Self-Assessment Exercises
Chapter 12:
Collections
1.
Java collections are divided into two main groups: ________ and ________.
a.
primitive collections, object collections
b.
simple collections, maps
c.
simple collections, complex collections
d.
Array
s,
ArrayList
s
2.
The number of elements in the collection
myCollection
can be obtained with which of the following expressions?
a.
myCollection.length
b.
myCollection.length()
c.
myCollection.size()
d.
size(myCollection)
3.
Assume that you have created an
ArrayList
named
myList
and that you have stored ten
Color
objects in it. What is the return type of
myList.get(4)
? "
a.
boolean
b.
int
c.
Color
d.
Object
4.
Suppose that you create an
ArrayList
with the statement:
ArrayList myList = new ArrayList();
What can be stored as elements in
myList
?
a.
only primitive types
b.
only non-primitive types
c.
only objects of type
ArrayList
d.
only objects of type
Object
5.
Which of the following statements would you use to store the string
“A”
at index 2 in the
ArrayList myList
?
a.
myList.set(2, "A");
b.
myList.indexOf(2) = "A";
c.
myList[2] = "A";
d.
set(myList, 2, "A");
