Enhancements in Packages java.lang.* and java.util.*
Version 1.3 of the Java 2 SDK includes the following enhancements:Classes java.lang.Math and java.lang.StrictMath
New Timer API
Enhanced Collections Framework
Virtual Machine Shutdown Hooks
New URL JAR File Caching
Classes java.lang.Math and java.lang.StrictMathThe Java 2 Platform now contains two clases which provide API for performing general numeric operations.
- java.lang.StrictMath - Class java.lang.StrictMath has the same API as old class java.lang.Math, which was present previous versions of the Java platform. Unlike class Math, however, StrictMath is defined to return bit-for-bit reproducible results in all implementations.
- java.lang.Math - Class java.lang.Math provides the same set of API as does class StrictMath. However, unlike some of the numeric functions of class StrictMath, all implementations of the equivalent functions of class Math are not defined to return the bit-for-bit same results, but can vary within specified constraints. This permits better-performing implementations where strict reproducibility is not required.
New Timer APITwo new classes have been added to the Java 2 Platform to provide an API for a timer facility which can be used for purposes such as animations, human interaction timeouts, on-screen clocks and calendars, work-scheduling routines, reminder facilities, and more.
Enhanced Collections FrameworkThe Collections Framework has these new convenience APIs:
The following special-purpose implementation has also been added:
- Added java.util.Collections.singletonList and java.util.Collections.singletonMap. Previously, there was a convenience implementation for singleton Set, but no corresponding implementation for List and Map. Both of these implementations proved desirable in practice.
- Added java.util.Collections.EMPTY_MAP. Previously, there were constant convenience implementations for the empty Set and List, but no corresponding implementation for Map.
Virtual Machine Shutdown HooksSophisticated applications often require the ability to perform specific actions when the virtual machine shuts down, whether due to voluntary exit or involuntary termination. Typical actions include cleanly closing down network connections, saving session state, and deleting temporary files. Every major operating system provides the means for native applications to do this, though of course the details vary from platform to platform. Three methods have been added to java.lang.Runtime to provide a simple and portable interface to these facitilies. The new methods are:
New URL JAR File CachingThe API of classes java.util.zip and java.util.jar have been enhanced with the addition of the following:
Please send comments to: firstname.lastname@example.org