Object Oriented Design Midterm

Front 1

Which method must be defined by a class implementing the java.lang.Runnable interface and serves as the path of execution for all threads?

Back 1

run()

Front 2

The following classes are defined in a program:

class Base {

public void show() {

System.out.println("show() in Base called"); }}

class Derived extends Base {

public void show() {

System.out.println("show() in Derived called");

}

}

What will be displayed when the following code is executed?

Base b = new Derived();

b.show();

Back 2

show() in Derived called

Front 3

The code in a thread that is different than the main/UI thread should directly manipulate user interface elements?

Back 3

False

Front 4

Each method in a class must have a unique name.

Back 4

False

Front 5

All interface methods must be declared as public when implemented in a clas

Back 5

True

Front 6

What method in the Thread class do you call to make the current thread cease executing for a specified amount of time?

Back 6

sleep()

Front 7

A Java class can implement _____________ interface(s).

Back 7

one or more than one

Front 8

To create an InputStream to read from a file on a Web server, you use the method __________ in the URL class.

Back 8

openStream();

Front 9

What is used to declare a class named A with two generic types?

Back 9

public class A { ... },>

Front 10

What create and starts a thread?

Back 10

new Thread(new MyRunnable()).start();

Front 11

java.util.ArrayList list = new java.util.ArrayList<>();

list.add("Apple");

java.util.ArrayList list2 = list;list.add("Banana"); list2.add("Orange");

System.out.println(list2);

what is printed?

Back 11

[Apple, Banana, Orange]

Front 12

What exception is thrown by the read() method of InputStream class?

Back 12

IOException

Front 13

What is object serialization?

Back 13

Converting an object into a stream of bytes in order to store or transmit the object.

Front 14

What is an example of a class that cannot be extended?

Back 14

final class A { }

Front 15

What is the name of the method used to initiate execution of a thread?

Back 15

start()