public class WebAppRootListener extends java.lang.Object implements ServletContextListener
Can be used for toolkits that support substitution with system properties (i.e. System.getProperty values), like log4j's "${key}" syntax within log file locations.
Note: This listener should be placed before ContextLoaderListener in web.xml
,
at least when used for log4j. Log4jConfigListener sets the system property
implicitly, so there's no need for this listener in addition to it.
WARNING: Some containers, e.g. 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.
WARNING: The WAR file containing the web application needs to be expanded to allow for setting the web app root system property. This is by default not the case when a WAR file gets deployed to WebLogic, for example. Do not use this listener in such an environment!
WebUtils.setWebAppRootSystemProperty(javax.servlet.ServletContext)
,
System.getProperty(java.lang.String)
Constructor and Description |
---|
WebAppRootListener() |
Modifier and Type | Method and Description |
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void |
contextDestroyed(ServletContextEvent event) |
void |
contextInitialized(ServletContextEvent event) |
public void contextInitialized(ServletContextEvent event)
contextInitialized
in interface ServletContextListener
public void contextDestroyed(ServletContextEvent event)
contextDestroyed
in interface ServletContextListener