Implementing a Collection Class - Building Java Programs: A Back to Basics Approach - page 883

Chapter 15

Implementing
a Collection Class

Introduction

15.1 Simple ArrayIntList
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Adding and Printing

In Chapters 10 and 11 we saw how to use various data structures that
are part of the collections framework.As a Java programmer, you will find
it useful to have these off-the-shelf solutions available to you, but you can
learn a lot from examining how these structures are implemented. In this
chapter we will explore in detail how to implement one such structure.

Thinking about Encapsulation

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Dealing with the Middle of the
List

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Another Constructor and a
Constant

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Preconditions and
Postconditions

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Our goal is to understand the ArrayList class that was described in
detail in Chapter 10. Recall that ArrayList is a generic class that is best
described as ArrayList<E> , where E is filled in with a specific element
type. Because generic classes are not easy to implement, we will first
explore the implementation of a class called ArrayIntList that can be
used to store a list of simple integer values.There aren't a lot of applica-
tions for a simple ArrayIntList object, but the code we write for it will
be similar to the code we need for the generic version.The chapter ends
with a section that explores how to turn the more specific
ArrayIntList into a generic ArrayList<E> .

15.2 A More Complete
ArrayIntList

Throwing Exceptions

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Convenience Methods

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15.3 Advanced Features
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Resizing When Necessary

Adding an Iterator

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15.4 ArrayList<E>

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