeDate = new Date()

protected

Internal calendar object to get string representations of dates.

dateFormat

String dateFormat = "yyyy-MM-dd"

Format string for the output of the log date. For more information about possible, see class java.text.SimpleDateFormat

dateFormatter

SimpleDateFormat dateFormatter

Object to retrieve formatted log date. This field has to be set to null, when the field dateFormat gets modified and log operations have been scheduled since the creation of the Logger (respectively since the last change of that format).

dateInstanceSet

boolean dateInstanceSet

protected

Flag to indicate if date instance was set during one logText call

defaultfmtDate

String defaultfmtDate = "yyyy-MM-dd"

protected

Internal default string to detect default format for optimized format generation

defaultfmtTimeOfDay

String defaultfmtTimeOfDay = "HH:mm:ss"

protected

Internal default string to detect default format for optimized format generation

elapsed

TickSpan elapsed = new TickSpan()

protected

A reusable object for displaying the elapsed time span

elapsedTime

Ticks elapsedTime = new Ticks(0)

protected

A reusable object for displaying the elapsed time

fieldPositionZero

FieldPosition fieldPositionZero = new FieldPosition( 0 )

protected

Internal singleton to specify a first field in formatted output

format

AString format = new AString( "(%SF:%SL) %SM():%A5[%TC +%TL][%tN]%V[%D]%A1(%#): ")

The line format specifies the (automated) log output that is prepended to each log line before the log message itself.

The string supports replacement variables that begin with a % sign

• SF: The callers' source file name
• SP: The callers' package name
• SC: The callers' class name
• SL: The line number in the callers' source file
• SM: The method name
• TD: The date the log call was invoked
• TT: Time of day the log call was invoked
• TC: Time elapsed since the Logger was created or its timer was reset
• TL: Time elapsed since the last log call
• tN: Thread name
• tI: Thread ID
• V: The verbosity. This is replaced by the corresponding strings found in fields verbosityError, verbosityWarning, verbosityInfo and verbosityVerbose.
• D: Log domain
• %#: The log call counter (like a line counter, but counting multi lines as one)
• An: An auto-adjusted tabulator. This grows whenever it needs, but never shrinks. The optional integer number n specifies how much extra space is added when tab is adjusted. Setting this to a higher value avoids too many adjustments at the beginning of a log session.
• LG: The name of the Logger. This might be useful if multiple loggers write to the same output stream (e.g. Console).
• LX: The name of the Lox.
• P: The name of the process / application.

Defaults to

"(%SF:%SL) %SM():%A5[%TC +%TL][%tN]%V[%D]%A1(%#): " 

logNumberMinDigits

int logNumberMinDigits = 3

Prefix for the domain.

maxElapsedTime

Ticks maxElapsedTime = new Ticks(0)

The maximum time elapsed. Used to determine the width of the output when writing the elapsed time.

This field will be read from the configuration variable ALOX_LOGGERNAME_MAX_ELAPSED_TIME when the TextLogger that this object belongs to is attached to a Lox and written back on removal.

tempIntParameter

int [] tempIntParameter = new int[1]

protected

Internal object to pass int parameters to methods that modify those

tempSBuf

StringBuffer tempSBuf = new StringBuffer()

protected

Internal object to retrieve formatted time of day

timeDiffDays

String timeDiffDays = " days"

Format for time difference outputs of more than a day.

timeDiffHours

String timeDiffHours = " h"

Format for time difference outputs between 1h and 24h.

timeDiffMicros

String timeDiffMicros = " \u00B5s"

Entity microseconds

timeDiffMillis

String timeDiffMillis = " ms"

Entity milliseconds

timeDiffMins

String timeDiffMins = " m"

Format for time difference outputs between 100s and 60 min.

timeDiffNanos

String timeDiffNanos = " ns"

Entity milliseconds.

timeDiffSecs

String timeDiffSecs = " s"

Format for time difference outputs between 10s and 99.9s.

timeElapsedDays

String timeElapsedDays = " Days "

The word "Days" the out put of time elapsed (if longer than a day).

timeOfDayFormat

String timeOfDayFormat = "HH:mm:ss"

Format string for the output of the time of day. For more information about possible, see class java.text.SimpleDateFormat

timeOfDayFormatter

SimpleDateFormat timeOfDayFormatter

Object to retrieve formatted time of day. This field has to be set to null, when the field timeOfDayFormat gets modified and log operations have been scheduled since the creation of the Logger (respectively since the last change of that format).

tmpAString

AString tmpAString = new AString()

protected

A reusable AString .

verbosityError

String verbosityError = "[ERR]"

The replacement for variable %V in field format if Verbosity is ERROR

verbosityInfo

String verbosityInfo = " "

The replacement for variable %V in field format if Verbosity is INFO

verbosityVerbose

String verbosityVerbose = "[***]"

The replacement for variable %V in field format if Verbosity is VERBOSE

verbosityWarning

String verbosityWarning = "[WRN]"

The replacement for variable %V in field format if Verbosity is WARNING

warnedOnce

boolean warnedOnce = false

protected

Helper flag that indicates if a format warning report was already issued

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The documentation for this class was generated from the following file:

• MetaInfo.java