Question 1

Which of the following is an example of a functional interface, having a single abstract method?

Accepted Answer

A) ActionListener 
B) KeyListener 
C) MouseListener 
D) MouseAdapter 
A) ActionListener 
B) KeyListener 
C) MouseListener 
D) MouseAdapter A

Question 2

Which of the following statements about the Object.clone method is NOT true?

Accepted Answer

A) Its return type is the same as the cloned object. 
B) It returns a new object that has a state identical to the cloned object. 
C) If the object being cloned does not implement the Cloneable interface, then it throws an exception. 
D) It does not clone mutable instance variables. 
A) Its return type is the same as the cloned object. 
B) It returns a new object that has a state identical to the cloned object. 
C) If the object being cloned does not implement the Cloneable interface, then it throws an exception. 
D) It does not clone mutable instance variables. A

Question 3

The methods of an ____ describe the actions to be taken when an event occurs.

Accepted Answer

A) event source 
B) event interface 
C) action source 
D) event listener 
A) event source 
B) event interface 
C) action source 
D) event listener D

Question 4

Which of the following is true about a default method in an interface declaration?

Accepted Answer

A) A default method is a static method that does not have an implicit parameter. 
B) A default method does not provide an implementation. 
C) A class that implements the interface cannot override the default behavior. 
D) A class that implements the interface can inherit the default behavior. 
A) A default method is a static method that does not have an implicit parameter. 
B) A default method does not provide an implementation. 
C) A class that implements the interface cannot override the default behavior. 
D) A class that implements the interface can inherit the default behavior.

Question 5

Consider the following code snippet:   Which of the following statements will complete this code?

Accepted Answer

A) java.swing.event.ActionEvent;. 
B) javax.awt.event.ActionEvent; 
C) java.awt.event.ActionEvent; 
D) javax.swing.event.ActionEvent; 
A) java.swing.event.ActionEvent;. 
B) javax.awt.event.ActionEvent; 
C) java.awt.event.ActionEvent; 
D) javax.swing.event.ActionEvent;

Question 6

Consider the following code snippet:   What is wrong with this code?

Accepted Answer

A) There is nothing wrong with this code. 
B) The class has implemented the wrong interface. 
C) repaint() method was not called. 
D) The mouseClicked method cannot access the x and y coordinates of the mouse. 
A) There is nothing wrong with this code. 
B) The class has implemented the wrong interface. 
C) repaint() method was not called. 
D) The mouseClicked method cannot access the x and y coordinates of the mouse.

Question 7

Which of the following statements about an inner class is true?

Accepted Answer

A) An inner class may not be declared within a method of the enclosing scope. 
B) The methods of an inner class can access variables declared in the enclosing scope. 
C) An inner class may only be declared within a method of the enclosing scope. 
D) An inner class can access variables from the enclosing scope only if they are passed as constructor or method parameters. 
A) An inner class may not be declared within a method of the enclosing scope. 
B) The methods of an inner class can access variables declared in the enclosing scope. 
C) An inner class may only be declared within a method of the enclosing scope. 
D) An inner class can access variables from the enclosing scope only if they are passed as constructor or method parameters.

Question 8

When you use a timer, you need to define a class that implements the ____ interface.

Accepted Answer

A) TimerListener 
B) TimerActionListener 
C) ActionListener 
D) StartTimerListener 
A) TimerListener 
B) TimerActionListener 
C) ActionListener 
D) StartTimerListener

Question 9

Consider the following code snippet:   Which statement would add the panel to the frame?

Accepted Answer

A) frame.add(JPanel panel); 
B) frame.addComponent(JPanel panel); 
C) frame.add(panel); 
D) frame.addComponent(panel); 
A) frame.add(JPanel panel); 
B) frame.addComponent(JPanel panel); 
C) frame.add(panel); 
D) frame.addComponent(panel);

Question 10

Consider the following class:   Which of the following method headers should be used to complete the ClickListener class?

Accepted Answer

A) public void actionPerformed(ActionEvent event) 
B) public void actionPerformed(ClickListener event) 
C) public void actionPerformed() 
D) public void actionPerformed(ActionListener event) 
A) public void actionPerformed(ActionEvent event) 
B) public void actionPerformed(ClickListener event) 
C) public void actionPerformed() 
D) public void actionPerformed(ActionListener event)

Question 11

In UML, a dotted arrow with a triangular tip denotes ____________________.

Accepted Answer

A) interface implementation 
B) dependency 
C) inheritance 
D) aggregation 
A) interface implementation 
B) dependency 
C) inheritance 
D) aggregation

Question 12

What does the MouseAdapter class provide?

Accepted Answer

A) A class can implement the MouseAdapter class to handle mouse events. 
B) The MouseAdapter class allows your program to accept input from multiple mice. 
C) The MouseAdapter class implements all of the methods of the MouseListener interface as do-nothing methods, eliminating the need to provide an implementation for all 5 methods of the MouseListener interface. 
D) The MouseAdapter class implements all of the methods of the ActionListener interface as do-nothing methods, eliminating the need to implement the ActionListener interface. 
A) A class can implement the MouseAdapter class to handle mouse events. 
B) The MouseAdapter class allows your program to accept input from multiple mice. 
C) The MouseAdapter class implements all of the methods of the MouseListener interface as do-nothing methods, eliminating the need to provide an implementation for all 5 methods of the MouseListener interface. 
D) The MouseAdapter class implements all of the methods of the ActionListener interface as do-nothing methods, eliminating the need to implement the ActionListener interface.

