A Logger object is used to log messages for a specific system or application component. Loggers are normally named, using a hierarchical dot-separated namespace. Logger names can be arbitrary strings, but they should normally be based on the package name or class name of the logged component, such as java.net or javax.swing. In addition it is possible to create "anonymous" Loggers that are not stored in the Logger namespace.
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 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 associated with it. The ResourceBundle may be specified by name, using the getLogger(java.lang.String, java.lang.String) factory method, or by value - using the setResourceBundle method. This bundle will be used for localizing logging messages. If a Logger does not have its own ResourceBundle or resource bundle name, then it will inherit the ResourceBundle or resource bundle 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.
A set of methods alternatively take a "msgSupplier" instead of a "msg" argument. These methods take a Supplier<String> function which is invoked to construct the desired log message only when the message actually is to be logged based on the effective log level thus eliminating unnecessary message construction. For example, if the developer wants to log system health status for diagnosis, with the String-accepting version, the code would look like:
class DiagnosisMessages { static String systemHealthStatus() { // collect system health information ... } } ... logger.log(Level.FINER, DiagnosisMessages.systemHealthStatus()); With the above code, the health status is collected unnecessarily even when the log level FINER is disabled. With the Supplier-accepting version as below, the status will only be collected when the log level FINER is enabled.
logger.log(Level.FINER, DiagnosisMessages::systemHealthStatus);
When looking for a ResourceBundle, the logger will first look at whether a bundle was specified using setResourceBundle, and then only whether a resource bundle name was specified through the getLogger factory method. If no ResourceBundle or no resource bundle name is found, then it will use the nearest ResourceBundle or resource bundle name inherited from its parent tree. When a ResourceBundle was inherited or specified through the setResourceBundle method, then that ResourceBundle will be used. Otherwise if the logger only has or inherited a resource bundle name, then that resource bundle name will be mapped to a ResourceBundle object, using the default Locale at the time of logging. When mapping resource bundle names to ResourceBundle objects, the logger will first try to use the Thread's context class loader to map the given resource bundle name to a ResourceBundle. If the thread context class loader is null, it will try the system class loader instead. If the ResourceBundle is still not found, it will use the class loader of the first caller of the getLogger factory method.
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 object 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.
A Logger object is used to log messages for a specific system or application component. Loggers are normally named, using a hierarchical dot-separated namespace. Logger names can be arbitrary strings, but they should normally be based on the package name or class name of the logged component, such as java.net or javax.swing. In addition it is possible to create "anonymous" Loggers that are not stored in the Logger namespace. 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 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 associated with it. The ResourceBundle may be specified by name, using the getLogger(java.lang.String, java.lang.String) factory method, or by value - using the setResourceBundle method. This bundle will be used for localizing logging messages. If a Logger does not have its own ResourceBundle or resource bundle name, then it will inherit the ResourceBundle or resource bundle 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. A set of methods alternatively take a "msgSupplier" instead of a "msg" argument. These methods take a Supplier<String> function which is invoked to construct the desired log message only when the message actually is to be logged based on the effective log level thus eliminating unnecessary message construction. For example, if the developer wants to log system health status for diagnosis, with the String-accepting version, the code would look like: class DiagnosisMessages { static String systemHealthStatus() { // collect system health information ... } } ... logger.log(Level.FINER, DiagnosisMessages.systemHealthStatus()); With the above code, the health status is collected unnecessarily even when the log level FINER is disabled. With the Supplier-accepting version as below, the status will only be collected when the log level FINER is enabled. logger.log(Level.FINER, DiagnosisMessages::systemHealthStatus); When looking for a ResourceBundle, the logger will first look at whether a bundle was specified using setResourceBundle, and then only whether a resource bundle name was specified through the getLogger factory method. If no ResourceBundle or no resource bundle name is found, then it will use the nearest ResourceBundle or resource bundle name inherited from its parent tree. When a ResourceBundle was inherited or specified through the setResourceBundle method, then that ResourceBundle will be used. Otherwise if the logger only has or inherited a resource bundle name, then that resource bundle name will be mapped to a ResourceBundle object, using the default Locale at the time of logging. When mapping resource bundle names to ResourceBundle objects, the logger will first try to use the Thread's context class loader to map the given resource bundle name to a ResourceBundle. If the thread context class loader is null, it will try the system class loader instead. If the ResourceBundle is still not found, it will use the class loader of the first caller of the getLogger factory method. 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 object 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.
