PropertyConfigurator Class Reference

Inherits Configurator, and ObjectImpl.

List of all members.


Detailed Description

Allows the configuration of log4cxx from an external file.

See doConfigure(const File&, log4cxx::spi::LoggerRepositoryPtr&) for the expected format.

It is sometimes useful to see how log4cxx is reading configuration files. You can enable log4cxx internal logging by defining the log4j.debug variable.

At class initialization time class, the file log4j.properties will be searched in the current directory. If the file can be found, then it will be fed to the PropertyConfigurator#configure(const File& configFilename) method.

The PropertyConfigurator does not handle the advanced configuration features supported by the DOMConfigurator such as support for Filters, custom ErrorHandlers, nested appenders such as the AsyncAppender, etc.

All option values admit variable substitution. The syntax of variable substitution is similar to that of Unix shells. The string between an opening "${" and closing "}" is interpreted as a key. The value of the substituted variable can be defined as a system property or in the configuration file itself. The value of the key is first searched in the system properties, and if not found there, it is then searched in the configuration file being parsed. The corresponding value replaces the ${variableName} sequence. For example, if java.home system property is set to /home/xyz, then every occurrence of the sequence ${java.home} will be interpreted as /home/xyz.


Public Member Functions

 PropertyConfigurator ()
virtual ~PropertyConfigurator ()
void addRef () const
void releaseRef () const
void doConfigure (const File &configFileName, spi::LoggerRepositoryPtr &hierarchy)
 Read configuration from a file.
void doConfigure (helpers::Properties &properties, spi::LoggerRepositoryPtr &hierarchy)
 Read configuration options from properties.

Static Public Member Functions

static void configure (const File &configFilename)
 Read configuration options from file configFilename.
static void configureAndWatch (const File &configFilename)
 Like configureAndWatch(const File& configFilename, long delay) except that the default delay as defined by helpers::FileWatchdog::DEFAULT_DELAY is used.
static void configureAndWatch (const File &configFilename, long delay)
 Read the configuration file configFilename if it exists.
static void configure (helpers::Properties &properties)
 Read configuration options from properties.

Protected Member Functions

void configureLoggerFactory (helpers::Properties &props)
 Check the provided Properties object for a loggerFactory entry specified by LOGGER_FACTORY_KEY.
void configureRootLogger (helpers::Properties &props, spi::LoggerRepositoryPtr &hierarchy)
void parseCatsAndRenderers (helpers::Properties &props, spi::LoggerRepositoryPtr &hierarchy)
 Parse non-root elements, such non-root categories and renderers.
void parseAdditivityForLogger (helpers::Properties &props, LoggerPtr &cat, const LogString &loggerName)
 Parse the additivity option for a non-root logger.
void parseLogger (helpers::Properties &props, LoggerPtr &logger, const LogString &optionKey, const LogString &loggerName, const LogString &value)
 This method must work for the root logger as well.
AppenderPtr parseAppender (helpers::Properties &props, const LogString &appenderName)
void registryPut (const AppenderPtr &appender)
AppenderPtr registryGet (const LogString &name)

Protected Attributes

std::map< LogString, AppenderPtr > * registry
 Used internally to keep track of configured appenders.
helpers::ObjectPtrT< spi::LoggerFactoryloggerFactory
 Used to create new instances of logger.


Constructor & Destructor Documentation

PropertyConfigurator  ) 
 

virtual ~PropertyConfigurator  )  [virtual]
 


Member Function Documentation

void addRef  )  const [virtual]
 

Reimplemented from ObjectImpl.

static void configure helpers::Properties properties  )  [static]
 

Read configuration options from properties.

See doConfigure(const File&, log4cxx::spi::LoggerRepositoryPtr&) for the expected format.

static void configure const File configFilename  )  [static]
 

Read configuration options from file configFilename.

static void configureAndWatch const File configFilename,
long  delay
[static]
 

Read the configuration file configFilename if it exists.

Moreover, a thread will be created that will periodically check if configFilename has been created or modified. The period is determined by the delay argument. If a change or file creation is detected, then configFilename is read to configure log4j.

Parameters:
configFilename A file in key=value format.
delay The delay in milliseconds to wait between each check.

static void configureAndWatch const File configFilename  )  [static]
 

Like configureAndWatch(const File& configFilename, long delay) except that the default delay as defined by helpers::FileWatchdog::DEFAULT_DELAY is used.

Parameters:
configFilename A file in key=value format.

void configureLoggerFactory helpers::Properties props  )  [protected]
 

Check the provided Properties object for a loggerFactory entry specified by LOGGER_FACTORY_KEY.

If such an entry exists, an attempt is made to create an instance using the default constructor. This instance is used for subsequent Logger creations within this configurator.

See also:
parseCatsAndRenderers

void configureRootLogger helpers::Properties props,
spi::LoggerRepositoryPtr hierarchy
[protected]
 

void doConfigure helpers::Properties properties,
spi::LoggerRepositoryPtr hierarchy
 

Read configuration options from properties.

See doConfigure(const File&, log4cxx::spi::LoggerRepositoryPtr&) for the expected format.

void doConfigure const File configFileName,
spi::LoggerRepositoryPtr hierarchy
[virtual]
 

Read configuration from a file.

The existing configuration is not cleared nor reset. If you require a different behavior, then call resetConfiguration method before calling doConfigure.

The configuration file consists of statements in the format key=value. The syntax of different configuration elements are discussed below.

