Module ch.qos.logback.classic

Package ch.qos.logback.classic.sift

Class MDCBasedDiscriminator

java.lang.Object

ch.qos.logback.core.spi.ContextAwareBase

ch.qos.logback.core.sift.AbstractDiscriminator<ILoggingEvent>

ch.qos.logback.classic.sift.MDCBasedDiscriminator

All Implemented Interfaces:

Discriminator<ILoggingEvent>, ContextAware, LifeCycle

public class MDCBasedDiscriminator
extends AbstractDiscriminator<ILoggingEvent>

MDCBasedDiscriminator essentially returns the value mapped to an MDC key. If the said value is null, then a default value is returned.

Both Key and the DefaultValue are user specified properties.

MDC values containing any of the characters /, \, $, {, }, [, ], (, ) , |, ?, *, +, %, ,, @ or the sequence .. are rejected, in which case the default value is returned. This prevents path separators, relative path components, variable substitutions such as ${file.separator}, regex special characters as well as the anchor character '%' or the ',' and '@' characters from leaking into file names or email addresses.

Moreover, the maximum length of an MDC value is limited to 64 characters.

Author:

Ceki Gülcü

Field Summary

Fields inherited from class ch.qos.logback.core.sift.AbstractDiscriminator

started

Fields inherited from class ch.qos.logback.core.spi.ContextAwareBase

context

Constructor Summary

Constructors

Constructor	Description
MDCBasedDiscriminator()

Method Summary

Modifier and Type	Method	Description
String	getDefaultValue()
String	getDiscriminatingValue(ILoggingEvent event)	Return the value associated with an MDC entry designated by the Key property.
String	getKey()	The key or variable name under which the discriminating value should be exported into the host environment.
void	setDefaultValue(String defaultValue)	The default MDC value in case the MDC is not set for mdcKey.
void	setKey(String key)
void	start()

Methods inherited from class ch.qos.logback.core.sift.AbstractDiscriminator

isStarted, stop

Methods inherited from class ch.qos.logback.core.spi.ContextAwareBase

addError, addError, addInfo, addInfo, addStatus, addWarn, addWarn, getContext, getDeclaredOrigin, getStatusManager, setContext

Methods inherited from class java.lang.Object

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

Constructor Detail

MDCBasedDiscriminator

public MDCBasedDiscriminator()

Method Detail

start

public void start()

Specified by:

start in interface LifeCycle

Overrides:

start in class AbstractDiscriminator<ILoggingEvent>

getDiscriminatingValue

public String getDiscriminatingValue(ILoggingEvent event)

Return the value associated with an MDC entry designated by the Key property. If that value is null, then return the value assigned to the DefaultValue property.

If the MDC value contains any of the characters /, \, $, { or }, or the sequence .., then the value assigned to the DefaultValue property is returned.

Returns:

getKey

public String getKey()

Description copied from interface: Discriminator

The key or variable name under which the discriminating value should be exported into the host environment.

Returns:

setKey

public void setKey(String key)

getDefaultValue

public String getDefaultValue()

Returns:

See Also:

setDefaultValue(String)

setDefaultValue

public void setDefaultValue(String defaultValue)

The default MDC value in case the MDC is not set for mdcKey.

For example, if Key is set to the value "someKey", and the MDC is not set for "someKey", then this appender will use the default value, which you can set with the help of this method.

Parameters:

defaultValue -