* Logger objects may be obtained by calls on one of the getLogger * factory methods. These will either create a new Logger or * return a suitable existing Logger. It is important to note that * the Logger returned by one of the {@code getLogger} factory methods * may be garbage collected at any time if a strong reference to the * Logger is not kept. *
* Logging messages will be forwarded to registered Handler * objects, which can forward the messages to a variety of * destinations, including consoles, files, OS logs, etc. *
* Each Logger keeps track of a "parent" Logger, which is its * nearest existing ancestor in the Logger namespace. *
* Each Logger has a "Level" associated with it. This reflects * a minimum Level that this logger cares about. If a Logger's * level is set to null, then its effective level is inherited * from its parent, which may in turn obtain it recursively from its * parent, and so on up the tree. *
* The log level can be configured based on the properties from the * logging configuration file, as described in the description * of the LogManager class. However it may also be dynamically changed * by calls on the Logger.setLevel method. If a logger's level is * changed the change may also affect child loggers, since any child * logger that has null as its level will inherit its * effective level from its parent. *
* On each logging call the Logger initially performs a cheap * check of the request level (e.g., SEVERE or FINE) against the * effective log level of the logger. If the request level is * lower than the log level, the logging call returns immediately. *
* After passing this initial (cheap) test, the Logger will allocate * a LogRecord to describe the logging message. It will then call a * Filter (if present) to do a more detailed check on whether the * record should be published. If that passes it will then publish * the LogRecord to its output Handlers. By default, loggers also * publish to their parent's Handlers, recursively up the tree. *
* Each Logger may have a ResourceBundle name associated with it. * The named bundle will be used for localizing logging messages. * If a Logger does not have its own ResourceBundle name, then * it will inherit the ResourceBundle name from its parent, * recursively up the tree. *
* Most of the logger output methods take a "msg" argument. This * msg argument may be either a raw value or a localization key. * During formatting, if the logger has (or inherits) a localization * ResourceBundle and if the ResourceBundle has a mapping for the msg * string, then the msg string is replaced by the localized value. * Otherwise the original msg string is used. Typically, formatters use * java.text.MessageFormat style formatting to format parameters, so * for example a format string "{0} {1}" would format two parameters * as strings. *
* When mapping ResourceBundle names to ResourceBundles, the Logger * will first try to use the Thread's ContextClassLoader. If that * is null it will try the SystemClassLoader instead. As a temporary * transition feature in the initial implementation, if the Logger is * unable to locate a ResourceBundle from the ContextClassLoader or * SystemClassLoader the Logger will also search up the class stack * and use successive calling ClassLoaders to try to locate a ResourceBundle. * (This call stack search is to allow containers to transition to * using ContextClassLoaders and is likely to be removed in future * versions.) *
* Formatting (including localization) is the responsibility of * the output Handler, which will typically call a Formatter. *
* Note that formatting need not occur synchronously. It may be delayed * until a LogRecord is actually written to an external sink. *
* The logging methods are grouped in five main categories: *
* There are a set of "log" methods that take a log level, a message * string, and optionally some parameters to the message string. *
* There are a set of "logp" methods (for "log precise") that are * like the "log" methods, but also take an explicit source class name * and method name. *
* There are a set of "logrb" method (for "log with resource bundle") * that are like the "logp" method, but also take an explicit resource * bundle name for use in localizing the log message. *
* There are convenience methods for tracing method entries (the * "entering" methods), method returns (the "exiting" methods) and * throwing exceptions (the "throwing" methods). *
* Finally, there are a set of convenience methods for use in the * very simplest cases, when a developer simply wants to log a * simple string at a given log level. These methods are named * after the standard Level names ("severe", "warning", "info", etc.) * and take a single argument, a message string. *
* For the methods that do not take an explicit source name and * method name, the Logging framework will make a "best effort" * to determine which class and method called into the logging method. * However, it is important to realize that this automatically inferred * information may only be approximate (or may even be quite wrong!). * Virtual machines are allowed to do extensive optimizations when * JITing and may entirely remove stack frames, making it impossible * to reliably locate the calling class and method. *
* All methods on Logger are multi-thread safe. *
* Subclassing Information: Note that a LogManager class may
* provide its own implementation of named Loggers for any point in
* the namespace. Therefore, any subclasses of Logger (unless they
* are implemented in conjunction with a new LogManager class) should
* take care to obtain a Logger instance from the LogManager class and
* should delegate operations such as "isLoggable" and "log(LogRecord)"
* to that instance. Note that in order to intercept all logging
* output, subclasses need only override the log(LogRecord) method.
