Test 2 Prep 3 Questions

Question 1

True/False: A class can only implement one interface.

Answer 1

False

Question 2

Java interfaces are allowed to have _ instance variables?

Answer 2

Zero, although can have final variables.

Question 3

True/False: The following will compile:

Comparable aBlock = new String();

Answer 3

True

Question 4

What is the visibility of the method below?

public interface myChoice {
    void shoutOutLoud(T phrase);
}

Answer 4

public

Question 5

Will the following compile?

public interface myName {
    String whatsMyName(String name) {
        return "Harsh";
    }
}

Answer 5

Will not compile

Question 6

True/False: ArrayList implements at least one interface.

Answer 6

True

Question 7

True/False: The following code will compile:
List myNums = new ArrayList();

Answer 7

False

Question 8

True/False: The following will compile:

Comparable aBlock = new Comparable();

Answer 8

False

Question 9

What line causes the following code to fail to compile?

List myInts = new ArrayList();
myInts.add(4);
myInts.add(new Integer(42));
int firstInt = myInts.get(0);

Answer 9

The last line.

Question 10

Given an interface Gradeable and a class named CS Test, write the class declaration (first line) for the CSTest so that CSTest will use Gradeable.

Answer 10

public class CSTest implements Gradeable, Comparable,... {
}