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/**
* Provides the classes and interfaces of
* the Java 2 platform's core logging facilities.
* The central goal of the logging APIs is to support maintaining and servicing
* software at customer sites.
* <P>
* There are four main target uses of the logs:
* </P>
* <OL>
* <LI> <I>Problem diagnosis by end users and system administrators</I>.
* This consists of simple logging of common problems that can be fixed
* or tracked locally, such as running out of resources, security failures,
* and simple configuration errors.
* <LI> <I>Problem diagnosis by field service engineers</I>. The logging information
* used by field service engineers may be considerably more complex and
* verbose than that required by system administrators. Typically such information
* will require extra logging within particular subsystems.
* <LI> <I>Problem diagnosis by the development organization</I>.
* When a problem occurs in the field, it may be necessary to return the captured logging
* information to the original development team for diagnosis. This logging
* information may be extremely detailed and fairly inscrutable. Such information might include
* detailed tracing on the internal execution of particular subsystems.
* <LI> <I>Problem diagnosis by developers</I>. The Logging APIs may also be
* used to help debug an application under development. This may
* include logging information generated by the target application
* as well as logging information generated by lower-level libraries.
* Note however that while this use is perfectly reasonable,
* the logging APIs are not intended to replace the normal debugging
* and profiling tools that may already exist in the development environment.
* </OL>
* <p>
* The key elements of this package include:
* <UL>
* <LI> <I>Logger</I>: The main entity on which applications make
* logging calls. A Logger object is used to log messages
* for a specific system or application
* component.
* <LI> <I>LogRecord</I>: Used to pass logging requests between the logging
* framework and individual log handlers.
* <LI> <I>Handler</I>: Exports LogRecord objects to a variety of destinations
* including memory, output streams, consoles, files, and sockets.
* A variety of Handler subclasses exist for this purpose. Additional Handlers
* may be developed by third parties and delivered on top of the core platform.
* <LI> <I>Level</I>: Defines a set of standard logging levels that can be used
* to control logging output. Programs can be configured to output logging
* for some levels while ignoring output for others.
* <LI> <I>Filter</I>: Provides fine-grained control over what gets logged,
* beyond the control provided by log levels. The logging APIs support a general-purpose
* filter mechanism that allows application code to attach arbitrary filters to
* control logging output.
* <LI> <I>Formatter</I>: Provides support for formatting LogRecord objects. This
* package includes two formatters, SimpleFormatter and
* XMLFormatter, for formatting log records in plain text
* or XML respectively. As with Handlers, additional Formatters
* may be developed by third parties.
* </UL>
* The Logging APIs offer both static and dynamic configuration control.
* Static control enables field service staff to set up a particular configuration and then re-launch the
* application with the new logging settings. Dynamic control allows for updates to the
* logging configuration within a currently running program. The APIs also allow for logging to be
* enabled or disabled for different functional areas of the system. For example,
* a field service engineer might be interested in tracing all AWT events, but might have no interest in
* socket events or memory management.
* <h2>Null Pointers</h2>
* In general, unless otherwise noted in the javadoc, methods and
* constructors will throw NullPointerException if passed a null argument.
* The one broad exception to this rule is that the logging convenience
* methods in the Logger class (the config, entering, exiting, fine, finer, finest,
* log, logp, logrb, severe, throwing, and warning methods)
* will accept null values
* for all arguments except for the initial Level argument (if any).
* <H2>Related Documentation</H2>
* For an overview of control flow,
* please refer to the
* {@extLink logging_overview Java Logging Overview}
* @since 1.4
package java.util.logging;