* All the other logging methods are implemented as calls on this
* log(LogRecord) method.
*
* @since 1.4
*/
public class Logger {
private static final Handler emptyHandlers[] = new Handler[0];
private static final int offValue = Level.OFF.intValue();
private LogManager manager;
private String name;
private final CopyOnWriteArrayList
* @deprecated Initialization of this field is prone to deadlocks.
* The field must be initialized by the Logger class initialization
* which may cause deadlocks with the LogManager class initialization.
* In such cases two class initialization wait for each other to complete.
* The preferred way to get the global logger object is via the call
*
* The logger will be initially configured with a null Level
* and with useParentHandlers set to true.
*
* @param name A name for the logger. This should
* be a dot-separated name and should normally
* be based on the package name or class name
* of the subsystem, such as java.net
* or javax.swing. It may be null for anonymous Loggers.
* @param resourceBundleName name of ResourceBundle to be used for localizing
* messages for this logger. May be null if none
* of the messages require localization.
* @throws MissingResourceException if the resourceBundleName is non-null and
* no corresponding resource can be found.
*/
protected Logger(String name, String resourceBundleName) {
this.manager = LogManager.getLogManager();
if (resourceBundleName != null) {
// Note: we may get a MissingResourceException here.
setupResourceInfo(resourceBundleName);
}
this.name = name;
levelValue = Level.INFO.intValue();
}
// This constructor is used only to create the global Logger.
// It is needed to break a cyclic dependence between the LogManager
// and Logger static initializers causing deadlocks.
private Logger(String name) {
// The manager field is not initialized here.
this.name = name;
levelValue = Level.INFO.intValue();
}
// It is called from the LogManager.
* If a new logger is created its log level will be configured
* based on the LogManager configuration and it will configured
* to also send logging output to its parent's Handlers. It will
* be registered in the LogManager global namespace.
*
* Note: The LogManager may only retain a weak reference to the newly
* created Logger. It is important to understand that a previously
* created Logger with the given name may be garbage collected at any
* time if there is no strong reference to the Logger. In particular,
* this means that two back-to-back calls like
* {@code getLogger("MyLogger").log(...)} may use different Logger
* objects named "MyLogger" if there is no strong reference to the
* Logger named "MyLogger" elsewhere in the program.
*
* @param name A name for the logger. This should
* be a dot-separated name and should normally
* be based on the package name or class name
* of the subsystem, such as java.net
* or javax.swing
* @return a suitable Logger
* @throws NullPointerException if the name is null.
*/
public static synchronized Logger getLogger(String name) {
LogManager manager = LogManager.getLogManager();
return manager.demandLogger(name);
}
/**
* Find or create a logger for a named subsystem. If a logger has
* already been created with the given name it is returned. Otherwise
* a new logger is created.
*
* If a new logger is created its log level will be configured
* based on the LogManager and it will configured to also send logging
* output to its parent's Handlers. It will be registered in
* the LogManager global namespace.
*
* Note: The LogManager may only retain a weak reference to the newly
* created Logger. It is important to understand that a previously
* created Logger with the given name may be garbage collected at any
* time if there is no strong reference to the Logger. In particular,
* this means that two back-to-back calls like
* {@code getLogger("MyLogger", ...).log(...)} may use different Logger
* objects named "MyLogger" if there is no strong reference to the
* Logger named "MyLogger" elsewhere in the program.
*
* If the named Logger already exists and does not yet have a
* localization resource bundle then the given resource bundle
* name is used. If the named Logger already exists and has
* a different resource bundle name then an IllegalArgumentException
* is thrown.
