Package org.apache.log4j
Class MDC
java.lang.Object
org.apache.log4j.MDC
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.
The MDC class requires JDK 1.2 or above. Under JDK 1.1 the MDC will always return empty values but otherwise will not affect or harm your application.
- Since:
- 1.2
- Author:
- Ceki Gülcü
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Method Summary
Modifier and TypeMethodDescriptionstatic voidclear()Remove all values from the MDC.static ObjectGet the context identified by thekeyparameter.static HashtableGet the current thread's MDC as a hashtable.static voidPut a context value (theoparameter) as identified with thekeyparameter into the current thread's context map.static voidRemove the the context identified by thekeyparameter.
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Method Details
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put
Put a context value (theoparameter) as identified with thekeyparameter into the current thread's context map.If the current thread does not have a context map it is created as a side effect.
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get
Get the context identified by thekeyparameter.This method has no side effects.
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remove
Remove the the context identified by thekeyparameter. -
getContext
Get the current thread's MDC as a hashtable. This method is intended to be used internally. -
clear
public static void clear()Remove all values from the MDC.- Since:
- 1.2.16
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