Some examples of java

Fibonacci.java

public class Fibonacci {

    public void printSeries(int n) {
        int first = 0;
        int second = 1;

        for (int i = 0; i < n; i++) {
            System.out.print(first + " ");

            int next = first + second;
            first = second;
            second = next;
        }
    }

    public static void main(String[] args) {
        Fibonacci fibonacci = new Fibonacci();
        fibonacci.printSeries(10);
    }
}

Output:

0 1 1 2 3 5 8 13 21 34

Main.java

public class Main {

    public static void main(String[] args) {

        PrimeChecker checker = new PrimeChecker();

        int number = 17;

        if (checker.isPrime(number)) {
            System.out.println(number + " is a Prime Number.");
        } else {
            System.out.println(number + " is not a Prime Number.");
        }
    }
}

class PrimeChecker {

    public boolean isPrime(int number) {

        if (number <= 1) {
            return false;
        }

        for (int i = 2; i < number; i++) {
            if (number % i == 0) {
                return false;
            }
        }

        return true;
    }
}

src/
│
├── app/
│   └── Main.java
│
└── utils/
    └── ArrayUtils.java

utils/ArrayUtils.java

package utils;

public class ArrayUtils {

    public int findLargest(int[] numbers) {

        int largest = numbers[0];

        for (int number : numbers) {
            if (number > largest) {
                largest = number;
            }
        }

        return largest;
    }
}

app/Main.java

package app;

import utils.ArrayUtils;

public class Main {

    public static void main(String[] args) {

        ArrayUtils arrayUtils = new ArrayUtils();

        int[] numbers = {12, 45, 7, 89, 23, 56};

        int largest = arrayUtils.findLargest(numbers);

        System.out.println("Largest Number: " + largest);
    }
}