1. Chapter 8
Collection Types

2. Collection
A collection is an object that holds other objects. It is a storage mechanism with operations for adding and removing elements and for accessing and perhaps updating their values.

3. Student Question
Can a collection contain other collections?

4. Collection Interface
The generic Collection interface defines a set of operations that characterize the behavior of most collection classes.

5. Collection Interface (cont’d)

6. Collection Interface (cont’d)

7. Student Question
Why did the methods contains and remove have a parameter of type Object instead of a parameter of the generic type T?
Why does the toArray method return an array of Objects rather than an array of generic type T?