Java DoubleStream skip() Method

The skip() method in Java, part of the java.util.stream.DoubleStream interface, is used to discard the first n elements of the stream. This method is useful when you need to bypass a certain number of elements in a stream and process only the remaining elements.

Table of Contents

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

Introduction

The skip() method returns a new DoubleStream 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:

DoubleStream skip(long n)

Parameters:

• n: The number of leading elements to skip.

Returns:

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

Throws:

• IllegalArgumentException: If n is negative.

Understanding skip()

The skip() method allows you to ignore the first n elements of a DoubleStream. This can be useful for scenarios such as pagination, where you want to process elements starting from a specific position in the stream.

Examples

Basic Usage

To demonstrate the basic usage of skip(), we will create a DoubleStream and skip the first two elements.

Example

import java.util.stream.DoubleStream;

public class SkipExample {
    public static void main(String[] args) {
        DoubleStream doubleStream = DoubleStream.of(1.1, 2.2, 3.3, 4.4, 5.5);

        // Skip the first 2 elements
        DoubleStream skippedStream = doubleStream.skip(2);

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

Output:

3.3
4.4
5.5

Using skip() with Other Stream Operations

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

Example

import java.util.stream.DoubleStream;

public class SkipWithOtherOperationsExample {
    public static void main(String[] args) {
        DoubleStream doubleStream = DoubleStream.of(1.0, 2.0, 3.0, 4.0, 5.0);

        // Skip the first 2 elements, then filter and map the remaining elements
        DoubleStream processedStream = doubleStream.skip(2)
                                                   .filter(n -> n > 3.0)
                                                   .map(n -> n * 2);

        // Print the processed elements
        processedStream.forEach(System.out::println);
    }
}

Output:

8.0
10.0

Real-World Use Case

Skipping Initial Sensor Readings

In real-world applications, the skip() method can be used to ignore initial sensor readings that might be unreliable or need to be discarded.

Example

import java.util.stream.DoubleStream;

public class SensorDataSkipExample {
    public static void main(String[] args) {
        DoubleStream sensorData = DoubleStream.of(25.3, 26.7, 24.8, 27.5, 30.1);

        // Skip the first 2 sensor readings
        DoubleStream reliableSensorData = sensorData.skip(2);

        // Process the remaining sensor readings
        reliableSensorData.forEach(reading -> System.out.println("Reliable reading: " + reading));
    }
}

Output:

Reliable reading: 24.8
Reliable reading: 27.5
Reliable reading: 30.1

Conclusion

The DoubleStream.skip() method is used to discard the first n elements of the stream. This method is particularly useful for scenarios where you need to process elements starting from a specific position in the stream. By understanding and using this method, you can efficiently manage and manipulate streams of double values in your Java applications.