com.interface21.web.util
Class Log4jConfigListener

java.lang.Object
  |
  +--com.interface21.web.util.Log4jConfigListener

All Implemented Interfaces:

java.util.EventListener, javax.servlet.ServletContextListener

public class Log4jConfigListener

extends java.lang.Object

implements javax.servlet.ServletContextListener

Listener that performs custom Log4J initialization, supporting 2 init parameters at the servlet context level (i.e. context-param in web.xml):

• "log4jLocation": name of the Log4J config file (relative to the web application root directory, e.g. "WEB-INF/log4j.properties");
• "log4jRefreshInterval": interval between config file refresh* checks.

Note: This listener should be placed before ContextLoaderListener in web.xml, at least when used for Log4J.

Note: Sets the web app root system property implicitly, for ${key} substitutions within log file locations in the Log4J config file. The default system property key is "webapp.root". Example, using context-param "webAppRootKey" = "demo.root": log4j.appender.myfile.File=${demo.root}/WEB-INF/demo.log

WARNING: Some containers like Tomcat do NOT keep system properties separate per web app. You have to use unique "webAppRootKey" context-params per web app then, to avoid clashes. Other containers like Resin do isolate each web app's system properties: Here you can use the default key (i.e. no "webAppRootKey" context-param at all) without worrying.

Since:

13.03.2003

Author:

Juergen Hoeller

See Also:

Log4jConfigurer, WebAppRootListener

Field Summary

static java.lang.String	CONFIG_LOCATION_PARAM Parameter specifying the location of the Log4J config file.
static java.lang.String	REFRESH_INTERVAL_PARAM Parameter specifying the refresh interval for checking the Log4J config file.

Constructor Summary

Log4jConfigListener()

Method Summary

void	contextDestroyed(javax.servlet.ServletContextEvent event)
void	contextInitialized(javax.servlet.ServletContextEvent event)

Methods inherited from class java.lang.Object

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

Field Detail

CONFIG_LOCATION_PARAM

public static final java.lang.String CONFIG_LOCATION_PARAM

Parameter specifying the location of the Log4J config file.

REFRESH_INTERVAL_PARAM

public static final java.lang.String REFRESH_INTERVAL_PARAM

Parameter specifying the refresh interval for checking the Log4J config file.

Constructor Detail

Log4jConfigListener

public Log4jConfigListener()

Method Detail

contextInitialized

public void contextInitialized(javax.servlet.ServletContextEvent event)

Specified by:

contextInitialized in interface javax.servlet.ServletContextListener

contextDestroyed

public void contextDestroyed(javax.servlet.ServletContextEvent event)

Specified by:

contextDestroyed in interface javax.servlet.ServletContextListener