Repository-wide threshold

The repository-wide threshold filters logging requests by level regardless of logger. The syntax is:

log4j.threshold=[level]

The level value can consist of the string values OFF, FATAL, ERROR, WARN, INFO, DEBUG, ALL or a custom level value. A custom level value can be specified in the form level::classname. By default the repository-wide threshold is set to the lowest possible value, namely the level ALL.

Appender configuration

Appender configuration syntax is:

# For appender named appenderName, set its class.
# Note: The appender name can contain dots.
log4j.appender.appenderName=fully.qualified.name.of.appender.class

# Set appender specific options.
log4j.appender.appenderName.option1=value1
...
log4j.appender.appenderName.optionN=valueN

For each named appender you can configure its Layout. The syntax for configuring an appender's layout is:

log4j.appender.appenderName.layout=fully.qualified.name.of.layout.class
log4j.appender.appenderName.layout.option1=value1
....
log4j.appender.appenderName.layout.optionN=valueN

Configuring loggers

The syntax for configuring the root logger is:

log4j.rootLogger=[level], appenderName, appenderName, ...

This syntax means that an optional level can be supplied followed by appender names separated by commas.

The level value can consist of the string values OFF, FATAL, ERROR, WARN, INFO, DEBUG, ALL or a custom level value. A custom level value can be specified in the form level::classname.

If a level value is specified, then the root level is set to the corresponding level. If no level value is specified, then the root level remains untouched.

The root logger can be assigned multiple appenders.

Each appenderName (separated by commas) will be added to the root logger. The named appender is defined using the appender syntax defined above.

For non-root categories the syntax is almost the same:

log4j.logger.logger_name=[level|INHERITED|NULL], appenderName, appenderName,
...

The meaning of the optional level value is discussed above in relation to the root logger. In addition however, the value INHERITED can be specified meaning that the named logger should inherit its level from the logger hierarchy.

If no level value is supplied, then the level of the named logger remains untouched.

By default categories inherit their level from the hierarchy. However, if you set the level of a logger and later decide that that logger should inherit its level, then you should specify INHERITED as the value for the level value. NULL is a synonym for INHERITED.

Similar to the root logger syntax, each appenderName (separated by commas) will be attached to the named logger.

See the appender additivity rule in the user manual for the meaning of the additivity flag.

Logger Factories

The usage of custom logger factories is discouraged and no longer documented.

Example

An example configuration is given below. Other configuration file examples are given in the examples folder.

# Set options for appender named "A1".
# Appender "A1" will be a SyslogAppender
log4j.appender.A1=SyslogAppender

# The syslog daemon resides on www.abc.net
log4j.appender.A1.SyslogHost=www.abc.net

# A1's layout is a PatternLayout, using the conversion pattern
# r -5p c{2} M.L x - m
. Thus, the log output will # include # the relative time since the start of the application in # milliseconds, followed by the level of the log request, # followed by the two rightmost components of the logger name, # followed by the callers method name, followed by the line number, # the nested disgnostic context and finally the message itself. # Refer to the documentation of PatternLayout for further information # on the syntax of the ConversionPattern key. log4j.appender.A1.layout=PatternLayout log4j.appender.A1.layout.ConversionPattern=-4r -5p c{2} M.L x - m

# Set options for appender named "A2"
# A2 should be a RollingFileAppender, with maximum file size of 10 MB
# using at most one backup file. A2's layout is TTCC, using the
# ISO8061 date format with context printing enabled.
log4j.appender.A2=RollingFileAppender
log4j.appender.A2.MaxFileSize=10MB
log4j.appender.A2.MaxBackupIndex=1
log4j.appender.A2.layout=TTCCLayout
log4j.appender.A2.layout.ContextPrinting=enabled
log4j.appender.A2.layout.DateFormat=ISO8601

# Root logger set to DEBUG using the A2 appender defined above.
log4j.rootLogger=DEBUG, A2

# Logger definitions:
# The SECURITY logger inherits is level from root. However, it's output
# will go to A1 appender defined above. It's additivity is non-cumulative.
log4j.logger.SECURITY=INHERIT, A1
log4j.additivity.SECURITY=false

# Only warnings or above will be logged for the logger "SECURITY.access".
# Output will go to A1.
log4j.logger.SECURITY.access=WARN

# The logger "class.of.the.day" inherits its level from the
# logger hierarchy.  Output will go to the appender's of the root
# logger, A2 in this case.
log4j.logger.class.of.the.day=INHERIT

Refer to the setOption method in each Appender and Layout for class specific options.

Use the # or ! characters at the beginning of a line for comments.

Parameters:
configFileName The name of the configuration file where the configuration information is stored.
hierarchy The hierarchy to operation upon.

Implements Configurator.

void parseAdditivityForLogger helpers::Properties props,
LoggerPtr cat,
const LogString loggerName
[protected]
 

Parse the additivity option for a non-root logger.

AppenderPtr parseAppender helpers::Properties props,
const LogString appenderName
[protected]
 

void parseCatsAndRenderers helpers::Properties props,
spi::LoggerRepositoryPtr hierarchy
[protected]
 

Parse non-root elements, such non-root categories and renderers.

void parseLogger helpers::Properties props,
LoggerPtr logger,
const LogString optionKey,
const LogString loggerName,
const LogString value
[protected]
 

This method must work for the root logger as well.

AppenderPtr registryGet const LogString name  )  [protected]
 

void registryPut const AppenderPtr appender  )  [protected]
 

void releaseRef  )  const [virtual]
 

Reimplemented from ObjectImpl.


Member Data Documentation

helpers::ObjectPtrT<spi::LoggerFactory> loggerFactory [protected]
 

Used to create new instances of logger.

std::map<LogString, AppenderPtr>* registry [protected]
 

Used internally to keep track of configured appenders.


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