WriterAppender appends log events to a standard output stream. More...

#include <writerappender.h>

Inheritance diagram for log4cxx::WriterAppender:

Public Member Functions
	WriterAppender ()
	This default constructor does nothing.

	~WriterAppender ()

void	activateOptions (helpers::Pool &pool) override
	Derived appenders should override this method if option structure requires it.

void	setImmediateFlush (bool value)
	If the ImmediateFlush option is set to `true`, the appender will flush at the end of each write.

bool	getImmediateFlush () const
	Returns value of the ImmediateFlush option.

void	append (const spi::LoggingEventPtr &event, helpers::Pool &p) override
	This method is called by the AppenderSkeleton::doAppend method.

void	close () override
	Close this appender instance.

LogString	getEncoding () const

void	setEncoding (const LogString &value)

void	setOption (const LogString &option, const LogString &value) override
	Set `option` to `value`.

void	setWriter (const log4cxx::helpers::WriterPtr &writer)

const log4cxx::helpers::WriterPtr	getWriter () const

bool	requiresLayout () const override
	Configurators call this method to determine if the appender requires a layout.

Public Member Functions inherited from log4cxx::AppenderSkeleton
	AppenderSkeleton ()

	AppenderSkeleton (const LayoutPtr &layout)

virtual	~AppenderSkeleton ()

void	finalize ()
	Finalize this appender by calling the derived class' `close` method.

void	activateOptions (helpers::Pool &) override
	Derived appenders should override this method if option structure requires it.

void	setOption (const LogString &option, const LogString &value) override
	Set `option` to `value`.

void	addFilter (const spi::FilterPtr newFilter) override
	Add a filter to end of the filter list.

void	clearFilters () override
	Clear the filters chain.

const spi::ErrorHandlerPtr	getErrorHandler () const
	Return the currently set spi::ErrorHandler for this Appender.

spi::FilterPtr	getFilter () const override
	Returns the head Filter.

const spi::FilterPtr	getFirstFilter () const
	Return the first filter in the filter chain for this Appender.

LayoutPtr	getLayout () const override
	Returns the layout of this appender.

LogString	getName () const override
	Returns the name of this Appender.

const LevelPtr	getThreshold () const
	Returns this appenders threshold level.

bool	isAsSevereAsThreshold (const LevelPtr &level) const
	Check whether the message level is below the appender's threshold.

void	doAppend (const spi::LoggingEventPtr &event, helpers::Pool &pool) override
	This method performs threshold checks and invokes filters before delegating actual logging to the subclasses specific AppenderSkeleton::append method.

void	setErrorHandler (const spi::ErrorHandlerPtr eh)
	Set the `ErrorHandler` for this Appender.

void	setLayout (const LayoutPtr layout1) override
	Set the layout for this appender.

void	setName (const LogString &name1) override
	Set the name of this Appender.

void	setThreshold (const LevelPtr &threshold)
	Set the threshold level.

Public Member Functions inherited from log4cxx::Appender
virtual	~Appender ()

virtual void	addFilter (const spi::FilterPtr newFilter)=0
	Add a filter to the end of the filter list.

virtual spi::FilterPtr	getFilter () const =0
	Returns the head Filter.

virtual void	clearFilters ()=0
	Clear the list of filters by removing all the filters in it.

virtual void	close ()=0
	Release any resources allocated within the appender such as file handles, network connections, etc.

virtual void	doAppend (const spi::LoggingEventPtr &event, log4cxx::helpers::Pool &pool)=0
	Log in `Appender` specific way.

virtual LogString	getName () const =0
	Get the name of this appender.

virtual void	setLayout (const LayoutPtr layout)=0
	Set the Layout for this appender.

virtual LayoutPtr	getLayout () const =0
	Returns this appenders layout.

virtual void	setName (const LogString &name)=0
	Set the name of this appender.

virtual bool	requiresLayout () const =0
	Configurators call this method to determine if the appender requires a layout.

Public Member Functions inherited from log4cxx::spi::OptionHandler
virtual	~OptionHandler ()

virtual void	activateOptions (helpers::Pool &p)=0
	Activate the options that were previously set with calls to option setters.

virtual void	setOption (const LogString &option, const LogString &value)=0
	Set `option` to `value`.

