in src/main/java/org/apache/log4j/LogManager.java [80:139]
static {
// By default we use a DefaultRepositorySelector which always returns 'h'.
Hierarchy h = new Hierarchy(new RootLogger((Level) Level.DEBUG));
repositorySelector = new DefaultRepositorySelector(h);
/** Search for the properties file log4j.properties in the CLASSPATH. */
String override =OptionConverter.getSystemProperty(DEFAULT_INIT_OVERRIDE_KEY,
null);
// if there is no default init override, then get the resource
// specified by the user or the default config file.
if(override == null || "false".equalsIgnoreCase(override)) {
String configurationOptionStr = OptionConverter.getSystemProperty(
DEFAULT_CONFIGURATION_KEY,
null);
String configuratorClassName = OptionConverter.getSystemProperty(
CONFIGURATOR_CLASS_KEY,
null);
URL url = null;
// if the user has not specified the log4j.configuration
// property, we search first for the file "log4j.xml" and then
// "log4j.properties"
if(configurationOptionStr == null) {
url = Loader.getResource(DEFAULT_XML_CONFIGURATION_FILE);
if(url == null) {
url = Loader.getResource(DEFAULT_CONFIGURATION_FILE);
}
} else {
try {
url = new URL(configurationOptionStr);
} catch (MalformedURLException ex) {
// so, resource is not a URL:
// attempt to get the resource from the class path
url = Loader.getResource(configurationOptionStr);
}
}
// If we have a non-null url, then delegate the rest of the
// configuration to the OptionConverter.selectAndConfigure
// method.
if(url != null) {
LogLog.debug("Using URL ["+url+"] for automatic log4j configuration.");
try {
OptionConverter.selectAndConfigure(url, configuratorClassName,
LogManager.getLoggerRepository());
} catch (NoClassDefFoundError e) {
LogLog.warn("Error during default initialization", e);
}
} else {
LogLog.debug("Could not find resource: ["+configurationOptionStr+"].");
}
} else {
LogLog.debug("Default initialization of overridden by " +
DEFAULT_INIT_OVERRIDE_KEY + "property.");
}
}