Master Java Stream skip() and limit(): When and How to Trim Your Data

1. Introduction

In Java 8 Stream API, the skip() and limit() methods are intermediate operations that trim a stream. This article explores their behavior and differences.

2. skip()

skip(long n)

skips the first n elements of a stream. Example implementation:

public static void skip(long n) {
    Stream<Integer> integerStream = Stream.of(1, 2, 3, 4, 5, 6);
    integerStream.skip(n).forEach(i -> System.out.println("integer = " + i));
}

If n < 0, an IllegalArgumentException is thrown. When n = 0, the stream is unchanged. If n equals or exceeds the stream size, the result is an empty stream (count = 0). Thus skip(long n) discards the first n (non‑negative) elements and may return an empty stream.

3. limit()

limit(long maxSize)

restricts a stream to at most maxSize elements. Example:

public static void limit(long maxSize) {
    Stream<Integer> integerStream = Stream.of(1, 2, 3, 4, 5, 6);
    integerStream.limit(maxSize).forEach(i -> System.out.println("integer = " + i));
}

If maxSize < 0, an IllegalArgumentException is thrown. When maxSize = 0, the result is an empty stream. For maxSize = 4, the first four elements (1‑4) are printed; for maxSize = 8, all elements are printed, similar to pagination in SQL.

4. Differences

Both methods truncate a stream, but skip is a stateful operation that depends on the current position of elements, while limit is a short‑circuit operation that stops once the specified maximum size is reached.

5. Conclusion

The article examined Java Stream API’s skip() and limit() methods and discussed scenarios where each is appropriate.