Package org.jboss.logmanager

Class LogContext

java.lang.Object

org.jboss.logmanager.LogContext

All Implemented Interfaces:

AutoCloseable

public final class LogContext
extends Object
implements AutoCloseable

A logging context, for producing isolated logging environments.

Field Summary

Fields

Modifier and Type	Field	Description
static LogContextSelector	DEFAULT_LOG_CONTEXT_SELECTOR	The default log context selector, which always returns the system log context.

Method Summary

Modifier and Type	Method	Description
void	addCloseHandler(AutoCloseable closeHandler)	Adds a handler invoked during the close of this log context.
<V> V	attach(Logger.AttachmentKey<V> key, V value)	Attach an object to this log context under a given key.
<V> V	attachIfAbsent(Logger.AttachmentKey<V> key, V value)	Attach an object to this log context under a given key, if such an attachment does not already exist.
void	close()
static LogContext	create()	Create a new log context.
static LogContext	create(boolean strong)	Create a new log context.
static LogContext	create(boolean strong, LogContextInitializer initializer)	Create a new log context.
static LogContext	create(LogContextInitializer initializer)	Create a new log context.
<V> V	detach(Logger.AttachmentKey<V> key)	Remove an attachment.
<V> V	getAttachment(String loggerName, Logger.AttachmentKey<V> key)	Get a logger attachment for a logger name, if it exists.
<V> V	getAttachment(Logger.AttachmentKey<V> key)	Get the attachment value for a given key, or null if there is no such attachment.
Set<AutoCloseable>	getCloseHandlers()	Gets the current close handlers associated with this log context.
Level	getLevelForName(String name)	Get the level for a name.
static LogContext	getLogContext()	Get the currently active log context.
static LogContextSelector	getLogContextSelector()	Returns the currently set log context selector.
Logger	getLogger(String name)	Get a logger with the given name from this logging context.
Logger	getLoggerIfExists(String name)	Get a logger with the given name from this logging context, if a logger node exists at that location.
Enumeration<String>	getLoggerNames()	Returns an enumeration of the logger names that have been created.
static LogContext	getSystemLogContext()	Get the system log context.
void	registerLevel(Level level)	Register a level instance with this log context.
void	registerLevel(Level level, boolean strong)	Register a level instance with this log context.
void	setCloseHandlers(Collection<AutoCloseable> closeHandlers)	Clears any current close handlers associated with log context, then adds the handlers to be invoked during the close of this log context.
static void	setLogContextSelector(LogContextSelector newSelector)	Set a new log context selector.
void	unregisterLevel(Level level)	Unregister a previously registered level.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_LOG_CONTEXT_SELECTOR

public static final LogContextSelector DEFAULT_LOG_CONTEXT_SELECTOR

The default log context selector, which always returns the system log context.

Method Detail

create

public static LogContext create(boolean strong)

Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.

Parameters:

strong - true if the context should use strong references, false to use (default) weak references for automatic logger GC

Returns:

a new log context

create

public static LogContext create(boolean strong,
                                LogContextInitializer initializer)

Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.

Parameters:

strong - true if the context should use strong references, false to use (default) weak references for automatic logger GC

initializer - the log context initializer to use (must not be null)

Returns:

a new log context

create

public static LogContext create()

Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.

Returns:

a new log context

create

public static LogContext create(LogContextInitializer initializer)

Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.

Parameters:

initializer - the log context initializer to use (must not be null)

Returns:

a new log context

getAttachment

public <V> V getAttachment(Logger.AttachmentKey<V> key)

Get the attachment value for a given key, or null if there is no such attachment. Log context attachments are placed on the root logger and can also be accessed there.

Type Parameters:

V - the attachment value type

Parameters:

key - the key

Returns:

the attachment, or null if there is none for this key

attach

public <V> V attach(Logger.AttachmentKey<V> key,
                    V value)
             throws SecurityException

Attach an object to this log context under a given key. A strong reference is maintained to the key and value for as long as this log context exists. Log context attachments are placed on the root logger and can also be accessed there.

Type Parameters:

V - the attachment value type

Parameters:

key - the attachment key

value - the attachment value

Returns:

the old attachment, if there was one

Throws:

SecurityException - if a security manager exists and if the caller does not have LoggingPermission(control)

IllegalArgumentException - if the attachment cannot be added because the maximum has been reached

attachIfAbsent

public <V> V attachIfAbsent(Logger.AttachmentKey<V> key,
                            V value)
                     throws SecurityException

Attach an object to this log context under a given key, if such an attachment does not already exist. A strong reference is maintained to the key and value for as long as this log context exists. Log context attachments are placed on the root logger and can also be accessed there.

