org.apache.logging.log4j.core.selector

Class ClassLoaderContextSelector

java.lang.Object

org.apache.logging.log4j.core.selector.ClassLoaderContextSelector

All Implemented Interfaces:

ContextSelector, LoggerContextShutdownAware

Direct Known Subclasses:

AsyncLoggerContextSelector, BundleContextSelector

public class ClassLoaderContextSelector
extends Object
implements ContextSelector, LoggerContextShutdownAware

This ContextSelector chooses a LoggerContext based upon the ClassLoader of the caller. This allows Loggers assigned to static variables to be released along with the classes that own then. Other ContextSelectors will generally cause Loggers associated with classes loaded from different ClassLoaders to be co-mingled. This is a problem if, for example, a web application is undeployed as some of the Loggers being released may be associated with a Class in a parent ClassLoader, which will generally have negative consequences. The main downside to this ContextSelector is that Configuration is more challenging. This ContextSelector should not be used with a Servlet Filter such as the Log4jServletFilter.

Field Summary

Fields

Modifier and Type	Field and Description
protected static ConcurrentMap<String,AtomicReference<WeakReference<LoggerContext>>>	CONTEXT_MAP
protected static StatusLogger	LOGGER

Fields inherited from interface org.apache.logging.log4j.core.selector.ContextSelector

DEFAULT_STOP_TIMEOUT

Constructor Summary

Constructors

Constructor and Description
ClassLoaderContextSelector()

Method Summary

Modifier and Type	Method and Description
void	contextShutdown(LoggerContext loggerContext)
protected LoggerContext	createContext(String name, URI configLocation)
protected String	defaultContextName()
LoggerContext	getContext(String fqcn, ClassLoader loader, boolean currentContext) Returns the LoggerContext.
LoggerContext	getContext(String fqcn, ClassLoader loader, boolean currentContext, URI configLocation) Returns the LoggerContext.
LoggerContext	getContext(String fqcn, ClassLoader loader, Map.Entry<String,Object> entry, boolean currentContext, URI configLocation) Returns the LoggerContext.
protected LoggerContext	getDefault()
List<LoggerContext>	getLoggerContexts() Returns a List of all the available LoggerContexts.
boolean	hasContext(String fqcn, ClassLoader loader, boolean currentContext) Checks to see if a LoggerContext is installed.
boolean	isClassLoaderDependent() Determines whether or not this ContextSelector depends on the callers classloader.
void	removeContext(LoggerContext context) Remove any references to the LoggerContext.
void	shutdown(String fqcn, ClassLoader loader, boolean currentContext, boolean allContexts) Shuts down the LoggerContext.
protected String	toContextMapKey(ClassLoader loader)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.logging.log4j.core.selector.ContextSelector

getContext

Field Detail

LOGGER

protected static final StatusLogger LOGGER

CONTEXT_MAP

protected static final ConcurrentMap<String,AtomicReference<WeakReference<LoggerContext>>> CONTEXT_MAP

Constructor Detail

ClassLoaderContextSelector

public ClassLoaderContextSelector()

Method Detail

shutdown

public void shutdown(String fqcn,
                     ClassLoader loader,
                     boolean currentContext,
                     boolean allContexts)

Description copied from interface: ContextSelector

Shuts down the LoggerContext.

Specified by:

shutdown in interface ContextSelector

Parameters:

fqcn - The fully qualified class name of the caller.

loader - The ClassLoader to use or null.

currentContext - If true returns the current Context, if false returns the Context appropriate

allContexts - if true all LoggerContexts that can be located will be shutdown.

contextShutdown

public void contextShutdown(LoggerContext loggerContext)

Specified by:

contextShutdown in interface LoggerContextShutdownAware

hasContext

public boolean hasContext(String fqcn,
                          ClassLoader loader,
                          boolean currentContext)

Description copied from interface: ContextSelector

Checks to see if a LoggerContext is installed. The default implementation returns false.

Specified by:

hasContext in interface ContextSelector

Parameters:

fqcn - The fully qualified class name of the caller.

loader - The ClassLoader to use or null.

currentContext - If true returns the current Context, if false returns the Context appropriate for the caller if a more appropriate Context can be determined.

Returns:

true if a LoggerContext has been installed, false otherwise.

getContext

public LoggerContext getContext(String fqcn,
                                ClassLoader loader,
                                boolean currentContext)

Description copied from interface: ContextSelector

Returns the LoggerContext.

Specified by:

getContext in interface ContextSelector

Parameters:

fqcn - The fully qualified class name of the caller.

loader - ClassLoader to use or null.

currentContext - If true returns the current Context, if false returns the Context appropriate for the caller if a more appropriate Context can be determined.

Returns:

The LoggerContext.

getContext

public LoggerContext getContext(String fqcn,
                                ClassLoader loader,
                                boolean currentContext,
                                URI configLocation)

Description copied from interface: ContextSelector

Returns the LoggerContext.

Specified by:

getContext in interface ContextSelector

Parameters:

fqcn - The fully qualified class name of the caller.

loader - ClassLoader to use or null.

currentContext - If true returns the current Context, if false returns the Context appropriate for the caller if a more appropriate Context can be determined.

configLocation - The location of the configuration for the LoggerContext.

Returns:

The LoggerContext.

getContext

public LoggerContext getContext(String fqcn,
                                ClassLoader loader,
                                Map.Entry<String,Object> entry,
                                boolean currentContext,
                                URI configLocation)

Description copied from interface: ContextSelector

Returns the LoggerContext.

Specified by:

getContext in interface ContextSelector

Parameters:

fqcn - The fully qualified class name of the caller.

loader - ClassLoader to use or null.

currentContext - If true returns the current Context, if false returns the Context appropriate for the caller if a more appropriate Context can be determined.

configLocation - The location of the configuration for the LoggerContext.

Returns:

The LoggerContext.

removeContext

public void removeContext(LoggerContext context)

Description copied from interface: ContextSelector

Remove any references to the LoggerContext.

Specified by:

removeContext in interface ContextSelector

Parameters:

context - The context to remove.

isClassLoaderDependent

public boolean isClassLoaderDependent()

Description copied from interface: ContextSelector

Determines whether or not this ContextSelector depends on the callers classloader. This method should be overridden by implementations, however a default method is provided which always returns true to preserve the old behavior.

Specified by:

isClassLoaderDependent in interface ContextSelector

Returns:

true if the class loader is required.

getLoggerContexts

public List<LoggerContext> getLoggerContexts()

Description copied from interface: ContextSelector

Returns a List of all the available LoggerContexts.

Specified by:

getLoggerContexts in interface ContextSelector

Returns:

The List of LoggerContexts.

createContext

protected LoggerContext createContext(String name,
                                      URI configLocation)

toContextMapKey

protected String toContextMapKey(ClassLoader loader)

getDefault

protected LoggerContext getDefault()

defaultContextName

protected String defaultContextName()