package org.apache.log4j;
import org.apache.log4j.DefaultCategoryFactory;
import org.apache.log4j.config.PropertySetter;
//import org.apache.log4j.config.PropertySetterException;
import org.apache.log4j.spi.OptionHandler;
import org.apache.log4j.spi.Configurator;
import org.apache.log4j.spi.LoggerFactory;
import org.apache.log4j.spi.LoggerRepository;
import org.apache.log4j.spi.RendererSupport;
import org.apache.log4j.or.RendererMap;
import org.apache.log4j.helpers.LogLog;
import org.apache.log4j.helpers.OptionConverter;
import org.apache.log4j.helpers.FileWatchdog;
import java.util.Enumeration;
import java.util.Properties;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.StringTokenizer;
import java.util.Hashtable;
/**
Allows the configuration of log4j from an external file. See
{@link #doConfigure(String, LoggerRepository)} for the
expected format.
It is sometimes useful to see how log4j is reading configuration
files. You can enable log4j internal logging by defining the
log4j.debug variable.
As of log4j version 0.8.5, at class initialization time class,
the file log4j.properties will be searched from the search
path used to load classes. If the file can be found, then it will
be fed to the {@link PropertyConfigurator#configure(java.net.URL)}
method.
The PropertyConfigurator
does not handle the
advanced configuration features supported by the {@link
org.apache.log4j.xml.DOMConfigurator DOMConfigurator} such as
support for {@link org.apache.log4j.spi.Filter Filters}, custom
{@link org.apache.log4j.spi.ErrorHandler ErrorHandlers}, nested
appenders such as the {@link org.apache.log4j.AsyncAppender
AsyncAppender}, etc.
All option values admit variable substitution. The
syntax of variable substitution is similar to that of Unix
shells. The string between an opening "${" and
closing "}" is interpreted as a key. The value of
the substituted variable can be defined as a system property or in
the configuration file itself. The value of the key is first
searched in the system properties, and if not found there, it is
then searched in the configuration file being parsed. The
corresponding value replaces the ${variableName} sequence. For
example, if java.home
system property is set to
/home/xyz
, then every occurrence of the sequence
${java.home}
will be interpreted as
/home/xyz
.
@author Ceki Gülcü
@author Anders Kristensen
@since 0.8.1 */
public class PropertyConfigurator implements Configurator {
/**
Used internally to keep track of configured appenders.
*/
protected Hashtable registry = new Hashtable(11);
protected LoggerFactory loggerFactory = new DefaultCategoryFactory();
static final String CATEGORY_PREFIX = "log4j.category.";
static final String LOGGER_PREFIX = "log4j.logger.";
static final String FACTORY_PREFIX = "log4j.factory";
static final String ADDITIVITY_PREFIX = "log4j.additivity.";
static final String ROOT_CATEGORY_PREFIX = "log4j.rootCategory";
static final String ROOT_LOGGER_PREFIX = "log4j.rootLogger";
static final String APPENDER_PREFIX = "log4j.appender.";
static final String RENDERER_PREFIX = "log4j.renderer.";
static final String THRESHOLD_PREFIX = "log4j.threshold";
/** Key for specifying the {@link org.apache.log4j.spi.LoggerFactory
LoggerFactory}. Currently set to "log4j.loggerFactory
". */
public static final String LOGGER_FACTORY_KEY = "log4j.loggerFactory";
static final private String INTERNAL_ROOT_NAME = "root";
/**
Read configuration from a file. The existing configuration is
not cleared nor reset. If you require a different behavior,
then call {@link LogManager#resetConfiguration
resetConfiguration} method before calling
doConfigure
.
The configuration file consists of statements in the format
key=value
. The syntax of different configuration
elements are discussed below.
Repository-wide threshold
The repository-wide threshold filters logging requests by level
regardless of logger. The syntax is:
log4j.threshold=[level]
The level value can consist of the string values OFF, FATAL,
ERROR, WARN, INFO, DEBUG, ALL or a custom level value. A
custom level value can be specified in the form
level#classname. By default the repository-wide threshold is set
to the lowest possible value, namely the level ALL
.
