Question 1

Strings that cannot be changed are said to be immutable. What does this mean and how does it relate to values held in memory addresses?

Accepted Answer

When you reference a String, you actually are accessing the address of the characters that make up the String. If you subsequently assign a new value to the String, the address held by the original String is altered . The String now holds a new address where the characters are stored. The original String is still in memory, but the String no longer holds its address. Eventually, a part of the Java system called the garbage collector discards the String characters. Strings, therefore, are never actually changed; instead, new Strings are created and String references hold the new addresses. Strings that can't be changed are called immutable.

Question 2

StringBuilder greeting = new StringBuilder("Day 1");
Using the above StringBuilder, create a setCharAt() method that will change the "1" to a "2" in the String "Day 1". Explain how the setCharAt() method operates.

Accepted Answer

greeting.setCharAt(4, '2');
To alter just one character in a StringBuilder, you can use the setCharAt() method, which allows you to change a character at a specified position within a StringBuilder object. This method requires two arguments: an integer position and a character. In the phrase "Day 1", the greeting.setCharAt(4, '2'); changes the value 1 to 2.

Question 3

Match each term with the correct statement below.
-Returns the lowercase equivalent of the argument

Accepted Answer

A) parseDouble() 
B) toLowerCase() 
C) substring() 
D) String variable 
E) append()
F)buffer
G)setLength()
H)indexOf()
I)insert() 
A) parseDouble() 
B) toLowerCase() 
C) substring() 
D) String variable 
E) append()
F)buffer
G)setLength()
H)indexOf()
I)insert() B

Question 4

System.out.println("Your name is " + yourName); The above statement is an example of ____, which is used to join Strings.

Accepted Answer

A)  concatenation 
B)  referencing 
C)  parsing 
D)  buffering 
A)  concatenation 
B)  referencing 
C)  parsing 
D)  buffering

Question 5

What is the purpose of the substring() method and how do you use it?

Accepted Answer

You can extract part of a String with th

Question 6

Match each term with the correct statement below.
-Add characters to the end of a StringBuilder object

Accepted Answer

A) parseDouble() 
B) toLowerCase() 
C) substring() 
D) String variable 
E) append()
F)buffer
G)setLength()
H)indexOf()
I)insert() 
A) parseDouble() 
B) toLowerCase() 
C) substring() 
D) String variable 
E) append()
F)buffer
G)setLength()
H)indexOf()
I)insert()

Question 7

String aName = "Michael"
Using the above statement, write the length() method that will return the length of the aName String. What value will the length() method return when executed?

Accepted Answer

int len = aName.leng

Question 8

In Java, to ____________________ a String means to break down its separate characters into a numeric format.

Accepted Answer

The answer of In Java, to ____________________ a String means...

Question 9

Strings and other objects that can't be changed are known as ____.

Accepted Answer

A)  string constants 
B)  accessor methods 
C)  immutable 
D)  garbage 
A)  string constants 
B)  accessor methods 
C)  immutable 
D)  garbage

Question 10

Which of the following correctly declares and initializes a String object?

Accepted Answer

A)  new String = Hello 
B)  String greeting == "Hello"; 
C)  String greeting = "Hello"; 
D)  String new = "Hello" 
A)  new String = Hello 
B)  String greeting == "Hello"; 
C)  String greeting = "Hello"; 
D)  String new = "Hello"

Question 11

A literal string is a(n) ____ object.

Accepted Answer

A)  lost 
B)  anonymous 
C)  class 
D)  named 
A)  lost 
B)  anonymous 
C)  class 
D)  named

Question 12

To convert a String to an integer, you use the valueOf() method of the ____ class.

Accepted Answer

A)  StringBuilder 
B)  String 
C)  Integer 
D)  Convert 
A)  StringBuilder 
B)  String 
C)  Integer 
D)  Convert

Question 13

When you compare Strings with the == operator, you are comparing their values, not their memory addresses.

Accepted Answer

A) True 
 B)False

Question 14

The StringBuilder class is more efficient than the StringBuffer class because it can execute multiple threads during program execution.

Accepted Answer

A) True 
 B)False

Question 15

You can tell that the equals() method takes a ____ argument because parentheses are used in the method call.

Accepted Answer

A)  String 
B)  Null 
C)  Double 
D)  Boolean 
A)  String 
B)  Null 
C)  Double 
D)  Boolean

Question 16

myCounty = " Clark Jackson Scioto"
myCounty.charAt(6)
Using the above code, what will be the value of the charAt() method once the code executes? Explain how the charAt() method operates.

Accepted Answer

The charAt() method requires an integer

Question 17

String greeting = "Welcome back";
Using the above statement, write the length() method that will return the length of the greeting String. Store the length in an integer named greetingLength.

