Packages

• You can store your classes in a package for easier use.
• Think of packages as a library.
• A package name directly corresponds to a directory name.  Each directory name is separated by a period.
• You import packages when you need a class or classes that reside in that package.
• You can either import the entire package, or specify the class or classes you wish to import individually.
• Remember import javax.swing.*; or import javax.swing.JOptionPane; when we used the JOptionPane class?
• Using the * imports all of the classes that reside in that package, but not all of the packages that reside in that package. You need to specify them separately.
• By default, a class can use any other public classes from its own package.
• You are permitted to have classes with the same name in different packages.  This is the only way you can have classes of the same name.
• Having classes of the same name is generally not a good idea.
• If you need both of them in your program, you must specify the package name each time you use them.
• Example: java.util.Date and java.sql.Date are two different classes of the same name.
• To guarantee uniqueness, it is often advisable to use your domain name in reverse.
• package edu.uc.oz.jonesbr would be a good starting package for me.


 More About Packages

Created by:  Brandan Jones January 4, 2002