*
* @param name A name for the logger. This should
* be a dot-separated name and should normally
* be based on the package name or class name
* of the subsystem, such as java.net
* or javax.swing
* @param resourceBundleName name of ResourceBundle to be used for localizing
* messages for this logger. May be
* This factory method is primarily intended for use from applets.
* Because the resulting Logger is anonymous it can be kept private
* by the creating class. This removes the need for normal security
* checks, which in turn allows untrusted applet code to update
* the control state of the Logger. For example an applet can do
* a setLevel or an addHandler on an anonymous Logger.
*
* Even although the new logger is anonymous, it is configured
* to have the root logger ("") as its parent. This means that
* by default it inherits its effective level and handlers
* from the root logger.
*
*
* @return a newly created private Logger
*/
public static Logger getAnonymousLogger() {
return getAnonymousLogger(null);
}
/**
* Create an anonymous Logger. The newly created Logger is not
* registered in the LogManager namespace. There will be no
* access checks on updates to the logger.
*
* This factory method is primarily intended for use from applets.
* Because the resulting Logger is anonymous it can be kept private
* by the creating class. This removes the need for normal security
* checks, which in turn allows untrusted applet code to update
* the control state of the Logger. For example an applet can do
* a setLevel or an addHandler on an anonymous Logger.
*
* Even although the new logger is anonymous, it is configured
* to have the root logger ("") as its parent. This means that
* by default it inherits its effective level and handlers
* from the root logger.
*
* @param resourceBundleName name of ResourceBundle to be used for localizing
* messages for this logger.
* May be null if none of the messages require localization.
* @return a newly created private Logger
* @throws MissingResourceException if the resourceBundleName is non-null and
* no corresponding resource can be found.
*/
public static synchronized Logger getAnonymousLogger(String resourceBundleName) {
LogManager manager = LogManager.getLogManager();
// cleanup some Loggers that have been GC'ed
manager.drainLoggerRefQueueBounded();
Logger result = new Logger(null, resourceBundleName);
result.anonymous = true;
Logger root = manager.getLogger("");
result.doSetParent(root);
return result;
}
/**
* Retrieve the localization resource bundle for this
* logger for the current default locale. Note that if
* the result is null, then the Logger will use a resource
* bundle inherited from its parent.
*
* @return localization bundle (may be null)
*/
public ResourceBundle getResourceBundle() {
return findResourceBundle(getResourceBundleName());
}
/**
* Retrieve the localization resource bundle name for this
* logger. Note that if the result is null, then the Logger
* will use a resource bundle name inherited from its parent.
*
* @return localization bundle name (may be null)
*/
public String getResourceBundleName() {
return resourceBundleName;
}
/**
* Set a filter to control output on this Logger.
*
* After passing the initial "level" check, the Logger will
* call this Filter to check if a log record should really
* be published.
*
* @param newFilter a filter object (may be null)
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void setFilter(Filter newFilter) throws SecurityException {
checkAccess();
filter = newFilter;
}
/**
* Get the current filter for this Logger.
*
* @return a filter object (may be null)
*/
public Filter getFilter() {
return filter;
}
/**
* Log a LogRecord.
*
* All the other logging methods in this class call through
* this method to actually perform any logging. Subclasses can
* override this single method to capture all log activity.
*
* @param record the LogRecord to be published
*/
public void log(LogRecord record) {
if (record.getLevel().intValue() < levelValue || levelValue == offValue) {
return;
}
Filter theFilter = filter;
if (theFilter != null && !theFilter.isLoggable(record)) {
return;
}
// Post the LogRecord to all our Handlers, and then to
// our parents' handlers, all the way up the tree.
Logger logger = this;
while (logger != null) {
for (Handler handler : logger.getHandlers()) {
handler.publish(record);
}
if (!logger.getUseParentHandlers()) {
break;
}
logger = logger.getParent();
}
}
// private support method for logging.