Static Constant.
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 Logger.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").
type: java.util.logging.Logger
Static Constant. 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 Logger.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"). type: java.util.logging.Logger
Static Constant.
GLOBAL_LOGGER_NAME is a name for the global logger.
type: java.lang.String
Static Constant. GLOBAL_LOGGER_NAME is a name for the global logger. type: java.lang.String
(*get-anonymous-logger)
(*get-anonymous-logger resource-bundle-name)
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. Changing its parent via the setParent method will still require the security permission specified by that method.
resource-bundle-name - name of ResourceBundle to be used for localizing messages for this logger. May be null if none of the messages require localization. - java.lang.String
returns: a newly created private Logger - java.util.logging.Logger
throws: java.util.MissingResourceException - if the resourceBundleName is non-null and no corresponding resource can be found.
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. Changing its parent via the setParent method will still require the security permission specified by that method. resource-bundle-name - name of ResourceBundle to be used for localizing messages for this logger. May be null if none of the messages require localization. - `java.lang.String` returns: a newly created private Logger - `java.util.logging.Logger` throws: java.util.MissingResourceException - if the resourceBundleName is non-null and no corresponding resource can be found.
(*get-global)
Return global logger object with the name Logger.GLOBAL_LOGGER_NAME.
returns: global logger object - java.util.logging.Logger
Return global logger object with the name Logger.GLOBAL_LOGGER_NAME. returns: global logger object - `java.util.logging.Logger`
(*get-logger name)
(*get-logger name resource-bundle-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 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.
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 - java.lang.String
resource-bundle-name - name of ResourceBundle to be used for localizing messages for this logger. May be null if none of the messages require localization. - java.lang.String
returns: a suitable Logger - java.util.logging.Logger
throws: java.util.MissingResourceException - if the resourceBundleName is non-null and no corresponding resource can be found.
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 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. 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 - `java.lang.String` resource-bundle-name - name of ResourceBundle to be used for localizing messages for this logger. May be null if none of the messages require localization. - `java.lang.String` returns: a suitable Logger - `java.util.logging.Logger` throws: java.util.MissingResourceException - if the resourceBundleName is non-null and no corresponding resource can be found.
(add-handler this handler)
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.
handler - a logging Handler - java.util.logging.Handler
throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
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. handler - a logging Handler - `java.util.logging.Handler` throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
(config this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(entering this source-class source-method)
(entering this source-class source-method param-1)
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.
source-class - name of class that issued the logging request - java.lang.String
source-method - name of method that is being entered - java.lang.String
param-1 - parameter to the method being entered - java.lang.Object
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. source-class - name of class that issued the logging request - `java.lang.String` source-method - name of method that is being entered - `java.lang.String` param-1 - parameter to the method being entered - `java.lang.Object`
(exiting this source-class source-method)
(exiting this source-class source-method result)
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.
source-class - name of class that issued the logging request - java.lang.String
source-method - name of the method - java.lang.String
result - Object that is being returned - java.lang.Object
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. source-class - name of class that issued the logging request - `java.lang.String` source-method - name of the method - `java.lang.String` result - Object that is being returned - `java.lang.Object`
(fine this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(finer this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(finest this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(get-filter this)
Get the current filter for this Logger.
returns: a filter object (may be null) - java.util.logging.Filter
Get the current filter for this Logger. returns: a filter object (may be null) - `java.util.logging.Filter`
(get-handlers this)
Get the Handlers associated with this logger.
