Introduction
Vector/Enumeration
Hashtable,HashMap
   Properties
Collections
Iterator/ArrayList
Generics
Preferences API
  Demo 1
Concurrency Utils
Enumerated Type
Arrays Class
String Tools
  String
  StringBuffer
  StringBuilder
  StringTokenizer
  String.split()
Calendar,Date,Time
  Demo 2
  Demo 3
Other Utilities
Exercises

This chapter concentrates on various useful classes and methods in the java.util package and elsewhere.

Java

• Vector & Enumeration - - unlike an array, Vector objects contain a list of objects that can grow or shrink. The Enumeration cycles once through each item in a list such as a Vector.
  
  
• Hashtable, HashMap and Properties - associative arrays of objects that use key/value pairs
  
  
• Collections Framework - other classes and interfaces dealing with collections of objects.
  
  
• Iterator & ArrayList - Iterator offers an improved tool over Enumeration for cycling through each item in a list such as an a ArrayList. The latter class is similar to Vector but faster due to no synchronization.
  
  
• Generics - new capability added in J2SE5.0 in which the collections classes can be restricted at compile-time to a particular class type rather than only Object.
  
  
• Preferences API - the java.util.prefs package contains a set of classes that supports a program's user preference record-keeping.
  
  
• Concurrency Utilities in J2SE5.0 - enhanced tools added with J2SE5.0 for dealing efficiently with threads.
  
  
• Enumerated Types in J2SE5.0 - new capability in J2SE5.0 for defiining a special enum type that only takes the values of a specified set of constants.
  
  
• Arrays Class - lots of methods for dealing with arrays such as searching and sorting.
  
  
• String tools: - discussion of various tools for manipulating strings
  • String class
  • StringBuffer - efficiently build strings
    
  • StringBuilder - improved tool for building strings
  • StringTokenizer - search and parse strings
  • String.split () - better alternative to StringTokenizer
    
    
• Date, Calendar and Time - methods for date/time handling
  
  
• Other Utilities - other utilities including more classes and sub-packages of java.util.
  
  
• Exercises

Supplements

• Performance in Java

Tech

• Recursion - review the recursion programming technique.
  
• ArbitaryPrecision - the java.math package provides two classes that can represent integers of arbitary length and decimals with fractions of arbitrary width.
  
  • BigInteger
    
  • BigDecimal
    
• Bit Handling - we review the various tools in Java for accessing and modifying bits in number representations.
• Exercises

Physics

• Data Gen&Analysis
  
  • Demo 1
    
  • Demo 2
    
• Exercises

Latest update: Nov. 19, 2004

              Tech
ArbitaryPrecision
   BigInteger
   BigDecimal
Bit Handling
Exercises

           Physics
Data Gen&Analysis
  Demo 1
  Demo 2
Exercises