// We fill in the logger name, resource bundle name, and
// resource bundle and then call "void log(LogRecord)".
private void doLog(LogRecord lr) {
lr.setLoggerName(name);
String ebname = getEffectiveResourceBundleName();
if (ebname != null) {
lr.setResourceBundleName(ebname);
lr.setResourceBundle(findResourceBundle(ebname));
}
log(lr);
}
//================================================================
// Start of convenience methods WITHOUT className and methodName
//================================================================
/**
* Log a message, with no arguments.
*
* If the logger is currently enabled for the given message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param msg The string message (or a key in the message catalog)
*/
public void log(Level level, String msg) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
doLog(lr);
}
/**
* Log a message, with one object parameter.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param msg The string message (or a key in the message catalog)
* @param param1 parameter to the message
*/
public void log(Level level, String msg, Object param1) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
Object params[] = { param1 };
lr.setParameters(params);
doLog(lr);
}
/**
* Log a message, with an array of object arguments.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param msg The string message (or a key in the message catalog)
* @param params array of parameters to the message
*/
public void log(Level level, String msg, Object params[]) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setParameters(params);
doLog(lr);
}
/**
* Log a message, with associated Throwable information.
*
* If the logger is currently enabled for the given message
* level then the given arguments are stored in a LogRecord
* which is forwarded to all registered output handlers.
*
* Note that the thrown argument is stored in the LogRecord thrown
* property, rather than the LogRecord parameters property. Thus is it
* processed specially by output Formatters and is not treated
* as a formatting parameter to the LogRecord message property.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param msg The string message (or a key in the message catalog)
* @param thrown Throwable associated with log message.
*/
public void log(Level level, String msg, Throwable thrown) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setThrown(thrown);
doLog(lr);
}
//================================================================
// Start of convenience methods WITH className and methodName
//================================================================
/**
* Log a message, specifying source class and method,
* with no arguments.
*
* If the logger is currently enabled for the given message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param msg The string message (or a key in the message catalog)
*/
public void logp(Level level, String sourceClass, String sourceMethod, String msg) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
doLog(lr);
}
/**
* Log a message, specifying source class and method,
* with a single object parameter to the log message.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param msg The string message (or a key in the message catalog)
* @param param1 Parameter to the log message.
*/
public void logp(Level level, String sourceClass, String sourceMethod,
String msg, Object param1) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
Object params[] = { param1 };
lr.setParameters(params);
doLog(lr);
}
/**
* Log a message, specifying source class and method,
* with an array of object arguments.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param msg The string message (or a key in the message catalog)
* @param params Array of parameters to the message
*/
public void logp(Level level, String sourceClass, String sourceMethod,
String msg, Object params[]) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
lr.setParameters(params);
doLog(lr);
}
/**
* Log a message, specifying source class and method,
* with associated Throwable information.
*
* If the logger is currently enabled for the given message
* level then the given arguments are stored in a LogRecord
* which is forwarded to all registered output handlers.
*
* Note that the thrown argument is stored in the LogRecord thrown
* property, rather than the LogRecord parameters property. Thus is it
* processed specially by output Formatters and is not treated
* as a formatting parameter to the LogRecord message property.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param msg The string message (or a key in the message catalog)
* @param thrown Throwable associated with log message.
*/
public void logp(Level level, String sourceClass, String sourceMethod,
String msg, Throwable thrown) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
lr.setThrown(thrown);
doLog(lr);
}
//=========================================================================
// Start of convenience methods WITH className, methodName and bundle name.
//=========================================================================
// Private support method for logging for "logrb" methods.
// We fill in the logger name, resource bundle name, and
// resource bundle and then call "void log(LogRecord)".
private void doLog(LogRecord lr, String rbname) {
lr.setLoggerName(name);
if (rbname != null) {
lr.setResourceBundleName(rbname);
lr.setResourceBundle(findResourceBundle(rbname));
}
log(lr);
}
/**
* Log a message, specifying source class, method, and resource bundle name
* with no arguments.
