Question 1

A literal string is called a(n) ____.
A) anonymous object
B) String variable
C) empty string
D) wrapper

Accepted Answer

A literal string is considered an anonymous object because it is a direct instance of a string not assigned to a variable.

Question 2

Consider the statement: int anInt = Integer.parseInt("649");
You can tell that  parseInt() is a(n) ____ method because you use it with the class name and not with an  object.
A) programmer-defined
B) instance
C) static
D) immutable

Accepted Answer

Integer.parseInt() is a static method, which means it can be invoked using the class name (Integer) and does not require an instance of the class to be created.

Question 3

The ____ class contains standard methods for testing the values of characters.
A) char
B) character
C) StringChar
D) Character

Accepted Answer

The Character class contains standard methods for testing the values of characters, such as isDigit(), isLetter(), and isWhitespace(). The other options are either incorrect class names or not relevant to testing the values of characters.

Question 4

The ____ method returns the length of a String .
A) getSize()
B) getLength()
C) size()
D) length()

Accepted Answer

The correct method to return the length of a String in Java is length(). Therefore, option D is the correct choice. Options A, B, and C are not valid methods to get the length of a String in Java.

Question 5

A StringBuilder object contains a memory block called a _____, which might or might not contain a string.
A) capacity
B) buffer
C) reference
D) thread

Accepted Answer

A StringBuilder object contains a memory block called a buffer, which stores and manages the characters of the string. The capacity is the size of the buffer, and the reference is a variable that refers to the StringBuilder object's memory location. The thread is a separate path of execution within a program.

Question 6

To convert a String to an integer, you use the ____ class, which is part of java.lang and is automatically imported into programs you write.
A) StringBuilder
B) String
C) Integer
D) Convert

Accepted Answer

The Integer class provides the parseInt(String s) method that can be used to convert a String to an integer. This class is part of java.lang and is automatically imported, making it easy to use. Choice A (StringBuilder) is a class used for manipulating strings and does not provide a method for converting strings to integers. Choice B (String) is the class for representing a string of characters, but it does not provide a direct method for converting to an integer. Choice D (Convert) is not a class in Java standard library.

Question 7

The  String  class ____ method is similar to the  equals()  method. As its name implies, this method does not consider case when determining if two  String s are equivalent.
A) equalsCase()
B) equalsOmitCase()
C) equalsAllCase()
D) equalsIgnoreCase()

Accepted Answer

The answer of The  String  class ____ method is similar...

Question 8

The ____ method lets you add characters at a specific location within a StringBuilder object.
A) charAt()
B) insert()
C) append()
D) setCharAt()

Accepted Answer

The insert() method allows you to add characters at a specific location within a StringBuilder object. charAt() allows you to retrieve a specific character in the StringBuilder, append() adds characters to the end of the StringBuilder, and setCharAt() replaces a character at a specific location within the StringBuilder. Therefore, the best choice is insert().

Question 9

The ____ method takes a String argument and returns its double value.
A) parseString()
B) parseInt()
C) parseDouble()
D) returnDouble()

Accepted Answer

The parseDouble() method is the appropriate choice as it takes a String argument and returns a double value. The other options, parseString() is not a valid method and parseInt() returns an integer value instead of a double value. The option returnDouble() is not a valid method.

Question 10

String oneStr = "Welcome Jim" String twoStr = "Welcome Joe"
Given the lines of code above, which of the following regionMatches() expressions will result in a value of true ?
A) oneStr.regionMatches(8, twoStr, 8, 3)
B) oneStr.regionMatches(0, twoStr, 0, 7)
C) oneStr.regionMatches(8, twoStr, 0, 3)
D) oneStr.regionMatches(0, twoStr, 8, 3)

Accepted Answer

The method regionMatches() checks if the specified region of one string matches the specified region of another string. Option B compares the first 7 characters ("Welcome") of both strings, which are identical.

Question 11

To alter just one character in a StringBuilder , you can use the ____ method, which allows you to change a character at a specified position within a StringBuilder object.
A) charAt()
B) insert()
C) append()
D) setCharAt()

Accepted Answer

The setCharAt() method allows you to change a character at a specified position within a StringBuilder object. The charAt() method returns a character at a specified position, while the insert() and append() methods add characters to the StringBuilder.

