org.apache.avalon.excalibur.logger

Class AbstractLoggerManager

java.lang.Object

org.apache.avalon.excalibur.logger.AbstractLoggerManager

All Implemented Interfaces:

LoggerManager, org.apache.avalon.framework.logger.LogEnabled

Direct Known Subclasses:

Log4JLoggerManager, LogKitLoggerManager

public abstract class AbstractLoggerManager
extends java.lang.Object
implements org.apache.avalon.framework.logger.LogEnabled, LoggerManager

This abstract class implements LogEnabled. A derived class is expected to obtain a logger via getLogger() and live with it. The Logger supplied via enableLogging will be used both as the "initial" and as the "fallback" logger.

• "initial" means that until a call to start() the messages logger via getLogger().xxx() will go to this logger
• "fallback" means that if after a successfull start a recursive invocation of getLogger().xxx() will be detected the message will be logged via the initial logger as a fallback.

See LoggerSwitch for more details.

Since:

4.0

Version:

CVS $Revision: 1.5 $ $Date: 2004/03/10 13:54:49 $

Author:

Avalon Development Team

Field Summary

Fields

Modifier and Type	Field and Description
private org.apache.avalon.framework.logger.Logger	m_defaultLoggerOverride The logger used to be returned from getDefaultLogger() and getLoggerForCategory(""), if one has been forcibly set via a constructor.
private boolean	m_enableLoggingInvoked safeguards against double enableLogging() invocation.
private org.apache.avalon.framework.logger.Logger	m_logger Always equals to m_switch.get()
protected java.util.Map	m_loggers Map for name to logger mapping.
protected java.lang.String	m_prefix The root logger to configure
private boolean	m_startInvoked safeguards against double start() invocation.
private LoggerSwitch	m_switch The object that wraps a swithing logger.
private java.lang.String	m_switchTo category we should switch our own loggin to on start().

Fields inherited from interface org.apache.avalon.excalibur.logger.LoggerManager

ROLE

Constructor Summary

Constructors

Constructor and Description
AbstractLoggerManager(java.lang.String prefix, java.lang.String switchTo, org.apache.avalon.framework.logger.Logger defaultLoggerOverride) Initializes AbstractLoggerManager.

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract org.apache.avalon.framework.logger.Logger	doGetLoggerForCategory(java.lang.String fullCategoryName) Actually create a logger wrapping underlying logger backed implementation for a give category.
void	enableLogging(org.apache.avalon.framework.logger.Logger fallbackLogger) Accept the logger we shall use as the initial and the fallback logger.
org.apache.avalon.framework.logger.Logger	getDefaultLogger() Retruns the logger for the "" category.
protected org.apache.avalon.framework.logger.Logger	getLogger() Derived LoggerManager implementations should obtain a logger to log their own messages via this call.
org.apache.avalon.framework.logger.Logger	getLoggerForCategory(java.lang.String categoryName) Retrieves a Logger from a category name.
void	start() Get a logger from ourselves and pass it to m_switch.
void	stop() Startable.stop() empty implementation.

Methods inherited from class java.lang.Object

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

Field Detail

m_loggers

protected final java.util.Map m_loggers

Map for name to logger mapping. This instance variable is protected (not privated) so that it may be pre-filled at configuration stage.

m_prefix

protected java.lang.String m_prefix

The root logger to configure

m_switch

private LoggerSwitch m_switch

The object that wraps a swithing logger. The switching logger itself for security reasons has no methods of controlling it, but its wrapping object has.

m_logger

private org.apache.avalon.framework.logger.Logger m_logger

Always equals to m_switch.get()

m_switchTo

private java.lang.String m_switchTo

category we should switch our own loggin to on start().

m_enableLoggingInvoked

private boolean m_enableLoggingInvoked

safeguards against double enableLogging() invocation.

m_startInvoked

private boolean m_startInvoked

safeguards against double start() invocation.

m_defaultLoggerOverride

private final org.apache.avalon.framework.logger.Logger m_defaultLoggerOverride

The logger used to be returned from getDefaultLogger() and getLoggerForCategory(""), if one has been forcibly set via a constructor.

Constructor Detail

AbstractLoggerManager

public AbstractLoggerManager(java.lang.String prefix,
                     java.lang.String switchTo,
                     org.apache.avalon.framework.logger.Logger defaultLoggerOverride)

Initializes AbstractLoggerManager.

Parameters:

prefix - the prefix to prepended to the category name on each invocation of getLoggerForCategory before passing the category name on to the underlying logging system (currently LogKit or Log4J).

switchTo - fuel for the start() method; if null start() will do nothing; if empty start() will switch to getLoggerForCategory("").

Method Detail

getLogger

protected org.apache.avalon.framework.logger.Logger getLogger()

Derived LoggerManager implementations should obtain a logger to log their own messages via this call. It is also safe to log messages about logging failures via this logger as it safeguards internally gainst recursion.

enableLogging

public void enableLogging(org.apache.avalon.framework.logger.Logger fallbackLogger)

Accept the logger we shall use as the initial and the fallback logger.

Specified by:

enableLogging in interface org.apache.avalon.framework.logger.LogEnabled

start

public void start()

Get a logger from ourselves and pass it to m_switch.

stop

public void stop()

Startable.stop() empty implementation.

getDefaultLogger

public final org.apache.avalon.framework.logger.Logger getDefaultLogger()

Retruns the logger for the "" category.

Specified by:

getDefaultLogger in interface LoggerManager

doGetLoggerForCategory

protected abstract org.apache.avalon.framework.logger.Logger doGetLoggerForCategory(java.lang.String fullCategoryName)

Actually create a logger wrapping underlying logger backed implementation for a give category. Bypasses the caching. Derived LoggerManager implementations should provide an implementation of this method.

getLoggerForCategory

public final org.apache.avalon.framework.logger.Logger getLoggerForCategory(java.lang.String categoryName)

Retrieves a Logger from a category name. Usually the category name refers to a configuration attribute name. If this LogKitManager does not have the match the default Logger will be returned and a warning is issued.

Specified by:

getLoggerForCategory in interface LoggerManager