Question 17 (12 points)

Saved

When the following code is run, which of the following exceptions could occur if the precondition is met? (2 points)

// precondition: a is NOT null public String doSomething(ArrayList a, int b) { int i; String s;

for(i = 0; i < a.size(); i++) { s = (String)(a.get(i)); if(s.length() == b) { return s; } } return null; }

Question 17 options:

1)	ArithmeticException

2)	ArrayIndexOutOfBoundsException

3)	ClassCastException

4)	IndexOutOfBoundsException

5)	NullPointerException

Question 18 (12 points)

Saved

Assume a two-dimensional array is declared as follows:

int arr[][] = {1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12};

Which of these statements are true? (2 points)

I. arr.length is 3 II. arr[0].length is 4 III. arr[2][3] is 12

Question 18 options:

1)

I only

2)

II only

3)

III only

4)	I and III only

5)	I, II, and III

Question 19 (12 points)

Saved

What is stored in the array arr after the following code executes? (2 points)

int[ ] arr = {17, 34, 43, 71}; int i = 0; while(i < arr.length) { if((arr[i] % 2) == 1) { arr[i] = arr[i] % 3; } else { arr[i] = arr[i] / 3; } i++; }

Question 19 options:

1)	{1, 11, 2, 10}

2)	{2, 10, 11, 1}

3)	{2, 11, 1, 2}

4)	{2, 11, 1, 10}

5)	An ArrayIndexOutOfBoundsException occurs.

Question 20 (12 points)

Saved

Suppose you write a subclass of Insect named Ant. You add a new method named doSomething to the Ant class. You write a client class that instantiates an Antobject and invokes the doSomething method. Which of the following Antdeclarations will permit this? (2 points)

I. Insect a = new Ant(); II. Ant a = new Ant(); III. Ant a = new Insect();

Question 20 options:

1)

I only

2)

II only

3)

III only

4)	I and II only

5)	I, II, and III only