Question 13

Consider the following class:   Which is the best statement to use to complete the compareTo() method?

Accepted Answer

A) return Integer.compare(otherTemp.value, value) 
B) return (value - otherTemp.value) 
C) return (otherTemp.value - value) 
D) return Integer.compare(value, otherTemp.value) 
A) return Integer.compare(otherTemp.value, value) 
B) return (value - otherTemp.value) 
C) return (otherTemp.value - value) 
D) return Integer.compare(value, otherTemp.value)

Question 14

Suppose you are writing an interface called Resizable, which includes one void method called resize that accepts no parameters. public interface Resizable
{
_______________________
}
Which of the following can be used to complete the interface declaration correctly?

Accepted Answer

A) protected void resize(); 
B) void resize(); 
C) private void resize(); 
D) public void resize() {
System.out.println("resizing ..."); } 
A) protected void resize(); 
B) void resize(); 
C) private void resize(); 
D) public void resize() {
System.out.println("resizing ..."); }

Question 15

Consider the following code snippet:   Which of the following statements is correct?

Accepted Answer

A) A ClickListener object has been added as a listener for the action events that buttons generate. 
B) Class ClickListener is an interface type. 
C) Class ButtonTester implements an interface type. 
D) Class ButtonTester is an interface type. 
A) A ClickListener object has been added as a listener for the action events that buttons generate. 
B) Class ClickListener is an interface type. 
C) Class ButtonTester implements an interface type. 
D) Class ButtonTester is an interface type.

Question 16

Which of the following statements about events and graphical user interface programs is true?

Accepted Answer

A) Your program must instruct the Java window manager to send it notifications about specific types of events to which the program wishes to respond. 
B) The Java window manager will automatically send your program notifications about all events that have occurred. 
C) Your program must override the default methods to handle events. 
D) Your program must respond to notifications of all types of events that are sent to it by the Java window manager. 
A) Your program must instruct the Java window manager to send it notifications about specific types of events to which the program wishes to respond. 
B) The Java window manager will automatically send your program notifications about all events that have occurred. 
C) Your program must override the default methods to handle events. 
D) Your program must respond to notifications of all types of events that are sent to it by the Java window manager.

Question 17

The ____ class in the javax.swing package generates a sequence of events, spaced apart at even time intervals.

Accepted Answer

A) Clock 
B) TimeClock 
C) Timer 
D) StopWatch 
A) Clock 
B) TimeClock 
C) Timer 
D) StopWatch

Question 18

Which of the following statements about a mock class is true?

Accepted Answer

A) A mock class does not provide an implementation of the services of the actual class. 
B) A mock class must be an interface. 
C) A mock class provides a simplified implementation of the services of the actual class. 
D) A mock class provides a complete implementation of the services of the actual class. 
A) A mock class does not provide an implementation of the services of the actual class. 
B) A mock class must be an interface. 
C) A mock class provides a simplified implementation of the services of the actual class. 
D) A mock class provides a complete implementation of the services of the actual class.

Question 19

Which of the following statements about an interface is true?

Accepted Answer

A) An interface has both public and private methods. 
B) An interface has methods and instance variables. 
C) An interface has methods but no instance variables. 
D) An interface has neither methods nor instance variables. 
A) An interface has both public and private methods. 
B) An interface has methods and instance variables. 
C) An interface has methods but no instance variables. 
D) An interface has neither methods nor instance variables.

Question 20

A class that implements an interface must provide an implementation for all ____ methods.

Accepted Answer

A) private 
B) final 
C) static 
D) abstract 
A) private 
B) final 
C) static 
D) abstract

Exam 10: Interfaces

Which of the following is an example of a functional interface, having a single abstract method?

Which of the following statements about the Object.clone method is NOT true?

The methods of an ____ describe the actions to be taken when an event occurs.

Which of the following is true about a default method in an interface declaration?

Consider the following code snippet: Which of the following statements will complete this code?

Consider the following code snippet: What is wrong with this code?

Which of the following statements about an inner class is true?

When you use a timer, you need to define a class that implements the ____ interface.

Consider the following code snippet: Which statement would add the panel to the frame?

Consider the following class: Which of the following method headers should be used to complete the ClickListener class?

In UML, a dotted arrow with a triangular tip denotes ____________________.

What does the MouseAdapter class provide?

Consider the following class: Which is the best statement to use to complete the compareTo() method?

Suppose you are writing an interface called Resizable, which includes one void method called resize that accepts no parameters. public interface Resizable { _______________________ } Which of the following can be used to complete the interface declaration correctly?

Consider the following code snippet: Which of the following statements is correct?

Which of the following statements about events and graphical user interface programs is true?

The ____ class in the javax.swing package generates a sequence of events, spaced apart at even time intervals.

Which of the following statements about a mock class is true?

Which of the following statements about an interface is true?

A class that implements an interface must provide an implementation for all ____ methods.

Introduction

Using Objects

Implementing Classes

Fundamental Data Types

Decisions

Loops

Arrays and Array Lists

Designing Classes

Inheritance

Input/Output and Exception Handling

Object-Oriented Design

Recursion

Sorting and Searching

The Java Collections Framework

Basic Data Structures

Tree Structures

Generic Classes

Stream Processing

Graphical User Interfaces

Advanced Input/Output

Multithreading

Internet Networking

Relational Databases

XML

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