Streams – limit() and skip() operations

Stream limit() and skip() are intermediate operations in Java. The limit(n) method will limit the n numbers of elements to be processed in a stream. While the skip(n) method will skip the first n number from the stream.

Syntax of the limit() method

  Stream<T> limit(long maxSize)

Stream<T> limit(long maxSize) limits a stream of T objects to a maximum size of maxSize. It returns a new Stream that contains only the first maxSize number of elements from the original stream.

Syntax of the skip() method

  Stream<T> skip(long n)

The skip() method returns a stream consisting of the remaining elements after discarding the first n elements. If this stream contains fewer than n elements, we’ll get an empty stream.

Java Stream limit() and skip() operations – examples

Example 1

A program that takes a stream of integers and uses the limit() method to limit the list to the first 5 elements and apply the map() function to each element, which multiplies it by 2. The result is then collected in a new List:

class Test {

  public static void main(String[] args) {
    List<Integer> numbers = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));

    List<Integer> resultList = numbers.stream()
            .limit(5)
            .map(num -> num * 2)
            .collect(Collectors.toList());

    System.out.println(resultList);
  }
}

Output: [2, 4, 6, 8, 10]

Example 2

A program that takes a stream of integers and multiplies elements by 2 but skips the first 5 elements, using the skip() method:

class Test {

  public static void main(String[] args) {
    List<Integer> numbers = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));

    List<Integer> resultList = numbers.stream()
            .skip(5)
            .map(num -> num * 2)
            .collect(Collectors.toList());

    System.out.println(resultList);
  }
}

Output: [12, 14, 16, 18, 20]

I hope this tutorial was helpful to you. To learn more, check out other Java Functional Programming tutorials.

 

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