returns: an array of all registered Handlers - java.util.logging.Handler[]
Get the Handlers associated with this logger. returns: an array of all registered Handlers - `java.util.logging.Handler[]`
(get-level this)
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.
returns: this Logger's level - java.util.logging.Level
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. returns: this Logger's level - `java.util.logging.Level`
(get-name this)
Get the name for this logger.
returns: logger name. Will be null for anonymous Loggers. - java.lang.String
Get the name for this logger. returns: logger name. Will be null for anonymous Loggers. - `java.lang.String`
(get-parent this)
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.
returns: nearest existing parent Logger - java.util.logging.Logger
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. returns: nearest existing parent Logger - `java.util.logging.Logger`
(get-resource-bundle this)
Retrieve the localization resource bundle for this logger. This method will return a ResourceBundle that was either set by the setResourceBundle method or mapped from the the resource bundle name set via the getLogger factory method for the current default locale. Note that if the result is null, then the Logger will use a resource bundle or resource bundle name inherited from its parent.
returns: localization bundle (may be null) - java.util.ResourceBundle
Retrieve the localization resource bundle for this logger. This method will return a ResourceBundle that was either set by the setResourceBundle method or mapped from the the resource bundle name set via the getLogger factory method for the current default locale. Note that if the result is null, then the Logger will use a resource bundle or resource bundle name inherited from its parent. returns: localization bundle (may be null) - `java.util.ResourceBundle`
(get-resource-bundle-name this)
Retrieve the localization resource bundle name for this logger. This is either the name specified through the getLogger factory method, or the base name of the ResourceBundle set through setResourceBundle method. Note that if the result is null, then the Logger will use a resource bundle or resource bundle name inherited from its parent.
returns: localization bundle name (may be null) - java.lang.String
Retrieve the localization resource bundle name for this logger. This is either the name specified through the getLogger factory method, or the base name of the ResourceBundle set through setResourceBundle method. Note that if the result is null, then the Logger will use a resource bundle or resource bundle name inherited from its parent. returns: localization bundle name (may be null) - `java.lang.String`
(get-use-parent-handlers? this)
Discover whether or not this logger is sending its output to its parent logger.
returns: true if output is to be sent to the logger's parent - boolean
Discover whether or not this logger is sending its output to its parent logger. returns: true if output is to be sent to the logger's parent - `boolean`
(info this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(log this record)
(log this level msg)
(log this level msg param-1)
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.
level - One of the message level identifiers, e.g., SEVERE - java.util.logging.Level
msg - The string message (or a key in the message catalog) - java.lang.String
param-1 - parameter to the message - java.lang.Object
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. level - One of the message level identifiers, e.g., SEVERE - `java.util.logging.Level` msg - The string message (or a key in the message catalog) - `java.lang.String` param-1 - parameter to the message - `java.lang.Object`
(loggable? this level)
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.
level - a message logging level - java.util.logging.Level
returns: true if the given message level is currently being logged. - boolean
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. level - a message logging level - `java.util.logging.Level` returns: true if the given message level is currently being logged. - `boolean`
(logp this level source-class source-method msg)
(logp this level source-class source-method msg param-1)
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.