*
* If the logger is currently enabled for the given message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* The msg string is localized using the named resource bundle. If the
* resource bundle name is null, or an empty String or invalid
* then the msg string is not localized.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param bundleName name of resource bundle to localize msg,
* can be null
* @param msg The string message (or a key in the message catalog)
*/
public void logrb(Level level, String sourceClass, String sourceMethod,
String bundleName, String msg) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
doLog(lr, bundleName);
}
/**
* Log a message, specifying source class, method, and resource bundle name,
* with a single object parameter to the log message.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* The msg string is localized using the named resource bundle. If the
* resource bundle name is null, or an empty String or invalid
* then the msg string is not localized.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param bundleName name of resource bundle to localize msg,
* can be null
* @param msg The string message (or a key in the message catalog)
* @param param1 Parameter to the log message.
*/
public void logrb(Level level, String sourceClass, String sourceMethod,
String bundleName, String msg, Object param1) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
Object params[] = { param1 };
lr.setParameters(params);
doLog(lr, bundleName);
}
/**
* Log a message, specifying source class, method, and resource bundle name,
* with an array of object arguments.
*
* If the logger is currently enabled for the given message
* level then a corresponding LogRecord is created and forwarded
* to all the registered output Handler objects.
*
* The msg string is localized using the named resource bundle. If the
* resource bundle name is null, or an empty String or invalid
* then the msg string is not localized.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param bundleName name of resource bundle to localize msg,
* can be null.
* @param msg The string message (or a key in the message catalog)
* @param params Array of parameters to the message
*/
public void logrb(Level level, String sourceClass, String sourceMethod,
String bundleName, String msg, Object params[]) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
lr.setParameters(params);
doLog(lr, bundleName);
}
/**
* Log a message, specifying source class, method, and resource bundle name,
* with associated Throwable information.
*
* If the logger is currently enabled for the given message
* level then the given arguments are stored in a LogRecord
* which is forwarded to all registered output handlers.
*
* The msg string is localized using the named resource bundle. If the
* resource bundle name is null, or an empty String or invalid
* then the msg string is not localized.
*
* Note that the thrown argument is stored in the LogRecord thrown
* property, rather than the LogRecord parameters property. Thus is it
* processed specially by output Formatters and is not treated
* as a formatting parameter to the LogRecord message property.
*
* @param level One of the message level identifiers, e.g., SEVERE
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that issued the logging request
* @param bundleName name of resource bundle to localize msg,
* can be null
* @param msg The string message (or a key in the message catalog)
* @param thrown Throwable associated with log message.
*/
public void logrb(Level level, String sourceClass, String sourceMethod,
String bundleName, String msg, Throwable thrown) {
if (level.intValue() < levelValue || levelValue == offValue) {
return;
}
LogRecord lr = new LogRecord(level, msg);
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
lr.setThrown(thrown);
doLog(lr, bundleName);
}
//======================================================================
// Start of convenience methods for logging method entries and returns.
//======================================================================
/**
* Log a method entry.
*
* This is a convenience method that can be used to log entry
* to a method. A LogRecord with message "ENTRY", log level
* FINER, and the given sourceMethod and sourceClass is logged.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that is being entered
*/
public void entering(String sourceClass, String sourceMethod) {
if (Level.FINER.intValue() < levelValue) {
return;
}
logp(Level.FINER, sourceClass, sourceMethod, "ENTRY");
}
/**
* Log a method entry, with one parameter.
*
* This is a convenience method that can be used to log entry
* to a method. A LogRecord with message "ENTRY {0}", log level
* FINER, and the given sourceMethod, sourceClass, and parameter
* is logged.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that is being entered
* @param param1 parameter to the method being entered
*/
public void entering(String sourceClass, String sourceMethod, Object param1) {
if (Level.FINER.intValue() < levelValue) {
return;
}
Object params[] = { param1 };
logp(Level.FINER, sourceClass, sourceMethod, "ENTRY {0}", params);
}
/**
* Log a method entry, with an array of parameters.
