Question 1

Class Number is ________ of both Integer and Double.

Accepted Answer

A)  the subclass 
B)  composed 
C)  a descendent 
D)  the superclass 
A)  the subclass 
B)  composed 
C)  a descendent 
D)  the superclass D

Question 2

Which statement is false?

Accepted Answer

A)  When declaring a generic method, the type parameter section is placed before the return type of the method. 
B)  Each type parameter section contains only one type parameter. 
C)  A type parameter is an identifier that specifies a generic type name. 
D)  Type parameters can represent only reference types. 
A)  When declaring a generic method, the type parameter section is placed before the return type of the method. 
B)  Each type parameter section contains only one type parameter. 
C)  A type parameter is an identifier that specifies a generic type name. 
D)  Type parameters can represent only reference types. B

Question 3

Which of the following statements is false?

Accepted Answer

A)  Wildcard type arguments enable you to specify method parameters, return values, variables, and so on, that act as supertypes of parameterized types. 
B)  A wildcard-type argument is denoted by ?, which represents an "unknown type." 
C)  Because a wildcard is a type-parameter name, you can use it as a type name throughout a method's body. 
D)  If a wildcard is specified without an upper bound, then only the methods of type Object can be invoked on values of the wildcard type. 
A)  Wildcard type arguments enable you to specify method parameters, return values, variables, and so on, that act as supertypes of parameterized types. 
B)  A wildcard-type argument is denoted by ?, which represents an "unknown type." 
C)  Because a wildcard is a type-parameter name, you can use it as a type name throughout a method's body. 
D)  If a wildcard is specified without an upper bound, then only the methods of type Object can be invoked on values of the wildcard type. C

Question 4

When compiling a generic class, the __________ option should be used to view the unchecked warning message.

Accepted Answer

A)  -Xlint:unchecked. 
B)  -X:unchecked. 
C)  -warning:unchecked. 
D)  -unchecked. 
A)  -Xlint:unchecked. 
B)  -X:unchecked. 
C)  -warning:unchecked. 
D)  -unchecked.

Question 5

A wildcard type argument is denoted by a(n) __________.

Accepted Answer

A)  asterisk (*). 
B)  underscore (_). 
C)  question mark (?). 
D)  caret (^). 
A)  asterisk (*). 
B)  underscore (_). 
C)  question mark (?). 
D)  caret (^).

Question 6

One generic Stack class could be the basis for creating many Stack classes,g., Stack, Stack and Stack. These classes are known as __________.

Accepted Answer

A)  subclasses. 
B)  generic subclasses. 
C)  concrete classes. 
D)  parameterized classes. 
A)  subclasses. 
B)  generic subclasses. 
C)  concrete classes. 
D)  parameterized classes.

Question 7

__________ is the default upper bound of a type parameter.

Accepted Answer

A)  String. 
B)  Comparable. 
C)  Class. 
D)  Object. 
A)  String. 
B)  Comparable. 
C)  Class. 
D)  Object.

Question 8

All generic method declarations have a type parameter section delimited by __________.

Accepted Answer

A)  curly brackets ({ and }). 
B)  angle brackets (). 
C)  square brackets ([ and ] ). 
D)  parenthesis. 
A)  curly brackets ({ and }). 
B)  angle brackets (). 
C)  square brackets ([ and ] ). 
D)  parenthesis.

Question 9

Generics provide __________ that allows programmers to catch invalid types at compile time.

Accepted Answer

A)  compile-time type safety. 
B)  compile-time exception handling. 
C)  compile-time error checking. 
D)  run-time type safety. 
A)  compile-time type safety. 
B)  compile-time exception handling. 
C)  compile-time error checking. 
D)  run-time type safety.

Question 10

Which statement is false?

Accepted Answer

A)  A generic method may be overloaded. 
B)  A class can provide two or more generic methods that specify the same method name but different method parameters. 
C)  A generic method cannot be overloaded by non-generic methods. 
D)  When the compiler encounters a method call, it searches for the method declaration that most precisely matches the method name and the argument types specified in the call. 
A)  A generic method may be overloaded. 
B)  A class can provide two or more generic methods that specify the same method name but different method parameters. 
C)  A generic method cannot be overloaded by non-generic methods. 
D)  When the compiler encounters a method call, it searches for the method declaration that most precisely matches the method name and the argument types specified in the call.

Question 11

__________ enable programmers to specify, with a single method declaration, a set of related methods.

Accepted Answer

A)  Overloaded methods. 
B)  Overriden methods. 
C)  Generic methods. 
D)  Generics. 
A)  Overloaded methods. 
B)  Overriden methods. 
C)  Generic methods. 
D)  Generics.

Question 12

Which of the following statements is true?

Accepted Answer

A)  Overloaded methods are often used to perform similar operations on different types of data. 
B)  When the compiler encounters a method call, it attempts to locate a method declaration with a name and parameters that are compatible with the argument types in the method call. 
C)  Both a) and b) are true. 
D)  Neither a) nor b) is true. 
A)  Overloaded methods are often used to perform similar operations on different types of data. 
B)  When the compiler encounters a method call, it attempts to locate a method declaration with a name and parameters that are compatible with the argument types in the method call. 
C)  Both a) and b) are true. 
D)  Neither a) nor b) is true.

Question 13

When the compiler translates a generic method into Java bytecodes, it uses __________ to replace the type parameters with actual types.

Accepted Answer

A)  erasure. 
B)  compile-time type replacement. 
C)  compile-time type checking. 
D)  compile-time type safety. 
A)  erasure. 
B)  compile-time type replacement. 
C)  compile-time type checking. 
D)  compile-time type safety.

Exam 20: Generic Classes and Methods: a Deeper Look

Class Number is ________ of both Integer and Double.

Which statement is false?

Which of the following statements is false?

When compiling a generic class, the __________ option should be used to view the unchecked warning message.

A wildcard type argument is denoted by a(n) __________.

One generic Stack class could be the basis for creating many Stack classes,g., Stack<Double>, Stack<Integer> and Stack<Employee>. These classes are known as __________.

__________ is the default upper bound of a type parameter.

All generic method declarations have a type parameter section delimited by __________.

Generics provide __________ that allows programmers to catch invalid types at compile time.

Which statement is false?

__________ enable programmers to specify, with a single method declaration, a set of related methods.

Which of the following statements is true?

When the compiler translates a generic method into Java bytecodes, it uses __________ to replace the type parameters with actual types.

Introduction to Computers, the Internet and Java

Introduction to Java Applications; Inputoutput and Operators

Introduction to Classes, Objects, Methods and Strings

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

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