People collect all sorts of items from bottle caps to exotic cars. For proof, just go to
eBay (www.ebay.com) and see millions and millions of collectibles up for auction.
Now with computers, people amass intangible items such as music files. Exactly
how many MP3 files do you have on your computer? Probably in the hundreds and
you lost track of exactly how many. You may want to develop a custom software, so
you can store the information you want in the format you like, to keep track of all
MP3 files downloaded from the Web.
When we write a program to deal with a collection of items, say, 500 Student
objects, 200 integers, 300 MP3 files, and so forth, simple variables will not work. It
is just not practical or feasible to use 500 variables to process 500 Student objects.
In theory, you can, but honestly, do you want to type in identifiers for 500 variables
(student1, student2, . . .)? A feature supported by programming languages to manipulate
a collection of values is an array.
In this chapter we will learn about Java arrays. We will learn the basics of
array manipulation and how to use different types of arrays properly and effectively.
In addition, we will study several collection classes from the java.util
package that provide more advanced data management features not found in the
basic Java arrays.
