Chapter 9 - Multiple Choice Flashcards
1
Q
- What is/are the valid way(s) to declare a two-dimensional integer array named a? (Check all that apply.)
❑ int [ ][ ] a;
❑ int a [ ][ ];
❑ array [ ] int a;
❑ int array [ ] a;
A
int[ ][ ] a; and int a[ ][ ];
2
Q
- A two-dimensional array is an array of arrays.
❑ true
❑ false
A
true
3
Q
- In a two-dimensional array, every row must have the same number of columns.
❑ true
❑ false
A
false
4
Q
- What is the default value of the elements of a two-dimensional array of booleans after declaration and instantiation of the array?
❑ true
❑ false
❑ undefined
A
false
5
Q
- How do you access the element of array a located at row 2 and column 4?
❑ a{2}{4}
❑ a( 2,4 )
❑ a[2][4]
❑ a[4][2]
A
a[2][4]
6
Q
- How do you retrieve the number of rows in a two-dimensional array a?
❑ a.rows
❑ a.length
❑ a.rows( )
❑ a.size
A
a.length
7
Q
- How do you retrieve the number of columns in row 2 in a two-dimensional array a?
❑ a.length
❑ a[2].length
❑ a.size
❑ a[2].size
A
a[2].length
8
Q
- All the elements of a two-dimensional array must be of the same type.
❑ true
❑ false
A
true
9
Q
- An ArrayList can be returned by a method.
❑ true
❑ false
A
true
10
Q
- It is possible to declare and instantiate an ArrayList of a user-defined class type.
❑ true
❑ false
A
true
11
Q
- As we add objects to an ArrayList, how can we be sure it has enough capacity?
❑ Use the setCapacity method.
❑ Use the trimToSize method.
❑ We don’t need to do anything; capacity expands automatically as needed.
A
We don’t need to do anything; capacity expands automatically as needed
12
Q
- Where does the add method of the ArrayList class add an object?
❑ at the beginning of the list
❑ at the end of the list
A
at the end of the list
13
Q
- To what package does the class ArrayList belong?
❑ java.io
❑ java.util
❑ java.array
❑ java.list
A
java.util