*
* This is a convenience method that can be used to log entry
* to a method. A LogRecord with message "ENTRY" (followed by a
* format {N} indicator for each entry in the parameter array),
* log level FINER, and the given sourceMethod, sourceClass, and
* parameters is logged.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of method that is being entered
* @param params array of parameters to the method being entered
*/
public void entering(String sourceClass, String sourceMethod, Object params[]) {
if (Level.FINER.intValue() < levelValue) {
return;
}
String msg = "ENTRY";
if (params == null ) {
logp(Level.FINER, sourceClass, sourceMethod, msg);
return;
}
for (int i = 0; i < params.length; i++) {
msg = msg + " {" + i + "}";
}
logp(Level.FINER, sourceClass, sourceMethod, msg, params);
}
/**
* Log a method return.
*
* This is a convenience method that can be used to log returning
* from a method. A LogRecord with message "RETURN", log level
* FINER, and the given sourceMethod and sourceClass is logged.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of the method
*/
public void exiting(String sourceClass, String sourceMethod) {
if (Level.FINER.intValue() < levelValue) {
return;
}
logp(Level.FINER, sourceClass, sourceMethod, "RETURN");
}
/**
* Log a method return, with result object.
*
* This is a convenience method that can be used to log returning
* from a method. A LogRecord with message "RETURN {0}", log level
* FINER, and the gives sourceMethod, sourceClass, and result
* object is logged.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of the method
* @param result Object that is being returned
*/
public void exiting(String sourceClass, String sourceMethod, Object result) {
if (Level.FINER.intValue() < levelValue) {
return;
}
Object params[] = { result };
logp(Level.FINER, sourceClass, sourceMethod, "RETURN {0}", result);
}
/**
* Log throwing an exception.
*
* This is a convenience method to log that a method is
* terminating by throwing an exception. The logging is done
* using the FINER level.
*
* If the logger is currently enabled for the given message
* level then the given arguments are stored in a LogRecord
* which is forwarded to all registered output handlers. The
* LogRecord's message is set to "THROW".
*
* Note that the thrown argument is stored in the LogRecord thrown
* property, rather than the LogRecord parameters property. Thus is it
* processed specially by output Formatters and is not treated
* as a formatting parameter to the LogRecord message property.
*
* @param sourceClass name of class that issued the logging request
* @param sourceMethod name of the method.
* @param thrown The Throwable that is being thrown.
*/
public void throwing(String sourceClass, String sourceMethod, Throwable thrown) {
if (Level.FINER.intValue() < levelValue || levelValue == offValue ) {
return;
}
LogRecord lr = new LogRecord(Level.FINER, "THROW");
lr.setSourceClassName(sourceClass);
lr.setSourceMethodName(sourceMethod);
lr.setThrown(thrown);
doLog(lr);
}
//=======================================================================
// Start of simple convenience methods using level names as method names
//=======================================================================
/**
* Log a SEVERE message.
*
* If the logger is currently enabled for the SEVERE message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void severe(String msg) {
if (Level.SEVERE.intValue() < levelValue) {
return;
}
log(Level.SEVERE, msg);
}
/**
* Log a WARNING message.
*
* If the logger is currently enabled for the WARNING message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void warning(String msg) {
if (Level.WARNING.intValue() < levelValue) {
return;
}
log(Level.WARNING, msg);
}
/**
* Log an INFO message.
*
* If the logger is currently enabled for the INFO message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void info(String msg) {
if (Level.INFO.intValue() < levelValue) {
return;
}
log(Level.INFO, msg);
}
/**
* Log a CONFIG message.
*
* If the logger is currently enabled for the CONFIG message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void config(String msg) {
if (Level.CONFIG.intValue() < levelValue) {
return;
}
log(Level.CONFIG, msg);
}
/**
* Log a FINE message.
*
* If the logger is currently enabled for the FINE message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void fine(String msg) {
if (Level.FINE.intValue() < levelValue) {
return;
}
log(Level.FINE, msg);
}
/**
* Log a FINER message.
*
* If the logger is currently enabled for the FINER message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void finer(String msg) {
if (Level.FINER.intValue() < levelValue) {
return;
}
log(Level.FINER, msg);
}
/**
* Log a FINEST message.
*
* If the logger is currently enabled for the FINEST message
* level then the given message is forwarded to all the
* registered output Handler objects.
