org.wicketstuff.logback

Class LogbackConfigListener

java.lang.Object

org.wicketstuff.logback.LogbackConfigListener

All Implemented Interfaces:

EventListener, javax.servlet.ServletContextListener

public class LogbackConfigListener
extends Object
implements javax.servlet.ServletContextListener

ServletContextListener that can be used in web applications to define the location of the logback configuration and optionally to inject the context path into the properties of logback

Should be the first listener to configure logback before using it. Location is defined in the logbackConfigLocation context param. Snippet from web.xml:

 
 <!-- mandatory, sets the custom config location -->
 <context-param>
     <param-name>logbackConfigLocation</param-name>
     <param-value>/WEB-INF/log-sc.xml</param-value>
 </context-param>
 
 <!-- optional, needed if config wants to use the context path -->
 <context-param>
     <param-name>logbackConfigContextPathKey</param-name>
     <param-value>contextPath</param-value>
 </context-param>
 
 <!-- mandatory, applies custom config location based on the value of
      logbackConfigLocation -->
 <listener>
     <listener-class>org.wicketstuff.logback.LogbackConfigListener</listener-class>
 </listener>
 
 
 

The above means that logback will be configured using the /WEB-INF/log-sc.xml servlet context resource and ${contextPath} can be used in the logback config as a placeholder for the webapp's context path.

Placeholders (ex: ${user.home}) in logbackConfigLocation are supported. Location examples:
/WEB-INF/log-sc.xml (starts with '/') -> loaded from servlet context
classpath:foo/log-cp.xml (starts with "classpath:") -> loaded from classpath
file:/D:/log-absfile.xml (is a valid url) -> loaded as url
D:/log-absfile.xml (is an absolute file path) -> loaded as absolute file
log-relfile.xml (is a relative file path) -> loaded as file relative to the servlet container working directory

Author:

akiraly

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONFIG_CONTEXT_PATH_KEY_PARAM Context param name for logback context path property name.
static String	CONFIG_LOCATION_PARAM Context param name for location.
static String	CONTEXT_PATH_ROOT_VAL Injected name for root context path ("ROOT").
static String	LOCATION_PREFIX_CLASSPATH Prefix for classpath urls.

Constructor Summary

Constructors

Constructor and Description
LogbackConfigListener()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	applyConfigLocation(javax.servlet.ServletContext sc, ch.qos.logback.classic.LoggerContext lc) Configures logback with the custom config location specified in the web.xml.
protected void	configureConfig(javax.servlet.ServletContext sc, ch.qos.logback.classic.LoggerContext lc, URL location, String contextPathKey) Reconfigures logback to use the config from the specified url.
void	contextDestroyed(javax.servlet.ServletContextEvent sce)
void	contextInitialized(javax.servlet.ServletContextEvent sce)
protected String	getContextPath(javax.servlet.ServletContext sc) Returns a normalized context path for the webapp.
protected URL	toUrl(javax.servlet.ServletContext sc, String location) Converts the passed in location String to an URL.

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 String CONFIG_LOCATION_PARAM

Context param name for location.

See Also:

Constant Field Values

CONFIG_CONTEXT_PATH_KEY_PARAM

public static final String CONFIG_CONTEXT_PATH_KEY_PARAM

Context param name for logback context path property name.

See Also:

Constant Field Values

CONTEXT_PATH_ROOT_VAL

public static final String CONTEXT_PATH_ROOT_VAL

Injected name for root context path ("ROOT").

See Also:

Constant Field Values

LOCATION_PREFIX_CLASSPATH

public static final String LOCATION_PREFIX_CLASSPATH

Prefix for classpath urls.

See Also:

Constant Field Values

Constructor Detail

LogbackConfigListener

public LogbackConfigListener()

Method Detail

contextInitialized

public void contextInitialized(javax.servlet.ServletContextEvent sce)

Specified by:

contextInitialized in interface javax.servlet.ServletContextListener

applyConfigLocation

protected void applyConfigLocation(javax.servlet.ServletContext sc,
                       ch.qos.logback.classic.LoggerContext lc)

Configures logback with the custom config location specified in the web.xml.

Parameters:

sc - represents the webapp, not null

lc - logback context to be configured, not null

configureConfig

protected void configureConfig(javax.servlet.ServletContext sc,
                   ch.qos.logback.classic.LoggerContext lc,
                   URL location,
                   String contextPathKey)

Reconfigures logback to use the config from the specified url.

Parameters:

sc - represents the webapp, not null

lc - logback context to be configured, not null

location - point to the logback config, not null

contextPathKey - nullable, a not null value is the property name under which the webapp context path is stored

getContextPath

protected String getContextPath(javax.servlet.ServletContext sc)

Returns a normalized context path for the webapp. For the root webapp (context path ""), CONTEXT_PATH_ROOT_VAL is returned.

Parameters:

sc - represents the webapp, not null

Returns:

normalized context path, not null, not empty

toUrl

protected URL toUrl(javax.servlet.ServletContext sc,
        String location)

Converts the passed in location String to an URL.

Parameters:

sc - represents the webapp, not null

location - holding the config resource location as string, not null

Returns:

the URL representation of location or null if conversion was not possible

contextDestroyed

public void contextDestroyed(javax.servlet.ServletContextEvent sce)

Specified by:

contextDestroyed in interface javax.servlet.ServletContextListener