Public Member Functions inherited from log4cxx::helpers::Object
virtual	~Object ()

virtual const helpers::Class &	getClass () const =0

virtual bool	instanceof (const Class &clazz) const =0

virtual const void *	cast (const Class &clazz) const =0

Protected Member Functions
	WriterAppender (const LayoutPtr &layout, log4cxx::helpers::WriterPtr &writer)

	WriterAppender (const LayoutPtr &layout)

	WriterAppender (std::unique_ptr< WriterAppenderPriv > priv)

virtual bool	checkEntryConditions () const
	This method determines if there is a sense in attempting to append.

void	closeWriter ()
	Close the underlying `log4cxx::helpers::Writer`.

virtual helpers::WriterPtr	createWriter (helpers::OutputStreamPtr &os)
	Returns an OutputStreamWriter when passed an OutputStream.

virtual void	subAppend (const spi::LoggingEventPtr &event, log4cxx::helpers::Pool &p)
	Actual writing occurs here.

virtual void	writeFooter (log4cxx::helpers::Pool &p)
	Write a footer as produced by the embedded layout's Layout::appendFooter method.

virtual void	writeHeader (log4cxx::helpers::Pool &p)
	Write a header as produced by the embedded layout's Layout::appendHeader method.

void	setWriterInternal (const log4cxx::helpers::WriterPtr &writer)
	Set the writer.

Protected Member Functions inherited from log4cxx::AppenderSkeleton
	AppenderSkeleton (LOG4CXX_PRIVATE_PTR(AppenderSkeletonPrivate) priv)

virtual void	append (const spi::LoggingEventPtr &event, log4cxx::helpers::Pool &p)=0
	Subclasses of `AppenderSkeleton` should implement this method to perform actual logging.

void	doAppendImpl (const spi::LoggingEventPtr &event, log4cxx::helpers::Pool &pool)

Detailed Description

WriterAppender appends log events to a standard output stream.

Constructor & Destructor Documentation

◆ WriterAppender() [1/4]

log4cxx::WriterAppender::WriterAppender ( )

This default constructor does nothing.

◆ WriterAppender() [2/4]

log4cxx::WriterAppender::WriterAppender	(	const LayoutPtr &	layout,
		log4cxx::helpers::WriterPtr &	writer
	)

protected

◆ WriterAppender() [3/4]

log4cxx::WriterAppender::WriterAppender ( const LayoutPtr & layout )

protected

◆ WriterAppender() [4/4]

log4cxx::WriterAppender::WriterAppender ( std::unique_ptr< WriterAppenderPriv > priv )

protected

◆ ~WriterAppender()

log4cxx::WriterAppender::~WriterAppender ( )

Member Function Documentation

◆ activateOptions()

void log4cxx::WriterAppender::activateOptions ( helpers::Pool & pool )

overridevirtual

Derived appenders should override this method if option structure requires it.

Reimplemented from log4cxx::AppenderSkeleton.

◆ append()

void log4cxx::WriterAppender::append	(	const spi::LoggingEventPtr &	event,
		helpers::Pool &	p
	)

overridevirtual

This method is called by the AppenderSkeleton::doAppend method.

If the output stream exists and is writable then write a log statement to the output stream. Otherwise, write a single warning message to stderr.

The format of the output will depend on this appender's layout.

Implements log4cxx::AppenderSkeleton.

◆ checkEntryConditions()

virtual bool log4cxx::WriterAppender::checkEntryConditions ( ) const

protectedvirtual

This method determines if there is a sense in attempting to append.

It checks whether there is a set output target and also if there is a set layout. If these checks fail, then the boolean value false is returned.

◆ close()

void log4cxx::WriterAppender::close ( )

overridevirtual

Close this appender instance.

The underlying stream or writer is also closed.

Closed appenders cannot be reused.

Implements log4cxx::Appender.

◆ closeWriter()

void log4cxx::WriterAppender::closeWriter ( )

protected

Close the underlying log4cxx::helpers::Writer.

◆ createWriter()

virtual helpers::WriterPtr log4cxx::WriterAppender::createWriter ( helpers::OutputStreamPtr & os )

protectedvirtual

Returns an OutputStreamWriter when passed an OutputStream.

