Question 1

You must call most methods other than ________ explicitly to tell them to perform their tasks.

Accepted Answer

A)  public methods 
B)  main 
C)  static methods 
D)  private methods 
A)  public methods 
B)  main 
C)  static methods 
D)  private methods B

Question 2

Which of the following statements is false?

Accepted Answer

A)  The javac command can compile multiple classes at once; simply list the source-code filenames after the command with each filename separated by a comma from the next. 
B)  If the directory containing the app includes only one app's files, you can compile all of its classes with the command javac *.java. 
C)  The asterisk (*) in javac *.java indicates that all files in the current directory ending with the filename extension ".java" should be compiled. 
D)  All of the above are true. 
A)  The javac command can compile multiple classes at once; simply list the source-code filenames after the command with each filename separated by a comma from the next. 
B)  If the directory containing the app includes only one app's files, you can compile all of its classes with the command javac *.java. 
C)  The asterisk (*) in javac *.java indicates that all files in the current directory ending with the filename extension ".java" should be compiled. 
D)  All of the above are true. A

Question 3

Which of the following statements is false?

Accepted Answer

A)  By convention class names begin with an uppercase letter, and method and variable names begin with a lowercase letter. 
B)  Instance variables exist before methods are called on an object, while the methods are executing and after the methods complete execution. 
C)  A class normally contains one or more methods that manipulate the instance variables that belong to particular objects of the class. 
D)  Instance variables can be declared anywhere inside a class. 
A)  By convention class names begin with an uppercase letter, and method and variable names begin with a lowercase letter. 
B)  Instance variables exist before methods are called on an object, while the methods are executing and after the methods complete execution. 
C)  A class normally contains one or more methods that manipulate the instance variables that belong to particular objects of the class. 
D)  Instance variables can be declared anywhere inside a class. D

Question 4

Which of the following statements is false?

Accepted Answer

A)  In the UML, each class is modeled in a class diagram as a rectangle with three compartments. The top one contains the class's name centered horizontally in boldface. The middle one contains the class's attributes, which correspond to instance variables in Java. The bottom one contains the class's operations, which correspond to methods and constructors in Java. 
B)  UML represents instance variables as an attribute name, followed by a colon and the type. 
C)  Private attributes are preceded by the keyword private in the UML. 
D)  The UML models operations by listing the operation name followed by a set of parentheses. A plus sign (+) in front of the operation name indicates that the operation is a public. 
A)  In the UML, each class is modeled in a class diagram as a rectangle with three compartments. The top one contains the class's name centered horizontally in boldface. The middle one contains the class's attributes, which correspond to instance variables in Java. The bottom one contains the class's operations, which correspond to methods and constructors in Java. 
B)  UML represents instance variables as an attribute name, followed by a colon and the type. 
C)  Private attributes are preceded by the keyword private in the UML. 
D)  The UML models operations by listing the operation name followed by a set of parentheses. A plus sign (+) in front of the operation name indicates that the operation is a public.

Question 5

Which of the following statements is false?

Accepted Answer

A)  Scanner method next reads characters until any white-space character is encountered, then returns the characters as a String. 
B)  To call a method of an object, follow the object name with a comma, the method name and a set of parentheses containing the method's arguments. 
C)  A class instance creation expression begins with keyword new and creates a new object. 
D)  A constructor is similar to a method but is called implicitly by the new operator to initialize an object's instance variables at the time the object is created. 
A)  Scanner method next reads characters until any white-space character is encountered, then returns the characters as a String. 
B)  To call a method of an object, follow the object name with a comma, the method name and a set of parentheses containing the method's arguments. 
C)  A class instance creation expression begins with keyword new and creates a new object. 
D)  A constructor is similar to a method but is called implicitly by the new operator to initialize an object's instance variables at the time the object is created.

Question 6

An import declaration is not required if you always refer to a class with its ________ name, which includes its package name and class name.

Accepted Answer

A)  compile-time 
B)  default package 
C)  paired 
D)  fully qualified name 
A)  compile-time 
B)  default package 
C)  paired 
D)  fully qualified name

Question 7

Which of the following statements is true?

