Question 1

Which of the following is false?

Accepted Answer

A)  You should not call overridable methods from constructors-when creating a subclass object, this could lead to an overridden method being called before the subclass object is fully initialized. 
B)  It's OK to any of a class's methods from its constructors. 
C)  When you construct a subclass object, its constructor first calls one of the direct superclass's constructors. If the superclass constructor calls an overridable method, the subclass's version of that method will be called by the superclass constructor. 
D)  It's acceptable to call a static method from a constructor. 
A)  You should not call overridable methods from constructors-when creating a subclass object, this could lead to an overridden method being called before the subclass object is fully initialized. 
B)  It's OK to any of a class's methods from its constructors. 
C)  When you construct a subclass object, its constructor first calls one of the direct superclass's constructors. If the superclass constructor calls an overridable method, the subclass's version of that method will be called by the superclass constructor. 
D)  It's acceptable to call a static method from a constructor.

Question 2

Classes and methods are declared final for all but the following reasons:

Accepted Answer

A)  final methods allow inlining the code. 
B)  final methods and classes prevent further inheritance. 
C)  final methods are static. 
D)  final methods can improve performance. 
A)  final methods allow inlining the code. 
B)  final methods and classes prevent further inheritance. 
C)  final methods are static. 
D)  final methods can improve performance.

Question 3

Every object in Java knows its own class and can access this information through method .

Accepted Answer

A)  getClass. 
B)  getInformation. 
C)  objectClass. 
D)  objectInformation. 
A)  getClass. 
B)  getInformation. 
C)  objectClass. 
D)  objectInformation.

Question 4

Polymorphism enables you to:

Accepted Answer

A)  program in the general. 
B)  program in the specific. 
C)  absorb attributes and behavior from previous classes. 
D)  hide information from the user. 
A)  program in the general. 
B)  program in the specific. 
C)  absorb attributes and behavior from previous classes. 
D)  hide information from the user.

Question 5

All of the following methods are implicitly final except:

Accepted Answer

A)  a method in an abstract class. 
B)  a private method. 
C)  a method declared in a final class. 
D)  static method. 
A)  a method in an abstract class. 
B)  a private method. 
C)  a method declared in a final class. 
D)  static method.

Question 6

In Java SE 7 and earlier, an interface may contain:

Accepted Answer

A)  private static data and public abstract methods. 
B)  only public abstract methods. 
C)  public static final data and public abstract methods. 
D)  private static data and public final methods. 
A)  private static data and public abstract methods. 
B)  only public abstract methods. 
C)  public static final data and public abstract methods. 
D)  private static data and public final methods.

Question 7

Which of the following statements is false?

Accepted Answer

A)  References to interface types do not have access to method toString. 
B)  Method toString can be invoked implicitly on any object. 
C)  With inheritance, classes and their inherited classes tend to be very similar. 
D)  Dramatically different classes can often meaningfully implement the same interface. 
A)  References to interface types do not have access to method toString. 
B)  Method toString can be invoked implicitly on any object. 
C)  With inheritance, classes and their inherited classes tend to be very similar. 
D)  Dramatically different classes can often meaningfully implement the same interface.

Question 8

Which of the following statements is false?

Accepted Answer

A)  Prior to Java SE 8, it was common to associate with an interface a class containing static helper methods for working with objects that implemented the interface. 
B)  Class Collections contains many static helper methods for working with objects that implement interfaces Collection, List, Set and more. 
C)  Collections method sort can sort objects of any class that implements interface List. 
D)  With non-static interface methods, helper methods can now be declared directly in interfaces rather than in separate classes. 
A)  Prior to Java SE 8, it was common to associate with an interface a class containing static helper methods for working with objects that implemented the interface. 
B)  Class Collections contains many static helper methods for working with objects that implement interfaces Collection, List, Set and more. 
C)  Collections method sort can sort objects of any class that implements interface List. 
D)  With non-static interface methods, helper methods can now be declared directly in interfaces rather than in separate classes.

Question 9

A(n) class cannot be instantiated.

Accepted Answer

A)  final. 
B)  concrete. 
C)  abstract. 
D)  polymorphic. 
A)  final. 
B)  concrete. 
C)  abstract. 
D)  polymorphic.

Question 10

Which of the following statements is false?

Accepted Answer

A)  In Java SE 8, an interface may declare default methods-that is, public methods with concrete implementations that specify how an operation should be performed. 
B)  When a class implements an interface, the class receives the interface's default concrete implementations if it does not override them. 
C)  When you enhance an existing interface with default methods-any class that implemented the original interface will break. 
D)  With default methods, you can declare common method implementations in interfaces (rather than abstract classes), which gives you more flexibility in designing your classes. 
A)  In Java SE 8, an interface may declare default methods-that is, public methods with concrete implementations that specify how an operation should be performed. 
B)  When a class implements an interface, the class receives the interface's default concrete implementations if it does not override them. 
C)  When you enhance an existing interface with default methods-any class that implemented the original interface will break. 
D)  With default methods, you can declare common method implementations in interfaces (rather than abstract classes), which gives you more flexibility in designing your classes.

Which of the following is false?

Classes and methods are declared final for all but the following reasons:

Every object in Java knows its own class and can access this information through method .

Polymorphism enables you to:

All of the following methods are implicitly final except:

In Java SE 7 and earlier, an interface may contain:

Which of the following statements is false?

Which of the following statements is false?

A(n) class cannot be instantiated.

Which of the following statements is false?

Introduction to Computers and Java

Introduction to Java Applications

Control Statements

Control Statements

Methods

Arrays and Arraylists

Introduction to Classes and Objects

Classes and Objects: a Deeper Look

Object Oriented Programming: Inheritance

Exception Handling

Gui Components

Graphics and Java 2D

Fundamentals of Characters and Strings

Files, Streams and Object Serialization

Generic Collections

Lambdas

Recursion

Searching, Sorting and Big O

Generic Classes and Methods

Custom Generic Data Structures

GUI

Concurrency

Accessing Databases With JDBC

JavaFX

Filters

Exam 10: Object-Oriented Programming: Polymorphism

Which of the following is false?

Classes and methods are declared final for all but the following reasons:

Every object in Java knows its own class and can access this information through method .

Polymorphism enables you to:

All of the following methods are implicitly final except:

In Java SE 7 and earlier, an interface may contain:

Which of the following statements is false?

Which of the following statements is false?

A(n) class cannot be instantiated.

Which of the following statements is false?

Introduction to Computers and Java

Introduction to Java Applications

Control Statements

Control Statements

Methods

Arrays and Arraylists

Introduction to Classes and Objects

Classes and Objects: a Deeper Look

Object Oriented Programming: Inheritance

Exception Handling

Gui Components

Graphics and Java 2D

Fundamentals of Characters and Strings

Files, Streams and Object Serialization

Generic Collections

Lambdas

Recursion

Searching, Sorting and Big O

Generic Classes and Methods

Custom Generic Data Structures

GUI

Concurrency

Accessing Databases With JDBC

JavaFX

Filters