Java Program: Calculate Average of Integers using Streams

Java Stream: Exercise-1 with Solution

Write a Java program to calculate the average of a list of integers using streams.

Sample Solution:

Java Code:

import java.util.Arrays;
import java.util.List;

public class Main {
  public static void main(String[] args) {
    List < Integer > nums = Arrays.asList(1, 3, 6, 8, 10, 18, 36);
    System.out.println("List of numbers: " + nums);

    // Calculate the average using streams
    double average = nums.stream()
      .mapToDouble(Integer::doubleValue)
      .average()
      .orElse(0.0);

    System.out.println("Average value of the said numbers: " + average);
  }
}

Sample Output:

List of numbers: [1, 3, 6, 8, 10, 18, 36]
Average value of the said numbers: 11.714285714285714 

Explanation:

In the above exercise, we have a list of integers (1, 3, 6, 8, 10, 18, 36). Using streams, we convert each integer to a double using the mapToDouble method and calculate the average through the average() method, and finally retrieve the average value using the orElse method in case the stream is empty. The average value is then printed to the console.

Flowchart:

Java Code Editor:

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