Accepted Answer

A)  Each object (instance) of the class shares the class's instance variables. 
B)  Most instance-variable declarations are preceded with the keyword public, which is an access modifier. 
C)  Variables or methods declared with access modifier private are accessible only to methods of the class in which they're declared. 
D)  None of the above is true. 
A)  Each object (instance) of the class shares the class's instance variables. 
B)  Most instance-variable declarations are preceded with the keyword public, which is an access modifier. 
C)  Variables or methods declared with access modifier private are accessible only to methods of the class in which they're declared. 
D)  None of the above is true.

Question 8

Which of the following statements is true?

Accepted Answer

A)  Constructors can specify parameters and return types. 
B)  Constructors can specify parameters but not return types. 
C)  Constructors cannot specify parameters but can specify return types. 
D)  Constructors can specify neither parameters nor return types. 
A)  Constructors can specify parameters and return types. 
B)  Constructors can specify parameters but not return types. 
C)  Constructors cannot specify parameters but can specify return types. 
D)  Constructors can specify neither parameters nor return types.

Question 9

Which of the following statements is false?

Accepted Answer

A)  Variables declared in the body of a particular method are local variables and can be used only in that method. 
B)  A method's parameters are local variables of the method. 
C)  Every method's body is delimited by left and right braces ({ and }). 
D)  Keyword null indicates that a method will perform a task but will not return any information. 
A)  Variables declared in the body of a particular method are local variables and can be used only in that method. 
B)  A method's parameters are local variables of the method. 
C)  Every method's body is delimited by left and right braces ({ and }). 
D)  Keyword null indicates that a method will perform a task but will not return any information.

Question 10

Java requires a ________ call for every object that's created.

Accepted Answer

A)  constructor 
B)  destructor 
C)  parameterless 
D)  parameterized 
A)  constructor 
B)  destructor 
C)  parameterless 
D)  parameterized

Question 11

Which of the following statements is false?

Accepted Answer

A)  A reference to an object is required to invoke an object's methods. 
B)  A primitive-type variable does not refer to an object. 
C)  Reference-type instance variables are initialized by default to the value void. 
D)  A primitive-type variable cannot be used to invoke a method. 
A)  A reference to an object is required to invoke an object's methods. 
B)  A primitive-type variable does not refer to an object. 
C)  Reference-type instance variables are initialized by default to the value void. 
D)  A primitive-type variable cannot be used to invoke a method.

Question 12

Reference-type variables (called references) store ________ in memory.

Accepted Answer

A)  the value of an object 
B)  a copy of an object 
C)  the location of an object 
D)  the size of an object 
A)  the value of an object 
B)  a copy of an object 
C)  the location of an object 
D)  the size of an object

Question 13

Declaring instance variables ________ is known as data hiding or information hiding.

Accepted Answer

A)  secure 
B)  private 
C)  static 
D)  masked 
A)  secure 
B)  private 
C)  static 
D)  masked

Question 14

Floating-point literals are of type ________ by default.

Accepted Answer

A)  float 
B)  double 
C)  real 
D)  decimal 
A)  float 
B)  double 
C)  real 
D)  decimal

Question 15

Types in Java are divided into two categories. The primitive types are boolean, byte, char, short, int, long, float and double. All other types are ________ types.

Accepted Answer

A)  static 
B)  reference 
C)  declared 
D)  source 
A)  static 
B)  reference 
C)  declared 
D)  source

Question 16

Which of the following statements is false?

Accepted Answer

A)  A primitive-type variable can store exactly one value of its declared type at a time. 
B)  Primitive-type instance variables are initialized by default. 
C)  Variables of types byte, char, short, int, long, float and double are initialized to 0. 
D)  Variables of type boolean are initialized to true. 
A)  A primitive-type variable can store exactly one value of its declared type at a time. 
B)  Primitive-type instance variables are initialized by default. 
C)  Variables of types byte, char, short, int, long, float and double are initialized to 0. 
D)  Variables of type boolean are initialized to true.

Question 17

A class that creates an object of another class, then calls the object's methods, is called a(n) ________ class.

Accepted Answer

A)  object-oriented 
B)  inherited 
C)  caller 
D)  driver. 
A)  object-oriented 
B)  inherited 
C)  caller 
D)  driver.

