diff -r fd16c54261b3 -r 90ce3da70b43 jdk/src/share/classes/java/util/logging/package.html --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/util/logging/package.html Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,134 @@ + + + + + + + +

+Provides the classes and interfaces of +the JavaTM 2 + platform's core logging facilities. +The central goal of the logging APIs is to support maintaining and servicing +software at customer sites. + +

+There are four main target uses of the logs: +

+ +
    +
  1. Problem diagnosis by end users and system administrators. + 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. + +
  2. Problem diagnosis by field service engineers. 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. + +
  3. Problem diagnosis by the development organization. + 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. + +
  4. Problem diagnosis by developers. 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. +
+ +

+The key elements of this package include: + +

+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. +

+ +

Null Pointers

+

+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). +

+

Related Documentation

+

+For an overview of control flow, +please refer to the + +Java Logging Overview. +

+ + + +@since 1.4 + + + + + + + + +