*
* @param msg The string message (or a key in the message catalog)
*/
public void finest(String msg) {
if (Level.FINEST.intValue() < levelValue) {
return;
}
log(Level.FINEST, msg);
}
//================================================================
// End of convenience methods
//================================================================
/**
* Set the log level specifying which message levels will be
* logged by this logger. Message levels lower than this
* value will be discarded. The level value Level.OFF
* can be used to turn off logging.
*
* If the new level is null, it means that this node should
* inherit its level from its nearest ancestor with a specific
* (non-null) level value.
*
* @param newLevel the new value for the log level (may be null)
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void setLevel(Level newLevel) throws SecurityException {
checkAccess();
synchronized (treeLock) {
levelObject = newLevel;
updateEffectiveLevel();
}
}
/**
* Get the log Level that has been specified for this Logger.
* The result may be null, which means that this logger's
* effective level will be inherited from its parent.
*
* @return this Logger's level
*/
public Level getLevel() {
return levelObject;
}
/**
* Check if a message of the given level would actually be logged
* by this logger. This check is based on the Loggers effective level,
* which may be inherited from its parent.
*
* @param level a message logging level
* @return true if the given message level is currently being logged.
*/
public boolean isLoggable(Level level) {
if (level.intValue() < levelValue || levelValue == offValue) {
return false;
}
return true;
}
/**
* Get the name for this logger.
* @return logger name. Will be null for anonymous Loggers.
*/
public String getName() {
return name;
}
/**
* Add a log Handler to receive logging messages.
*
* By default, Loggers also send their output to their parent logger.
* Typically the root Logger is configured with a set of Handlers
* that essentially act as default handlers for all loggers.
*
* @param handler a logging Handler
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void addHandler(Handler handler) throws SecurityException {
// Check for null handler
handler.getClass();
checkAccess();
handlers.add(handler);
}
/**
* Remove a log Handler.
*
* Returns silently if the given Handler is not found or is null
*
* @param handler a logging Handler
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void removeHandler(Handler handler) throws SecurityException {
checkAccess();
if (handler == null) {
return;
}
handlers.remove(handler);
}
/**
* Get the Handlers associated with this logger.
*
* @return an array of all registered Handlers
*/
public Handler[] getHandlers() {
return handlers.toArray(emptyHandlers);
}
/**
* Specify whether or not this logger should send its output
* to its parent Logger. This means that any LogRecords will
* also be written to the parent's Handlers, and potentially
* to its parent, recursively up the namespace.
*
* @param useParentHandlers true if output is to be sent to the
* logger's parent.
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void setUseParentHandlers(boolean useParentHandlers) {
checkAccess();
this.useParentHandlers = useParentHandlers;
}
/**
* Discover whether or not this logger is sending its output
* to its parent logger.
*
* @return true if output is to be sent to the logger's parent
*/
public boolean getUseParentHandlers() {
return useParentHandlers;
}
// Private utility method to map a resource bundle name to an
// actual resource bundle, using a simple one-entry cache.
// Returns null for a null name.
// May also return null if we can't find the resource bundle and
// there is no suitable previous cached value.
private synchronized ResourceBundle findResourceBundle(String name) {
// Return a null bundle for a null name.
if (name == null) {
return null;
}
Locale currentLocale = Locale.getDefault();
// Normally we should hit on our simple one entry cache.
if (catalog != null && currentLocale == catalogLocale
&& name == catalogName) {
return catalog;
}
// Use the thread's context ClassLoader. If there isn't one,
// use the SystemClassloader.
ClassLoader cl = Thread.currentThread().getContextClassLoader();
if (cl == null) {
cl = ClassLoader.getSystemClassLoader();
}
try {
catalog = ResourceBundle.getBundle(name, currentLocale, cl);
catalogName = name;
catalogLocale = currentLocale;
return catalog;
} catch (MissingResourceException ex) {
// Woops. We can't find the ResourceBundle in the default
// ClassLoader. Drop through.