Question 18

Which of the following statements is false?

Accepted Answer

A)  The method's return type specifies the type of data returned to a method's caller. 
B)  Empty parentheses following a method name indicate that the method does not require any parameters to perform its task. 
C)  When a method that specifies a return type other than void is called and completes its task, the method must return a result to its calling method 
D)  Classes often provide public methods to allow the class's clients to set or get private instance variables; the names of these methods must begin with set or get. 
A)  The method's return type specifies the type of data returned to a method's caller. 
B)  Empty parentheses following a method name indicate that the method does not require any parameters to perform its task. 
C)  When a method that specifies a return type other than void is called and completes its task, the method must return a result to its calling method 
D)  Classes often provide public methods to allow the class's clients to set or get private instance variables; the names of these methods must begin with set or get.

Question 19

Which of the following statements is false?

Accepted Answer

A)  If a class does not define constructors, the compiler provides a default constructor with no parameters. 
B)  If you declare a constructor for a class, the compiler will not create a default constructor for that class. 
C)  The UML models constructors in the third compartment of a class diagram. 
D)  To distinguish a constructor from a class's operations, the UML places the word "constructor" between double quotes before the constructor's name. 
A)  If a class does not define constructors, the compiler provides a default constructor with no parameters. 
B)  If you declare a constructor for a class, the compiler will not create a default constructor for that class. 
C)  The UML models constructors in the third compartment of a class diagram. 
D)  To distinguish a constructor from a class's operations, the UML places the word "constructor" between double quotes before the constructor's name.

Question 20

Which of the following statements is false?

Accepted Answer

A)  Most classes you'll use in Java programs must be imported explicitly. 
B)  There's a special relationship between classes that are compiled in the same directory. By default, such classes are considered to be in the same package-known as the default package. 
C)  Classes in the same package are implicitly imported into main. 
D)  An import declaration is not required when one class in a package uses another in the same package. 
A)  Most classes you'll use in Java programs must be imported explicitly. 
B)  There's a special relationship between classes that are compiled in the same directory. By default, such classes are considered to be in the same package-known as the default package. 
C)  Classes in the same package are implicitly imported into main. 
D)  An import declaration is not required when one class in a package uses another in the same package.

Exam 3: Introduction to Classes, Objects, Methods and Strings

You must call most methods other than ________ explicitly to tell them to perform their tasks.

Which of the following statements is false?

Which of the following statements is false?

Which of the following statements is false?

Which of the following statements is false?

An import declaration is not required if you always refer to a class with its ________ name, which includes its package name and class name.

Which of the following statements is true?

Which of the following statements is true?

Which of the following statements is false?

Java requires a ________ call for every object that's created.

Which of the following statements is false?

Reference-type variables (called references) store ________ in memory.

Declaring instance variables ________ is known as data hiding or information hiding.

Floating-point literals are of type ________ by default.

Types in Java are divided into two categories. The primitive types are boolean, byte, char, short, int, long, float and double. All other types are ________ types.

Which of the following statements is false?

A class that creates an object of another class, then calls the object's methods, is called a(n) ________ class.

Which of the following statements is false?

Which of the following statements is false?

Which of the following statements is false?

Introduction to Computers, the Internet and Java

Introduction to Java Applications; Inputoutput and Operators

Control Statements: Assignment, and Operators

Control Statements: Logical Operators

Methods: a Deeper Look

Arrays and Arraylists

Classes and Objects: a Deeper Look

Object-Oriented Programming: Inheritance

Object-Oriented Programming: Polymorphism and Interfaces

Exception Handling: a Deeper Look

Javafx Graphical User Interfaces

Javafx Gui

Strings, Characters and Regular Expressions

Files, Inputoutput Streams, Nio and Xml Serialization

Generic Collections

Lambdas and Streams

Recursion

Searching, Sorting and Big O

Generic Classes and Methods: a Deeper Look

Custom Generic Data Structures

Concurrency

Accessing Databases With Jdbc

Swing Gui Components

Graphics and Java 2d

Networking

Java Persistence Api Jpa

Javaserver Faces Web Apps

Javaserver Faces Web Apps

Swing Gui Components

Filters