Appender configuration
Appender configuration syntax is:
# For appender named appenderName, set its class.
# Note: The appender name can contain dots.
log4j.appender.appenderName=fully.qualified.name.of.appender.class
# Set appender specific options.
log4j.appender.appenderName.option1=value1
...
log4j.appender.appenderName.optionN=valueN
For each named appender you can configure its {@link Layout}. The
syntax for configuring an appender's layout is:
log4j.appender.appenderName.layout=fully.qualified.name.of.layout.class
log4j.appender.appenderName.layout.option1=value1
....
log4j.appender.appenderName.layout.optionN=valueN
Configuring loggers
The syntax for configuring the root logger is:
log4j.rootLogger=[level], appenderName, appenderName, ...
This syntax means that an optional level can be
supplied followed by appender names separated by commas.
The level value can consist of the string values OFF, FATAL,
ERROR, WARN, INFO, DEBUG, ALL or a custom level value. A
custom level value can be specified in the form
level#classname
.
If a level value is specified, then the root level is set
to the corresponding level. If no level value is specified,
then the root level remains untouched.
The root logger can be assigned multiple appenders.
Each appenderName (separated by commas) will be added to
the root logger. The named appender is defined using the
appender syntax defined above.
For non-root categories the syntax is almost the same:
log4j.logger.logger_name=[level|INHERITED|NULL], appenderName, appenderName, ...
The meaning of the optional level value is discussed above
in relation to the root logger. In addition however, the value
INHERITED can be specified meaning that the named logger should
inherit its level from the logger hierarchy.
If no level value is supplied, then the level of the
named logger remains untouched.
By default categories inherit their level from the
hierarchy. However, if you set the level of a logger and later
decide that that logger should inherit its level, then you should
specify INHERITED as the value for the level value. NULL is a
synonym for INHERITED.
Similar to the root logger syntax, each appenderName
(separated by commas) will be attached to the named logger.
See the appender
additivity rule in the user manual for the meaning of the
additivity
flag.
ObjectRenderers
You can customize the way message objects of a given type are
converted to String before being logged. This is done by
specifying an {@link org.apache.log4j.or.ObjectRenderer ObjectRenderer}
for the object type would like to customize.
The syntax is:
log4j.renderer.fully.qualified.name.of.rendered.class=fully.qualified.name.of.rendering.class
As in,
log4j.renderer.my.Fruit=my.FruitRenderer
Logger Factories
The usage of custom logger factories is discouraged and no longer
documented.
Example
An example configuration is given below. Other configuration
file examples are given in the examples
folder.
# Set options for appender named "A1".
# Appender "A1" will be a SyslogAppender
log4j.appender.A1=org.apache.log4j.net.SyslogAppender
# The syslog daemon resides on www.abc.net
log4j.appender.A1.SyslogHost=www.abc.net
# A1's layout is a PatternLayout, using the conversion pattern
# %r %-5p %c{2} %M.%L %x - %m\n. Thus, the log output will
# include # the relative time since the start of the application in
# milliseconds, followed by the level of the log request,
# followed by the two rightmost components of the logger name,
# followed by the callers method name, followed by the line number,
# the nested disgnostic context and finally the message itself.
# Refer to the documentation of {@link PatternLayout} for further information
# on the syntax of the ConversionPattern key.
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r %-5p %c{2} %M.%L %x - %m\n
