Java Util Package - Utility Package of Java

Java Utility package is one of the most commonly used packages in the java program. The Utility Package of Java consist of the following components:

• collections framework
  
• legacy collection classes
    
• event model
    
• date and time facilities
    
• internationalization
    
• miscellaneous utility classes such as string tokenizer, random-number generator and bit array
    

Here are some of the description of the utility classes of this package:

Date  
The Date class is used to manipulate calendar dates in a system-independent fashion. 

StringTokenizer  
This StringTokenizer class is used to convert a String of text into its tokens. 

Properties  
The properties table contains key/value pairs where both the key and the value are Strings and the class is used by the System class to implement System properties. 

Observer and Observable  
Classes that implement the Observer interface can "watch" Observable objects for state changes. When an Observable object changes it notifies all of its Observers of the change. 

Random-Number Generator  
The Random Number Generator class is used to generate the random-numbers. 

Enumeration  
The Enumeration interface defines a generic programming interface for iterating through a set of values.