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Originally published at Internet.comJava Programming, Lecture Notes #1352 * Preface * Preview * Introduction * Discussion * Summary * What's Next -----------------------------------
Preface
This is the second lesson in a miniseries on Java data structures and the Java Collections Framework. The first lesson in the miniseries was entitled Data Structures in Java: Part 1, Getting Started.
The purpose of this miniseries is to help you learn the essential features of Object-Oriented data structures in Java using the Collections Framework.
Supplementary material
I recommend that you also study the other lessons in my extensive collection of online Java tutorials. You will find those lessons published at Gamelan.com. However, as of the date of this writing, Gamelan doesn't maintain a consolidated index of my Java tutorial lessons, and sometimes they are difficult to locate there. You will find a consolidated index at Baldwin's Java Programming Tutorials.
The index on my site provides links to the lessons at Gamelan.com.
Preview
Collection is not only the name of a Java interface, it is also the term given to an object that groups multiple elements into a single unit.
In this lesson, I will discuss how elements are stored in a collection, and why it is often necessary to use a downcast when retrieving and processing those elements...
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