What is the limit() method of Stream Interface?

When we call limit(N), we will get a new Stream with the first N elements of this Stream in the encounter orderThe order in which the elements of the stream are supplied..

For example, consider that we have a stream of ten elements and we called limit(5) on the stream. Then, a new stream with the first five elements of the original stream will be returned.

Syntax

Stream<T> limit(long N)

  • N: The number of elements the stream should be limited to.

  • The limit(N) method will return the first N elements in the encounter order of the Stream.

  • The limit(N) is a cheap operation on sequential stream pipelines.

  • In the ordered parallel stream, the limit method may be expensive if the value of N is large because the stream is processed in a parallel manner by different threads. This performance issue can be avoided by using the unordered stream, removing the ordering constraint with BaseStream.unordered(), or using a sequential stream instead of a parallel stream.

  • IllegalArgumentException is thrown if we pass negative numbers as the value for N.

Example

import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
 
class LimitExample {
    public static void main(String[] args) 
    {
        Stream<Integer> numbers = Stream.of(1, 2, 3, 4, 5);
         
        List<Integer> newList = numbers
                                        .limit(3)
                                        .collect(Collectors.toList());
        System.out.println(newList);
    }
}

In the above code:

  • We created a Stream of numbers with the name numbers, with the values:
1,2,3,4,5

  • We called the limit(3) method on the numbers stream. The limit(3) will return a new stream with the first three elements from the original stream.

  • Using the collect (Collectors.toList()) method, we were able to collect the stream as a List.

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