Java Strings and Regular Expressions

What is string manipulation in Java?

• Converting strings to integers in Java.

• Creating new strings in Java.

• Sorting strings alphabetically in Java.

• Modifying or manipulating strings using methods and operations in Java.

How can regular expressions be used in Java?

• By importing the java.util.regex library

• By using the java.util.regex class

• By using the java.util.regex package

• By using the java.util.regex.Pattern class

What is the purpose of matching patterns with regular expressions?

• To search, extract, and manipulate text.

• To encrypt and decrypt text

• To generate random patterns

• To sort and filter data

How can patterns be replaced using regular expressions in Java?

• Using the replace() method of the String class

• Using the replace() method of the Pattern class

• Using the replaceAll() method of the String class

• Using the replaceFirst() method of the String class

What is the role of regular expressions in validating input?

• Regular expressions are used to generate random input data.

• Regular expressions are used to encrypt input data.

• Regular expressions are used to convert input data into different formats.

• Regular expressions are used to match and validate input data.

Which Java method is used for string concatenation?

• append

• concat

• join

• +

What is the difference between String and StringBuilder in Java?

• String is immutable while StringBuilder is mutable.

• String is mutable while StringBuilder is immutable.

• String and StringBuilder are the same thing.

• String and StringBuilder cannot be used interchangeably.

How can you check if a string contains a specific substring in Java?

• string.containsSubstring(substring)

• string.indexOf(substring) != -1

• string.contains(substring)

• substring.contains(string)

What is the syntax for defining a regular expression in Java?

• Pattern.compile(regex, flags)

• Pattern.compile(regex, Pattern.CASE_INSENSITIVE)

• Pattern.compile(regex)

• Pattern.compile(regex, Pattern.MULTILINE)

How can you split a string into an array of substrings using regular expressions in Java?

• You can split a string into an array of substrings using the substring() method from the String class in Java.

• You can split a string into an array of substrings using the join() method from the String class in Java.

• You can split a string into an array of substrings using the replace() method from the String class in Java.

• You can split a string into an array of substrings using the split() method from the String class in Java.