What is the difference between peek() and sorted() methods in the context of collections or streams?

The peek() and sorted() methods in Java Stream API serve different purposes:

• peek() — intermediate method that allows performing an action on each element of the stream without modifying the stream itself. Usually used for debugging or logging.

• sorted() — intermediate method that sorts the stream's elements according to natural order or a comparator, returning a new sorted stream.

Example:

List<String> list = Arrays.asList("banana", "apple", "cherry");

list.stream()
    .peek(s -> System.out.println("Before sorting: " + s))
    .sorted()
    .peek(s -> System.out.println("After sorting: " + s))
    .collect(Collectors.toList());

In this example, peek() outputs elements before and after sorting, while sorted() changes the order.

Summary:

• peek() — for side effects without data modification.
• sorted() — for changing the order of stream elements.