F Peek.md

Peek:

Peek is used to perform an action on each element of the stream without modifying it. It is mainly used for debugging or logging while the stream is being processed.

List<Integer> result = List.of(1, 2, 3, 4).stream()
        .peek(n -> System.out.println("Processing: " + n))
        .map(n -> n * 2)
        .toList();

System.out.println(result);

Output:

Processing: 1
Processing: 2
Processing: 3
Processing: 4
[2, 4, 6, 8]

---

← Previous: E Sorted

Next: G Limit →