Accepted Answer

int greeti

Question 18

What is a wrapper and why would you use it?

Accepted Answer

The Integer class is an example of a wra

Question 19

Describe how a programmer would use the two types of Character class methods (those that begin with "is" and those that begin with "to") for testing the values of characters.

Accepted Answer

The methods that begin with "is", such a

Question 20

The ____________________ class contains standard methods for testing the values of characters.

Accepted Answer

The answer of The ____________________ class contains standard methods for...

Strings that cannot be changed are said to be immutable. What does this mean and how does it relate to values held in memory addresses?

StringBuilder greeting = new StringBuilder("Day 1"); Using the above StringBuilder, create a setCharAt() method that will change the "1" to a "2" in the String "Day 1". Explain how the setCharAt() method operates.

Match each term with the correct statement below. -Returns the lowercase equivalent of the argument

System.out.println("Your name is " + yourName); The above statement is an example of ____, which is used to join Strings.

What is the purpose of the substring() method and how do you use it?

Match each term with the correct statement below. -Add characters to the end of a StringBuilder object

String aName = "Michael" Using the above statement, write the length() method that will return the length of the aName String. What value will the length() method return when executed?

In Java, to ____________________ a String means to break down its separate characters into a numeric format.

Strings and other objects that can't be changed are known as ____.

Which of the following correctly declares and initializes a String object?

A literal string is a(n) ____ object.

To convert a String to an integer, you use the valueOf() method of the ____ class.

When you compare Strings with the == operator, you are comparing their values, not their memory addresses.

The StringBuilder class is more efficient than the StringBuffer class because it can execute multiple threads during program execution.

You can tell that the equals() method takes a ____ argument because parentheses are used in the method call.

myCounty = " Clark Jackson Scioto" myCounty.charAt(6) Using the above code, what will be the value of the charAt() method once the code executes? Explain how the charAt() method operates.

String greeting = "Welcome back"; Using the above statement, write the length() method that will return the length of the greeting String. Store the length in an integer named greetingLength.

What is a wrapper and why would you use it?

Describe how a programmer would use the two types of Character class methods (those that begin with "is" and those that begin with "to") for testing the values of characters.

The ____________________ class contains standard methods for testing the values of characters.

Creating Java Programs

Using Data

Using Methods, Classes, and Objects

More Object Concepts

Making Decisions

Looping

Arrays

Advanced Array Concepts

Introduction to Inheritance

Advanced Inheritance Concepts

Exception Handling

File Input and Output

Introduction to Swing Components

Advanced Gui Topics

Graphics

Applets, Images, and Sound

Filters

Exam 7: Characters, Strings, and the Stringbuilder

Strings that cannot be changed are said to be immutable. What does this mean and how does it relate to values held in memory addresses?

StringBuilder greeting = new StringBuilder("Day 1"); Using the above StringBuilder, create a setCharAt() method that will change the "1" to a "2" in the String "Day 1". Explain how the setCharAt() method operates.

Match each term with the correct statement below. -Returns the lowercase equivalent of the argument

System.out.println("Your name is " + yourName); The above statement is an example of ____, which is used to join Strings.

What is the purpose of the substring() method and how do you use it?

Match each term with the correct statement below. -Add characters to the end of a StringBuilder object

String aName = "Michael" Using the above statement, write the length() method that will return the length of the aName String. What value will the length() method return when executed?

In Java, to ____________________ a String means to break down its separate characters into a numeric format.

Strings and other objects that can't be changed are known as ____.

Which of the following correctly declares and initializes a String object?

A literal string is a(n) ____ object.

To convert a String to an integer, you use the valueOf() method of the ____ class.

When you compare Strings with the == operator, you are comparing their values, not their memory addresses.

The StringBuilder class is more efficient than the StringBuffer class because it can execute multiple threads during program execution.

You can tell that the equals() method takes a ____ argument because parentheses are used in the method call.

myCounty = " Clark Jackson Scioto" myCounty.charAt(6) Using the above code, what will be the value of the charAt() method once the code executes? Explain how the charAt() method operates.

String greeting = "Welcome back"; Using the above statement, write the length() method that will return the length of the greeting String. Store the length in an integer named greetingLength.

What is a wrapper and why would you use it?

Describe how a programmer would use the two types of Character class methods (those that begin with "is" and those that begin with "to") for testing the values of characters.

The ____________________ class contains standard methods for testing the values of characters.

Creating Java Programs

Using Data

Using Methods, Classes, and Objects

More Object Concepts

Making Decisions

Looping

Arrays

Advanced Array Concepts

Introduction to Inheritance

Advanced Inheritance Concepts

Exception Handling

File Input and Output

Introduction to Swing Components

Advanced Gui Topics

Graphics

Applets, Images, and Sound

Filters