StringBuilder vs StringBuffer: Which Is Right for You?

Both statements are correct.

Statement A: 'StringBuilder' and 'StringBuffer' should be used when various string operations need to be performed. This is because both classes provide efficient methods for manipulating strings without creating new objects for each operation, unlike the immutable 'String' class.

Statement B: 'StringBuffer' has the same methods as 'StringBuilder', however, the methods in the 'StringBuffer' class are synchronized. This means that 'StringBuffer' is thread-safe, making it suitable for scenarios where multiple threads might modify the same string object concurrently. 'StringBuilder', on the other hand, is not thread-safe, but it offers better performance in single-threaded environments.

In summary, if you need thread safety, use 'StringBuffer'. If performance is a priority in a single-threaded environment, use 'StringBuilder'.