MDC Class Reference

The MDC class is similar to the NDC class except that it is based on a map instead of a stack. More...

Public Types
typedef std::map< LogString, LogString >	Map
	String to string stl map. More...

Public Member Functions
	MDC (const std::string &key, const std::string &value)
	Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor. More...
	~MDC ()
	MDC (const std::wstring &key, const std::wstring &value)
	Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor. More...
	MDC (const std::basic_string< UniChar > &key, const std::basic_string< UniChar > &value)
	Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor. More...
	MDC (const CFStringRef &key, const CFStringRef &value)
	Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor. More...

Static Public Member Functions
static void	put (const std::string &key, const std::string &value)
	Put a context value (the o parameter) as identified with the key parameter into the current thread's context map. More...
static void	putLS (const LogString &key, const LogString &value)
	Put a context value (the o parameter) as identified with the key parameter into the current thread's context map. More...
static std::string	get (const std::string &key)
	Get the context identified by the key parameter. More...
static bool	get (const LogString &key, LogString &dest)
	Gets the context identified by the key parameter. More...
static std::string	remove (const std::string &key)
	Remove the the context identified by the key parameter. More...
static void	put (const std::wstring &key, const std::wstring &value)
	Put a context value (the o parameter) as identified with the key parameter into the current thread's context map. More...
static std::wstring	get (const std::wstring &key)
	Get the context identified by the key parameter. More...
static std::wstring	remove (const std::wstring &key)
	Remove the the context identified by the key parameter. More...
static void	put (const std::basic_string< UniChar > &key, const std::basic_string< UniChar > &value)
	Put a context value (the o parameter) as identified with the key parameter into the current thread's context map. More...
static std::basic_string< UniChar >	get (const std::basic_string< UniChar > &key)
	Get the context identified by the key parameter. More...
static std::basic_string< UniChar >	remove (const std::basic_string< UniChar > &key)
	Remove the the context identified by the key parameter. More...
static void	put (const CFStringRef &key, const CFStringRef &value)
	Put a context value (the o parameter) as identified with the key parameter into the current thread's context map. More...
static CFStringRef	get (const CFStringRef &key)
	Get the context identified by the key parameter. More...
static CFStringRef	remove (const CFStringRef &key)
	Remove the the context identified by the key parameter. More...
static bool	remove (const LogString &key, LogString &prevValue)
	Remove the the context identified by the key parameter. More...
static void	clear ()
	Clear all entries in the MDC. More...

Detailed Description

The MDC class is similar to the NDC class except that it is based on a map instead of a stack.

It provides mapped diagnostic contexts. A Mapped Diagnostic Context, or MDC in short, is an instrument for distinguishing interleaved log output from different sources. Log output is typically interleaved when a server handles multiple clients near-simultaneously.

The MDC is managed on a per thread basis. A child thread automatically inherits a copy of the mapped diagnostic context of its parent.

Member Typedef Documentation

typedef std::map<LogString, LogString> Map

String to string stl map.

Constructor & Destructor Documentation

MDC	(	const std::string &	key,
		const std::string &	value
	)

Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor.

Both construction and destruction are expected to be on the same thread.

Parameters

key	key
value	value.

~MDC

(

)

MDC	(	const std::wstring &	key,
		const std::wstring &	value
	)

Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor.

Both construction and destruction are expected to be on the same thread.

Parameters

key	key
value	value.

MDC	(	const std::basic_string< UniChar > &	key,
		const std::basic_string< UniChar > &	value
	)

Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor.

Both construction and destruction are expected to be on the same thread.

Parameters

key	key
value	value.

MDC	(	const CFStringRef &	key,
		const CFStringRef &	value
	)

Places a key/value pair in the MDC for the current thread which will be removed during the corresponding destructor.

Both construction and destruction are expected to be on the same thread.

Parameters

key	key
value	value.

Member Function Documentation

static void clear ( )

static

Clear all entries in the MDC.

static std::string get ( const std::string &  key )

static

Get the context identified by the key parameter.

This method has no side effects.

Parameters

key

key.

Returns

value for key, empty if not set.

static bool get ( const LogString &  key, LogString &  dest  )

static

Gets the context identified by the key parameter.

Parameters

key	context key.
dest	destination to which value is appended.

Returns

true if key has associated value.

static std::wstring get ( const std::wstring &  key )

static

Get the context identified by the key parameter.

This method has no side effects.

Parameters

key

key.

Returns

value for key, empty if not set.

static std::basic_string<UniChar> get ( const std::basic_string< UniChar > &  key )

static

Get the context identified by the key parameter.

This method has no side effects.

Parameters

key

key.

Returns

value for key, empty if not set.

static CFStringRef get ( const CFStringRef &  key )

static

Get the context identified by the key parameter.

This method has no side effects.

Parameters

key

key.

Returns

value for key, empty if not set.

static void put ( const std::string &  key, const std::string &  value  )

static

Put a context value (the o parameter) as identified with the key parameter into the current thread's context map.

If the current thread does not have a context map it is created as a side effect.

Parameters

key	key
value	value.

static void put ( const std::wstring &  key, const std::wstring &  value  )

static

Put a context value (the o parameter) as identified with the key parameter into the current thread's context map.

If the current thread does not have a context map it is created as a side effect.

Parameters

key	key
value	value.

static void put ( const std::basic_string< UniChar > &  key, const std::basic_string< UniChar > &  value  )

static

Put a context value (the o parameter) as identified with the key parameter into the current thread's context map.

If the current thread does not have a context map it is created as a side effect.

Parameters

key	key
value	value.

static void put ( const CFStringRef &  key, const CFStringRef &  value  )

static

Put a context value (the o parameter) as identified with the key parameter into the current thread's context map.

If the current thread does not have a context map it is created as a side effect.

Parameters

key	key
value	value.

static void putLS ( const LogString &  key, const LogString &  value  )

static

Put a context value (the o parameter) as identified with the key parameter into the current thread's context map.

If the current thread does not have a context map it is created as a side effect.

static std::string remove ( const std::string &  key )

static

Remove the the context identified by the key parameter.

Parameters

key

key.

Returns

value if key had been set, empty if not.

static std::wstring remove ( const std::wstring &  key )

static

Remove the the context identified by the key parameter.

Parameters

key

key.

Returns

value if key had been set, empty if not.

static std::basic_string<UniChar> remove ( const std::basic_string< UniChar > &  key )

static

Remove the the context identified by the key parameter.

Parameters

key

key.

Returns

value if key had been set, empty if not.

static CFStringRef remove ( const CFStringRef &  key )

static

Remove the the context identified by the key parameter.

Parameters

key

key.

Returns

value if key had been set, empty if not.

static bool remove ( const LogString &  key, LogString &  prevValue  )

static

Remove the the context identified by the key parameter.

Parameters

key	key.
prevValue	buffer to which previous value is appended.

Returns

true if key existed in MDC.

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

• mdc.h