Chapter 6 Exam

Which of the following statements about ASCII and Unicode are true?

• ASCII is a newer version of Unicode

• ASCII is used to represent characters in many languages, while Unicode can only describe a single language

• Strings formed from Unicode characters will always take less memory than strings formed from ASCII characters

• ASCII uses a single byte to represent 128 English characters, while Unicode uses multiples bytes to represent thousands of characters in many languages

Which of the following conditions would make it impossible for two strings to be considered equal by the String equals() method?

• The two strings have the same number of characters, and match exactly, except the capitalization is different.

• All of these are true

• The two strings have a different number of characters

• The two strings have the same number of characters but the contents are different

Which of the following expressions (1, 2, 3, 4) will produce a true result when the input and password string variables contain exactly the same characters?

1. input.equals(password)

2. password.equals(input)

3. input == password

4. password == input

• All will produce true

• 1 and 2 only

• 1 and 3 only

• 3 and 4 only

A user logs in by entering a username and password. If you want to compare the username to a known string value, and don't want capitalization differences to matter, which String method should you use?

• equalsIgnoreCase()

• compareCase()

• compare()

• equals()

Which of the following expressions should be used to determine if the contents of myString1 are equal to the contents of myString2?

• myString1 = myString2

• myString2.equals(myString1)

• myString1 == myString2

• They all work equally well

A user logs in by entering a username and password. If you want to compare the password to a known string value, and must have an exact match (including capitalization) for a true result, how should you compare those strings?

• Use the == equality operator

• Use the String equals() method

• Use the String equalsIgnoreCase() method

• All of these will work

Given the following three string variables, which expression will return true?

String myString1 = "not so loud!";

String myString2 = "NOT SO LOUD!";

String myString3 = "No thanks";

• myString3.equalsIgnoreCase("NO THANKS")

• They all return true

• myString1.equalsIgnoreCase(myString2)

• myString2.equalsIgnoreCase(myString1)

Given the statement below, what are the minimum and maximum valid character index values in myString3?

String myString3 = "No thanks";

• 0 and 9

• 0 and 8

• 1 and 8

• 1 and 9

If you attempt to access a string character using an index value that is equal to the length of the string, what will happen?

• You will get the last character in the string

• You will get an empty character

• You will get the first character in the string

• You will see an IndexOutOfBoundsException that halts your program

Which of the following statements would you use to see if the string variable named "emailAddress" contains the string "@"?

• emailAddress.search("@")

• String.contains("@")

• emailAddress.contains("@")

• emailAddress.find("@")