# Set options for appender named "A2"
# A2 should be a RollingFileAppender, with maximum file size of 10 MB
# using at most one backup file. A2's layout is TTCC, using the
# ISO8061 date format with context printing enabled.
log4j.appender.A2=org.apache.log4j.RollingFileAppender
log4j.appender.A2.MaxFileSize=10MB
log4j.appender.A2.MaxBackupIndex=1
log4j.appender.A2.layout=org.apache.log4j.TTCCLayout
log4j.appender.A2.layout.ContextPrinting=enabled
log4j.appender.A2.layout.DateFormat=ISO8601
# Root logger set to DEBUG using the A2 appender defined above.
log4j.rootLogger=DEBUG, A2
# Logger definitions:
# The SECURITY logger inherits is level from root. However, it's output
# will go to A1 appender defined above. It's additivity is non-cumulative.
log4j.logger.SECURITY=INHERIT, A1
log4j.additivity.SECURITY=false
# Only warnings or above will be logged for the logger "SECURITY.access".
# Output will go to A1.
log4j.logger.SECURITY.access=WARN
# The logger "class.of.the.day" inherits its level from the
# logger hierarchy. Output will go to the appender's of the root
# logger, A2 in this case.
log4j.logger.class.of.the.day=INHERIT
Refer to the setOption method in each Appender and
Layout for class specific options.
Use the #
or !
characters at the
beginning of a line for comments.
@param configFileName The name of the configuration file where the
configuration information is stored.
*/
public
void doConfigure(String configFileName, LoggerRepository hierarchy) {
Properties props = new Properties();
try {
FileInputStream istream = new FileInputStream(configFileName);
props.load(istream);
istream.close();
}
catch (IOException e) {
LogLog.error("Could not read configuration file ["+configFileName+"].", e);
LogLog.error("Ignoring configuration file [" + configFileName+"].");
return;
}
// If we reach here, then the config file is alright.
doConfigure(props, hierarchy);
}
/**
*/
static
public
void configure(String configFilename) {
new PropertyConfigurator().doConfigure(configFilename,
LogManager.getLoggerRepository());
}
/**
Read configuration options from url configURL
.
@since 0.8.2
*/
public
static
void configure(java.net.URL configURL) {
new PropertyConfigurator().doConfigure(configURL,
LogManager.getLoggerRepository());
}
/**
Read configuration options from properties
.
See {@link #doConfigure(String, LoggerRepository)} for the expected format.
*/
static
public
void configure(Properties properties) {
new PropertyConfigurator().doConfigure(properties,
LogManager.getLoggerRepository());
}
/**
Like {@link #configureAndWatch(String, long)} except that the
default delay as defined by {@link FileWatchdog#DEFAULT_DELAY} is
used.
@param configFilename A file in key=value format.
*/
static
public
void configureAndWatch(String configFilename) {
configureAndWatch(configFilename, FileWatchdog.DEFAULT_DELAY);
}
/**
Read the configuration file configFilename
if it
exists. Moreover, a thread will be created that will periodically
check if configFilename
has been created or
modified. The period is determined by the delay
argument. If a change or file creation is detected, then
configFilename
is read to configure log4j.
@param configFilename A file in key=value format.
@param delay The delay in milliseconds to wait between each check.
*/
static
public
void configureAndWatch(String configFilename, long delay) {
PropertyWatchdog pdog = new PropertyWatchdog(configFilename);
pdog.setDelay(delay);
pdog.start();
}
/**
Read configuration options from properties
.
See {@link #doConfigure(String, LoggerRepository)} for the expected format.
*/
public
void doConfigure(Properties properties, LoggerRepository hierarchy) {
String value = properties.getProperty(LogLog.DEBUG_KEY);
if(value == null) {
value = properties.getProperty(LogLog.CONFIG_DEBUG_KEY);
if(value != null)
LogLog.warn("[log4j.configDebug] is deprecated. Use [log4j.debug] instead.");
}
if(value != null) {
LogLog.setInternalDebugging(OptionConverter.toBoolean(value, true));
}
String thresholdStr = OptionConverter.findAndSubst(THRESHOLD_PREFIX,
properties);
if(thresholdStr != null) {
hierarchy.setThreshold(OptionConverter.toLevel(thresholdStr,
(Level) Level.ALL));
LogLog.debug("Hierarchy threshold set to ["+hierarchy.getThreshold()+"].");
}
configureRootCategory(properties, hierarchy);
configureLoggerFactory(properties);
parseCatsAndRenderers(properties, hierarchy);
LogLog.debug("Finished configuring.");
// We don't want to hold references to appenders preventing their
// garbage collection.
registry.clear();
}
/**
Read configuration options from url configURL
.
