/**
* Initialize logback, including setting the web app root system property.
*
* @param servletContext the current ServletContext
* @see WebUtils#setWebAppRootSystemProperty
*/
public static void initLogging(ServletContext servletContext) {
// Expose the web app root system property.
if (exposeWebAppRoot(servletContext)) {
WebUtils.setWebAppRootSystemProperty(servletContext);
}
// Only perform custom logback initialization in case of a config file.
String location = servletContext.getInitParameter(CONFIG_LOCATION_PARAM);
if (location != null) {
// Perform actual logback initialization; else rely on logback's default initialization.
try {
// Return a URL (e.g. "classpath:" or "file:") as-is;
// consider a plain file path as relative to the web application root directory.
if (!ResourceUtils.isUrl(location)) {
// Resolve system property placeholders before resolving real path.
location = SystemPropertyUtils.resolvePlaceholders(location);
location = WebUtils.getRealPath(servletContext, location);
}
// Write log message to server log.
servletContext.log("Initializing logback from [" + location + "]");
// Initialize without refresh check, i.e. without logback's watchdog thread.
LogbackConfigurer.initLogging(location);
} catch (FileNotFoundException ex) {
throw new IllegalArgumentException(
"Invalid 'logbackConfigLocation' parameter: " + ex.getMessage());
}
}
}
