Java Stream skip() Method

The skip() method in Java, part of the java.util.stream.Stream interface, is used to skip the first n elements of the stream. This method is useful when you need to bypass a specific number of elements in the stream and continue processing the remaining elements.

Table of Contents

1. Introduction
2. skip() Method Syntax
3. Understanding skip()
4. Examples
   • Basic Usage
   • Using skip() in Combination with Other Stream Operations
5. Real-World Use Case
6. Conclusion

Introduction

The skip() method returns a stream consisting of the remaining elements of the original stream after discarding the first n elements. This method is an intermediate operation, meaning it returns a new stream and does not modify the original stream.

skip() Method Syntax

The syntax for the skip() method is as follows:

Stream<T> skip(long n)

Parameters:

• n: The number of leading elements to skip.

Returns:

• A new Stream consisting of the remaining elements of the original stream after discarding the first n elements.

Throws:

• This method does not throw any exceptions.

Understanding skip()

The skip() method allows you to discard the first n elements from a stream and continue processing the remaining elements. This is useful for scenarios where you need to ignore a certain number of elements and focus on the rest, such as pagination or removing headers from a dataset.

Examples

Basic Usage

To demonstrate the basic usage of skip(), we will create a Stream of integers and use skip() to skip the first 3 elements.

Example

import java.util.stream.Stream;

public class SkipExample {
    public static void main(String[] args) {
        Stream<Integer> stream = Stream.of(1, 2, 3, 4, 5, 6);

        // Use skip() to skip the first 3 elements
        Stream<Integer> skippedStream = stream.skip(3);

        // Print the remaining elements
        skippedStream.forEach(System.out::println);
    }
}

Output:

4
5
6

Using skip() in Combination with Other Stream Operations

This example shows how to use skip() in combination with other stream operations, such as filtering and limiting.

Example

import java.util.stream.Stream;

public class SkipWithFilterExample {
    public static void main(String[] args) {
        Stream<String> stream = Stream.of("apple", "banana", "cherry", "date", "elderberry", "fig", "grape");

        // Use skip() to skip the first 2 elements and filter to keep elements with length greater than 4
        Stream<String> filteredStream = stream.skip(2)
                                              .filter(s -> s.length() > 4);

        // Print the remaining elements
        filteredStream.forEach(System.out::println);
    }
}

Output:

cherry
elderberry
grape

Real-World Use Case

Implementing Pagination

In real-world applications, the skip() method can be used to implement pagination by skipping elements and limiting the number of elements processed.

Example

import java.util.stream.Stream;

public class PaginationExample {
    public static void main(String[] args) {
        Stream<String> stream = Stream.of("apple", "banana", "cherry", "date", "elderberry", "fig", "grape");

        int page = 2;
        int pageSize = 3;

        // Use skip() to skip elements of previous pages and limit to get the elements of the current page
        Stream<String> pageStream = stream.skip((page - 1) * pageSize)
                                          .limit(pageSize);

        // Print the elements of the current page
        pageStream.forEach(System.out::println);
    }
}

Output:

date
elderberry
fig

Conclusion

The Stream.skip() method is used to skip the first n elements of a stream and continue processing the remaining elements. This method is particularly useful for scenarios such as pagination or removing headers from a dataset. By understanding and using this method, you can efficiently manage and process streams of values in your Java applications, focusing on the elements that are relevant to your needs.