StringBuilder vs StringBuffer: Which is Right for String Operations?

Both statements are correct.

'Statement A: StringBuilder and StringBuffer should be used when various string operations need to be performed.' is true because both classes provide efficient methods for modifying strings without creating new objects for each change. This makes them ideal for tasks like appending, inserting, or deleting text within a string.

'Statement B: StringBuffer has the same methods as StringBuilder, however, the methods in the StringBuffer class are synchronized.' is also accurate. StringBuffer methods are synchronized, making them thread-safe. This means multiple threads can access and modify a StringBuffer object concurrently without causing data corruption. StringBuilder, on the other hand, is not synchronized, offering better performance in single-threaded environments.

In summary, choose StringBuilder for performance-critical applications where thread safety is not a concern. When thread safety is paramount, opt for StringBuffer.