*/
public
void doConfigure(java.net.URL configURL, LoggerRepository hierarchy) {
Properties props = new Properties();
LogLog.debug("Reading configuration from URL " + configURL);
try {
props.load(configURL.openStream());
}
catch (java.io.IOException e) {
LogLog.error("Could not read configuration file from URL [" + configURL
+ "].", e);
LogLog.error("Ignoring configuration file [" + configURL +"].");
return;
}
doConfigure(props, hierarchy);
}
// --------------------------------------------------------------------------
// Internal stuff
// --------------------------------------------------------------------------
/**
Check the provided Properties
object for a
{@link org.apache.log4j.spi.LoggerFactory LoggerFactory}
entry specified by {@link #LOGGER_FACTORY_KEY}. If such an entry
exists, an attempt is made to create an instance using the default
constructor. This instance is used for subsequent Category creations
within this configurator.
@see #parseCatsAndRenderers
*/
protected void configureLoggerFactory(Properties props) {
String factoryClassName = OptionConverter.findAndSubst(LOGGER_FACTORY_KEY,
props);
if(factoryClassName != null) {
LogLog.debug("Setting category factory to ["+factoryClassName+"].");
loggerFactory = (LoggerFactory)
OptionConverter.instantiateByClassName(factoryClassName,
LoggerFactory.class,
loggerFactory);
PropertySetter.setProperties(loggerFactory, props, FACTORY_PREFIX + ".");
}
}
/*
void configureOptionHandler(OptionHandler oh, String prefix,
Properties props) {
String[] options = oh.getOptionStrings();
if(options == null)
return;
String value;
for(int i = 0; i < options.length; i++) {
value = OptionConverter.findAndSubst(prefix + options[i], props);
LogLog.debug(
"Option " + options[i] + "=[" + (value == null? "N/A" : value)+"].");
// Some option handlers assume that null value are not passed to them.
// So don't remove this check
if(value != null) {
oh.setOption(options[i], value);
}
}
oh.activateOptions();
}
*/
void configureRootCategory(Properties props, LoggerRepository hierarchy) {
String effectiveFrefix = ROOT_LOGGER_PREFIX;
String value = OptionConverter.findAndSubst(ROOT_LOGGER_PREFIX, props);
if(value == null) {
value = OptionConverter.findAndSubst(ROOT_CATEGORY_PREFIX, props);
effectiveFrefix = ROOT_CATEGORY_PREFIX;
}
if(value == null)
LogLog.debug("Could not find root logger information. Is this OK?");
else {
Logger root = hierarchy.getRootLogger();
synchronized(root) {
parseCategory(props, root, effectiveFrefix, INTERNAL_ROOT_NAME, value);
}
}
}
/**
Parse non-root elements, such non-root categories and renderers.
*/
protected
void parseCatsAndRenderers(Properties props, LoggerRepository hierarchy) {
Enumeration enum = props.propertyNames();
while(enum.hasMoreElements()) {
String key = (String) enum.nextElement();
if(key.startsWith(CATEGORY_PREFIX) || key.startsWith(LOGGER_PREFIX)) {
String loggerName = null;
if(key.startsWith(CATEGORY_PREFIX)) {
loggerName = key.substring(CATEGORY_PREFIX.length());
} else if(key.startsWith(LOGGER_PREFIX)) {
loggerName = key.substring(LOGGER_PREFIX.length());
}
String value = OptionConverter.findAndSubst(key, props);
Logger logger = hierarchy.getLogger(loggerName, loggerFactory);
synchronized(logger) {
parseCategory(props, logger, key, loggerName, value);
parseAdditivityForLogger(props, logger, loggerName);
}
} else if(key.startsWith(RENDERER_PREFIX)) {
String renderedClass = key.substring(RENDERER_PREFIX.length());
String renderingClass = OptionConverter.findAndSubst(key, props);
if(hierarchy instanceof RendererSupport) {
RendererMap.addRenderer((RendererSupport) hierarchy, renderedClass,
renderingClass);
}
}
}
}
/**
Parse the additivity option for a non-root category.