Question 12

Which of the following correctly declares and initializes a String object?
A) new String = Hello
B) String greeting == "Hello";
C) String greeting = "Hello";
D) String new = "Hello"

Accepted Answer

Option C declares and initializes a String object with the value "Hello". Option A is incorrect because it does not specify the variable name. Option B uses the incorrect syntax for declaring a variable and initializing a String object. Option D uses a reserved word "new" as a variable name, which is not allowed.

Question 13

Assume that aName refers to Roger. What is returned by aName.compareTo("Robert"); 
A) 0
B) positive number
C) negative number
D) false

Accepted Answer

"Roger" comes after "Robert" alphabetically, so a positive number will be returned.

Question 14

The ____ method allows you to replace all occurrences of some character within a String .
A) substring()
B) toString()
C) replaceCharacter()
D) replace()

Accepted Answer

The replace() method allows you to replace all occurrences of some character within a String. The substring() method returns a substring of a given String, the toString() method returns a string representation of an object, and there is no built-in replaceCharacter() method in Java.

Question 15

The ____ method requires an integer argument that indicates the position of the character at that position, starting at 0.
A) charAt()
B) setCharAt()
C) strAt()
D) posChar()

Accepted Answer

The charAt() method is the only one among the options given that requires an integer argument that indicates the position of the character at that position, starting at 0. The other options are not valid Java string methods.

Question 16

The creators of Java chose ____ characters as the "extra" length for a StringBuilder object.
A) 12
B) 16
C) 36
D) 48

Accepted Answer

The creators of Java chose 16 characters as the "extra" length for a StringBuilder object. This is because it provides a good balance between not wasting too much memory on unused capacity and not constantly having to resize the buffer for small additions.

Question 17

The ____ method and the  startsWith()  method each take a  String  argument and return  true  or  false  if a  String  object does or does not end or start with the specified argument, respectively.
A) beginsWith()
B) strEnd()
C) endsWith()
D) length()

Accepted Answer

The answer of The ____ method and the  startsWith()  method...

Question 18

System.out.println("Your name is " + yourName); The above statement is an example of ____, which is used to join String s.
A) concatenation
B) referencing
C) parsing
D) buffering

Accepted Answer

This statement is an example of concatenation, which means joining two or more String values together to create a new String value. In this case, the String "Your name is " is joined with the value of the variable yourName to create a complete sentence.

Question 19

When the String class ____ method is used to compare two String s, it provides additional information to the user in the form of an integer value.
A) toString()
B) compareTo()
C) equals()
D) equalsIgnoreCase()

Accepted Answer

The compareTo() method is used to compare two strings and returns an integer value as an output. This integer value is 0 if both strings are equal, a negative value if the first string is lexicographically less than the second string, and a positive value if the first string is lexicographically greater than the second string. This additional information can be useful in sorting and searching operations. The other methods (toString(), equals(), and equalsIgnoreCase()) do not provide this additional integer value.

Question 20

The ____ method converts any object to a String .
A) convertString()
B) toString()
C) replace()
D) substring()

Accepted Answer

The toString() method is a built-in method in Java that returns a string representation of the object it is called on. It is the most appropriate method to convert any object to a String.

Quiz 7: Characters, Strings and the Stringbuilder

A literal string is called a(n) ____.

Consider the statement: int anInt = Integer.parseInt("649") ; You can tell that parseInt() is a(n) ____ method because you use it with the class name and not with an object.

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

The ____ method returns the length of a String .

A StringBuilder object contains a memory block called a _____, which might or might not contain a string.

To convert a String to an integer, you use the ____ class, which is part of java.lang and is automatically imported into programs you write.

The String class ____ method is similar to the equals() method. As its name implies, this method does not consider case when determining if two String s are equivalent.

The ____ method lets you add characters at a specific location within a StringBuilder object.

The ____ method takes a String argument and returns its double value.

String oneStr = "Welcome Jim" String twoStr = "Welcome Joe" Given the lines of code above, which of the following regionMatches() expressions will result in a value of true ?

To alter just one character in a StringBuilder , you can use the ____ method, which allows you to change a character at a specified position within a StringBuilder object.

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

Assume that aName refers to Roger. What is returned by aName.compareTo("Robert") ;

The ____ method allows you to replace all occurrences of some character within a String .

The ____ method requires an integer argument that indicates the position of the character at that position, starting at 0.

The creators of Java chose ____ characters as the "extra" length for a StringBuilder object.

The ____ method and the startsWith() method each take a String argument and return true or false if a String object does or does not end or start with the specified argument, respectively.

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

When the String class ____ method is used to compare two String s, it provides additional information to the user in the form of an integer value.

The ____ method converts any object to a String .