SCJP Java String Handling and Regular Expressions 3

Question 1

Which class from java.util.regex is used to perform match operations on input strings?

Accepted Answer

Matcher

Answer

Pattern

Answer

Regex

Answer

RegexEngine

Question 2

What is the output of: new StringBuilder("Hello").reverse().toString();

Accepted Answer

olleH

Answer

Hello

Answer

Compilation error

Answer

null

Question 3

What does the regular expression "^[A-Z]" match?

Accepted Answer

A string that starts with an uppercase letter

Answer

Any uppercase letter anywhere in the string

Answer

Any string containing only uppercase letters

Answer

The end of a string followed by an uppercase letter

Question 4

What is the difference between String.equals() and String.equalsIgnoreCase()?

Accepted Answer

equals() is case-sensitive; equalsIgnoreCase() ignores letter case differences

Answer

equals() compares references; equalsIgnoreCase() compares content

Answer

equals() works only with literals; equalsIgnoreCase() works with all Strings

Answer

There is no difference between the two methods

Question 5

What is the output of: String.format("%05d", 42);

Accepted Answer

"00042"

Answer

"42"

Answer

"42000"

Answer

"   42"

Question 6

Which StringBuilder method appends a String to the end of the buffer?

Accepted Answer

append()

Answer

add()

Answer

concat()

Answer

insert()

Question 7

What does the regex quantifier {2,5} mean?

Accepted Answer

Between 2 and 5 occurrences (inclusive)

Answer

Exactly 2 or exactly 5 occurrences

Answer

At least 5 but no more than 2 occurrences

Answer

Exactly 25 occurrences