}
// Fall back to searching up the call stack and trying each
// calling ClassLoader.
for (int ix = 0; ; ix++) {
Class clz = sun.reflect.Reflection.getCallerClass(ix);
if (clz == null) {
break;
}
ClassLoader cl2 = clz.getClassLoader();
if (cl2 == null) {
cl2 = ClassLoader.getSystemClassLoader();
}
if (cl == cl2) {
// We've already checked this classloader.
continue;
}
cl = cl2;
try {
catalog = ResourceBundle.getBundle(name, currentLocale, cl);
catalogName = name;
catalogLocale = currentLocale;
return catalog;
} catch (MissingResourceException ex) {
// Ok, this one didn't work either.
// Drop through, and try the next one.
}
}
if (name.equals(catalogName)) {
// Return the previous cached value for that name.
// This may be null.
return catalog;
}
// Sorry, we're out of luck.
return null;
}
// Private utility method to initialize our one entry
// resource bundle cache.
// Note: for consistency reasons, we are careful to check
// that a suitable ResourceBundle exists before setting the
// ResourceBundleName.
private synchronized void setupResourceInfo(String name) {
if (name == null) {
return;
}
ResourceBundle rb = findResourceBundle(name);
if (rb == null) {
// We've failed to find an expected ResourceBundle.
throw new MissingResourceException("Can't find " + name + " bundle", name, "");
}
resourceBundleName = name;
}
/**
* Return the parent for this Logger.
*
* This method returns the nearest extant parent in the namespace.
* Thus if a Logger is called "a.b.c.d", and a Logger called "a.b"
* has been created but no logger "a.b.c" exists, then a call of
* getParent on the Logger "a.b.c.d" will return the Logger "a.b".
*
* The result will be null if it is called on the root Logger
* in the namespace.
*
* @return nearest existing parent Logger
*/
public Logger getParent() {
// Note: this used to be synchronized on treeLock. However, this only
// provided memory semantics, as there was no guarantee that the caller
// would synchronize on treeLock (in fact, there is no way for external
// callers to so synchronize). Therefore, we have made parent volatile
// instead.
return parent;
}
/**
* Set the parent for this Logger. This method is used by
* the LogManager to update a Logger when the namespace changes.
*
* It should not be called from application code.
*
* @param parent the new parent logger
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void setParent(Logger parent) {
if (parent == null) {
throw new NullPointerException();
}
manager.checkAccess();
doSetParent(parent);
}
// Private method to do the work for parenting a child
// Logger onto a parent logger.
private void doSetParent(Logger newParent) {
// System.err.println("doSetParent \"" + getName() + "\" \""
// + newParent.getName() + "\"");
synchronized (treeLock) {
// Remove ourself from any previous parent.
LogManager.LoggerWeakRef ref = null;
if (parent != null) {
// assert parent.kids != null;
for (IteratorLogger.getGlobal().
* For compatibility with old JDK versions where the
* Logger.getGlobal() is not available use the call
* Logger.getLogger(Logger.GLOBAL_LOGGER_NAME)
* or Logger.getLogger("global").
*/
@Deprecated
public static final Logger global = new Logger(GLOBAL_LOGGER_NAME);
/**
* Protected method to construct a logger for a named subsystem.
* null if none of
* the messages require localization.
* @return a suitable Logger
* @throws MissingResourceException if the resourceBundleName is non-null and
* no corresponding resource can be found.
* @throws IllegalArgumentException if the Logger already exists and uses
* a different resource bundle name.
* @throws NullPointerException if the name is null.
*/
public static synchronized Logger getLogger(String name, String resourceBundleName) {
LogManager manager = LogManager.getLogManager();
Logger result = manager.demandLogger(name);
if (result.resourceBundleName == null) {
// Note: we may get a MissingResourceException here.
result.setupResourceInfo(resourceBundleName);
} else if (!result.resourceBundleName.equals(resourceBundleName)) {
throw new IllegalArgumentException(result.resourceBundleName +
" != " + resourceBundleName);
}
return result;
}
/**
* Create an anonymous Logger. The newly created Logger is not
* registered in the LogManager namespace. There will be no
* access checks on updates to the logger.
*