The encoding used will depend on the value of the encoding property. If the encoding value is specified incorrectly the writer will be opened using the default system encoding (an error message will be printed to the loglog.

Reimplemented in log4cxx::rolling::MultiprocessRollingFileAppender, and log4cxx::rolling::RollingFileAppender.

◆ getEncoding()

LogString log4cxx::WriterAppender::getEncoding ( ) const

◆ getImmediateFlush()

bool log4cxx::WriterAppender::getImmediateFlush ( ) const

Returns value of the ImmediateFlush option.

◆ getWriter()

const log4cxx::helpers::WriterPtr log4cxx::WriterAppender::getWriter ( ) const

◆ requiresLayout()

bool log4cxx::WriterAppender::requiresLayout ( ) const

overridevirtual

Configurators call this method to determine if the appender requires a layout.

If this method returns true, meaning that layout is required, then the configurator will configure an layout using the configuration information at its disposal. If this method returns false, meaning that a layout is not required, then layout configuration will be skipped even if there is available layout configuration information at the disposal of the configurator..

In the rather exceptional case, where the appender implementation admits a layout but can also work without it, then the appender should return true.

Implements log4cxx::Appender.

◆ setEncoding()

void log4cxx::WriterAppender::setEncoding ( const LogString & value )

◆ setImmediateFlush()

void log4cxx::WriterAppender::setImmediateFlush ( bool value )

If the ImmediateFlush option is set to true, the appender will flush at the end of each write.

This is the default behavior. If the option is set to false, then the underlying stream can defer writing to physical medium to a later time.

Avoiding the flush operation at the end of each append results in a performance gain of 10 to 20 percent. However, there is safety tradeoff involved in skipping flushing. Indeed, when flushing is skipped, then it is likely that the last few log events will not be recorded on disk when the application exits. This is a high price to pay even for a 20% performance gain.

◆ setOption()

void log4cxx::WriterAppender::setOption	(	const LogString &	option,
		const LogString &	value
	)

overridevirtual

Set option to value.

The handling of each option depends on the OptionHandler instance. Some options may become active immediately whereas other may be activated only when activateOptions is called.

Reimplemented from log4cxx::AppenderSkeleton.

◆ setWriter()

void log4cxx::WriterAppender::setWriter ( const log4cxx::helpers::WriterPtr & writer )

Sets the Writer where the log output will go. The specified Writer must be opened by the user and be writable.

The java.io.Writer will be closed when the appender instance is closed.

WARNING: Logging to an unopened Writer will fail.

Parameters

writer An already opened Writer.

◆ setWriterInternal()

void log4cxx::WriterAppender::setWriterInternal ( const log4cxx::helpers::WriterPtr & writer )

protected

Set the writer.

Mutex must already be held.

◆ subAppend()

virtual void log4cxx::WriterAppender::subAppend	(	const spi::LoggingEventPtr &	event,
		log4cxx::helpers::Pool &	p
	)

protectedvirtual

Actual writing occurs here.

Reimplemented in log4cxx::rolling::MultiprocessRollingFileAppender, and log4cxx::rolling::RollingFileAppender.

◆ writeFooter()

virtual void log4cxx::WriterAppender::writeFooter ( log4cxx::helpers::Pool & p )

protectedvirtual

Write a footer as produced by the embedded layout's Layout::appendFooter method.

◆ writeHeader()

virtual void log4cxx::WriterAppender::writeHeader ( log4cxx::helpers::Pool & p )

protectedvirtual

Write a header as produced by the embedded layout's Layout::appendHeader method.

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

writerappender.h

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ WriterAppender() [1/4]

◆ WriterAppender() [2/4]

◆ WriterAppender() [3/4]

◆ WriterAppender() [4/4]

◆ ~WriterAppender()

Member Function Documentation

◆ activateOptions()

◆ append()

◆ checkEntryConditions()

◆ close()

◆ closeWriter()

◆ createWriter()

◆ getEncoding()

◆ getImmediateFlush()

◆ getWriter()

◆ requiresLayout()

◆ setEncoding()

◆ setImmediateFlush()

◆ setOption()

◆ setWriter()

◆ setWriterInternal()

◆ subAppend()

◆ writeFooter()

◆ writeHeader()