*/
void parseAdditivityForLogger(Properties props, Logger cat,
String loggerName) {
String value = OptionConverter.findAndSubst(ADDITIVITY_PREFIX + loggerName,
props);
LogLog.debug("Handling "+ADDITIVITY_PREFIX + loggerName+"=["+value+"]");
// touch additivity only if necessary
if((value != null) && (!value.equals(""))) {
boolean additivity = OptionConverter.toBoolean(value, true);
LogLog.debug("Setting additivity for \""+loggerName+"\" to "+
additivity);
cat.setAdditivity(additivity);
}
}
/**
This method must work for the root category as well.
*/
void parseCategory(Properties props, Logger logger, String optionKey,
String loggerName, String value) {
LogLog.debug("Parsing for [" +loggerName +"] with value=[" + value+"].");
// We must skip over ',' but not white space
StringTokenizer st = new StringTokenizer(value, ",");
// If value is not in the form ", appender.." or "", then we should set
// the level of the loggeregory.
if(!(value.startsWith(",") || value.equals(""))) {
// just to be on the safe side...
if(!st.hasMoreTokens())
return;
String levelStr = st.nextToken();
LogLog.debug("Level token is [" + levelStr + "].");
// If the level value is inherited, set category level value to
// null. We also check that the user has not specified inherited for the
// root category.
if(INHERITED.equalsIgnoreCase(levelStr) ||
NULL.equalsIgnoreCase(levelStr)) {
if(loggerName.equals(INTERNAL_ROOT_NAME)) {
LogLog.warn("The root logger cannot be set to null.");
} else {
logger.setLevel(null);
}
} else {
logger.setLevel(OptionConverter.toLevel(levelStr, (Level) Level.DEBUG));
}
LogLog.debug("Category " + loggerName + " set to " + logger.getLevel());
}
// Begin by removing all existing appenders.
logger.removeAllAppenders();
Appender appender;
String appenderName;
while(st.hasMoreTokens()) {
appenderName = st.nextToken().trim();
if(appenderName == null || appenderName.equals(","))
continue;
LogLog.debug("Parsing appender named \"" + appenderName +"\".");
appender = parseAppender(props, appenderName);
if(appender != null) {
logger.addAppender(appender);
}
}
}
Appender parseAppender(Properties props, String appenderName) {
Appender appender = registryGet(appenderName);
if((appender != null)) {
LogLog.debug("Appender \"" + appenderName + "\" was already parsed.");
return appender;
}
// Appender was not previously initialized.
String prefix = APPENDER_PREFIX + appenderName;
String layoutPrefix = prefix + ".layout";
appender = (Appender) OptionConverter.instantiateByKey(props, prefix,
org.apache.log4j.Appender.class,
null);
if(appender == null) {
LogLog.error(
"Could not instantiate appender named \"" + appenderName+"\".");
return null;
}
appender.setName(appenderName);
if(appender instanceof OptionHandler) {
if(appender.requiresLayout()) {
Layout layout = (Layout) OptionConverter.instantiateByKey(props,
layoutPrefix,
Layout.class,
null);
if(layout != null) {
appender.setLayout(layout);
LogLog.debug("Parsing layout options for \"" + appenderName +"\".");
//configureOptionHandler(layout, layoutPrefix + ".", props);
PropertySetter.setProperties(layout, props, layoutPrefix + ".");
LogLog.debug("End of parsing for \"" + appenderName +"\".");
}
}
//configureOptionHandler((OptionHandler) appender, prefix + ".", props);
PropertySetter.setProperties(appender, props, prefix + ".");
LogLog.debug("Parsed \"" + appenderName +"\" options.");
}
registryPut(appender);
return appender;
}
void registryPut(Appender appender) {
registry.put(appender.getName(), appender);
}
Appender registryGet(String name) {
return (Appender) registry.get(name);
}
}
class PropertyWatchdog extends FileWatchdog {
PropertyWatchdog(String filename) {
super(filename);
}
/**
Call {@link PropertyConfigurator#configure(String)} with the
filename
to reconfigure log4j. */
public
void doOnChange() {
new PropertyConfigurator().doConfigure(filename,
LogManager.getLoggerRepository());
}
}