Type Parameters:

V - the attachment value type

Parameters:

key - the attachment key

value - the attachment value

Returns:

the current attachment, if there is one, or null if the value was successfully attached

Throws:

SecurityException - if a security manager exists and if the caller does not have LoggingPermission(control)

IllegalArgumentException - if the attachment cannot be added because the maximum has been reached

detach

public <V> V detach(Logger.AttachmentKey<V> key)
             throws SecurityException

Remove an attachment. Log context attachments are placed on the root logger and can also be accessed there.

Type Parameters:

V - the attachment value type

Parameters:

key - the attachment key

Returns:

the old value, or null if there was none

Throws:

SecurityException - if a security manager exists and if the caller does not have LoggingPermission(control)

getLogger

public Logger getLogger(String name)

Get a logger with the given name from this logging context.

Parameters:

name - the logger name

Returns:

the logger instance

See Also:

LogManager.getLogger(String)

getLoggerIfExists

public Logger getLoggerIfExists(String name)

Get a logger with the given name from this logging context, if a logger node exists at that location.

Parameters:

name - the logger name

Returns:

the logger instance, or null if no such logger node exists

getAttachment

public <V> V getAttachment(String loggerName,
                           Logger.AttachmentKey<V> key)

Get a logger attachment for a logger name, if it exists.

Type Parameters:

V - the attachment value type

Parameters:

loggerName - the logger name

key - the attachment key

Returns:

the attachment or null if the logger or the attachment does not exist

getLevelForName

public Level getLevelForName(String name)
                      throws IllegalArgumentException

Get the level for a name.

Parameters:

name - the name

Returns:

the level

Throws:

IllegalArgumentException - if the name is not known

registerLevel

public void registerLevel(Level level)

Register a level instance with this log context. The level can then be looked up by name. Only a weak reference to the level instance will be kept. Any previous level registration for the given level's name will be overwritten.

Parameters:

level - the level to register

registerLevel

public void registerLevel(Level level,
                          boolean strong)

Register a level instance with this log context. The level can then be looked up by name. Any previous level registration for the given level's name will be overwritten.

Parameters:

level - the level to register

strong - true to strongly reference the level, or false to weakly reference it

unregisterLevel

public void unregisterLevel(Level level)

Unregister a previously registered level. Log levels that are not registered may still be used, they just will not be findable by name.

Parameters:

level - the level to unregister

getSystemLogContext

public static LogContext getSystemLogContext()

Get the system log context.

Returns:

the system log context

getLogContext

public static LogContext getLogContext()

Get the currently active log context.

Returns:

the currently active log context

setLogContextSelector

public static void setLogContextSelector(LogContextSelector newSelector)

Set a new log context selector. If a security manager is installed, the caller must have the "setLogContextSelector" RuntimePermission to invoke this method.

Parameters:

newSelector - the new selector.

getLogContextSelector

public static LogContextSelector getLogContextSelector()

Returns the currently set log context selector.

Returns:

the log context selector

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception

getLoggerNames

public Enumeration<String> getLoggerNames()

Returns an enumeration of the logger names that have been created. This does not return names of loggers that may have been garbage collected. Logger names added after the enumeration has been retrieved may also be added to the enumeration.

Returns:

an enumeration of the logger names

See Also:

LogManager.getLoggerNames()

addCloseHandler

public void addCloseHandler(AutoCloseable closeHandler)

Adds a handler invoked during the close of this log context. The close handlers will be invoked in the order they are added.

The loggers associated with this context will always be closed.

Parameters:

closeHandler - the close handler to use

getCloseHandlers

public Set<AutoCloseable> getCloseHandlers()

Gets the current close handlers associated with this log context.

Returns:

the current close handlers

setCloseHandlers

public void setCloseHandlers(Collection<AutoCloseable> closeHandlers)

Clears any current close handlers associated with log context, then adds the handlers to be invoked during the close of this log context. The close handlers will be invoked in the order they are added.

The loggers associated with this context will always be closed.

Parameters:

closeHandlers - the close handlers to use