This document provides an introduction to and overview of the ArrayList class in Java. It discusses how ArrayLists allow for dynamic sizes unlike arrays and can store an unlimited number of objects. It also contains an example of creating and using an ArrayList to store String objects and compares the key differences between arrays and ArrayLists. The document was prepared by Mahmoud Rafeek Al-farra and includes links to additional resources on ArrayLists.

1. using Java
2015
Data Structure
Prepared by: Mahmoud Rafeek Al-farra
in Java
5. Array List

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Contents
Example
The ArrayList Class
Introduction
Comparison between Arrays and ArrayList

3. Introduction
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You can create an array to store objects. But, once
the array is created, its size is fixed.
Nevertheless, you can still use arrays to implement
dynamic data structures.
 The trick is to create a larger new array to replace
the current array, if the current array cannot hold new
elements in the list.

4. Introduction
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You can see an animated example from the following link:
http://www.cs.armstrong.edu/liang/animation/web/ArrayList.html

5. The ArrayList Class
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Java provides the ArrayList class, which can be used to
store an unlimited number of objects.
ArrayList is known as a generic class with a generic type E.
You can specify a concrete type to replace E when creating
an ArrayList.
For example:
ArrayList <String> cities = new ArrayList<> ();

6. The ArrayList Class
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7. Example: The ArrayList Class
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8. Example: The ArrayList Class
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9. Comparison between Arrays and ArrayList
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10. Array List
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The ArrayList is in the java.util package, it is imported in line 1.
Case Study: Develop a program that prompts the user to enter a
sequence of numbers and displays the distinct numbers in the
sequence. Assume that the input ends with 0 and 0 is not counted
as a number in the sequence. [ind, N.W]

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2015
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