Nth highest salary from a given list using Java 8 Streams or second highest salary

 

Nth highest salary from a given list using Java 8 Streams. Below is a step-by-step program that demonstrates this using distinct sorting and skipping elements.

Java Program: Find the Nth Highest Salary

import java.util.Arrays;

import java.util.List;

import java.util.Optional;

public class NthHighestSalary {

    public static void main(String[] args) {

        List<Integer> salaries = Arrays.asList(50000, 60000, 75000, 40000, 75000, 90000, 60000);

        int n = 4; // Change this value to find the nth highest salary

        Optional<Integer> nthHighest = salaries.stream()

                .distinct() // Remove duplicate salaries

                .sorted((a, b) -> Integer.compare(b, a)) // Sort salaries in descending order

                .skip(n - 1) // Skip (n-1) highest salaries

                .findFirst(); // Get the nth highest salary

        System.out.println(n + "th highest salary: " + nthHighest.orElse(null));

    }

}

Exaplnation 

Create a list of salaries: Some salaries may be duplicate.

Use .stream(): Convert the list into a stream.

Remove duplicates: .distinct() ensures only unique salaries are considered.

Sort in descending order: .sorted((a, b) -> Integer.compare(b, a)) arranges salaries from highest to lowest.

Skip (n-1) highest salaries: .skip(n - 1) moves past the first (n-1) elements.

Get the next element: .findFirst() extracts the Nth highest salary.

Print the result: If the salary exists, it prints, otherwise null is returned

Second highest salary with given list

import java.util.Arrays;

import java.util.List;

import java.util.Optional;

public class SecondHighestNumber {

    public static void main(String[] args) {

        List<Integer> numbers = Arrays.asList(12, 5, 8, 20, 15, 9, 20);

        Optional<Integer> secondHighest = numbers.stream()

                .distinct() // Remove duplicate numbers

                .sorted((a, b) -> Integer.compare(b, a)) // Sort in descending order

                .skip(1) // Skip the highest number

                .findFirst(); // Get the second highest

        System.out.println("Second highest number: " + secondHighest.orElse(null));

    }

}

2 ) 

import java.util.Arrays;

import java.util.List;

import java.util.Optional;

public class SecondHighestNumber {

    public static void main(String[] args) {

        List<Integer> numbers = Arrays.asList(12, 5, 8, 20, 15, 9, 20);

        Optional<Integer> highest = numbers.stream().max(Integer::compare);

        Optional<Integer> secondHighest = numbers.stream()

                .filter(num -> !num.equals(highest.orElse(null))) // Remove the highest

                .max(Integer::compare); // Find the second highest

        System.out.println("Second highest number: " + secondHighest.orElse(null));

    }

}

3 .

public class SecondHighestSalaryWithSet {

    public static void main(String[] args) {

        List<Employee> employees = Arrays.asList(

            new Employee("Alice", 50000),

            new Employee("Bob", 60000),

            new Employee("Charlie", 70000),

            new Employee("David", 80000),

            new Employee("Eve", 90000),

            new Employee("Frank", 90000) // Duplicate salary

        );

        // Find the second highest salary using a Set to eliminate duplicates

        Optional<Double> secondHighestSalary = employees.stream()

            .map(emp -> emp.salary)

            .collect(Collectors.toSet())               // Collect to a Set to remove duplicates

            .stream()

            .sorted(Comparator.reverseOrder())

            .skip(1)

            .findFirst();

        // Print the result

        System.out.println("Second Highest Salary: " + secondHighestSalary.orElse(-1));

    }

}