level - One of the message level identifiers, e.g., SEVERE - java.util.logging.Level
source-class - name of class that issued the logging request - java.lang.String
source-method - name of method that issued the logging request - java.lang.String
msg - The string message (or a key in the message catalog) - java.lang.String
param-1 - Parameter to the log message. - java.lang.Object
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. level - One of the message level identifiers, e.g., SEVERE - `java.util.logging.Level` source-class - name of class that issued the logging request - `java.lang.String` source-method - name of method that issued the logging request - `java.lang.String` msg - The string message (or a key in the message catalog) - `java.lang.String` param-1 - Parameter to the log message. - `java.lang.Object`
(logrb this level source-class source-method bundle-name msg)
(logrb this level source-class source-method bundle-name msg param-1)
Deprecated. Use logrb(java.util.logging.Level, java.lang.String, java.lang.String, java.util.ResourceBundle, java.lang.String, java.lang.Object...) instead
level - One of the message level identifiers, e.g., SEVERE - java.util.logging.Level
source-class - name of class that issued the logging request - java.lang.String
source-method - name of method that issued the logging request - java.lang.String
bundle-name - name of resource bundle to localize msg, can be null - java.lang.String
msg - The string message (or a key in the message catalog) - java.lang.String
param-1 - Parameter to the log message. - java.lang.Object
Deprecated. Use logrb(java.util.logging.Level, java.lang.String, java.lang.String, java.util.ResourceBundle, java.lang.String, java.lang.Object...) instead level - One of the message level identifiers, e.g., SEVERE - `java.util.logging.Level` source-class - name of class that issued the logging request - `java.lang.String` source-method - name of method that issued the logging request - `java.lang.String` bundle-name - name of resource bundle to localize msg, can be null - `java.lang.String` msg - The string message (or a key in the message catalog) - `java.lang.String` param-1 - Parameter to the log message. - `java.lang.Object`
(remove-handler this handler)
Remove a log Handler.
Returns silently if the given Handler is not found or is null
handler - a logging Handler - java.util.logging.Handler
throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
Remove a log Handler. Returns silently if the given Handler is not found or is null handler - a logging Handler - `java.util.logging.Handler` throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
(set-filter this new-filter)
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.
new-filter - a filter object (may be null) - java.util.logging.Filter
throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
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. new-filter - a filter object (may be null) - `java.util.logging.Filter` throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
(set-level this new-level)
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.
new-level - the new value for the log level (may be null) - java.util.logging.Level
throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
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. new-level - the new value for the log level (may be null) - `java.util.logging.Level` throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
(set-parent this 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.
parent - the new parent logger - java.util.logging.Logger
throws: java.lang.SecurityException - if a security manager exists and if the caller does not have LoggingPermission("control").
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. parent - the new parent logger - `java.util.logging.Logger` throws: java.lang.SecurityException - if a security manager exists and if the caller does not have LoggingPermission("control").
(set-resource-bundle this bundle)
Sets a resource bundle on this logger. All messages will be logged using the given resource bundle for its specific locale.
bundle - The resource bundle that this logger shall use. - java.util.ResourceBundle
throws: java.lang.NullPointerException - if the given bundle is null.
Sets a resource bundle on this logger. All messages will be logged using the given resource bundle for its specific locale. bundle - The resource bundle that this logger shall use. - `java.util.ResourceBundle` throws: java.lang.NullPointerException - if the given bundle is null.
(set-use-parent-handlers this use-parent-handlers)
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.
use-parent-handlers - true if output is to be sent to the logger's parent. - boolean
throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
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. use-parent-handlers - true if output is to be sent to the logger's parent. - `boolean` throws: java.lang.SecurityException - if a security manager exists, this logger is not anonymous, and the caller does not have LoggingPermission("control").
(severe this msg)
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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
(throwing this source-class source-method thrown)
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 it is processed specially by output Formatters and is not treated as a formatting parameter to the LogRecord message property.
source-class - name of class that issued the logging request - java.lang.String
source-method - name of the method. - java.lang.String
thrown - The Throwable that is being thrown. - java.lang.Throwable
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 it is processed specially by output Formatters and is not treated as a formatting parameter to the LogRecord message property. source-class - name of class that issued the logging request - `java.lang.String` source-method - name of the method. - `java.lang.String` thrown - The Throwable that is being thrown. - `java.lang.Throwable`
(warning this 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.
msg - The string message (or a key in the message catalog) - java.lang.String
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. msg - The string message (or a key in the message catalog) - `java.lang.String`
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