Java Interview Programs With Solutions

If you’re interviewing for a Java programming role, then your coding skills will probably be tested. Whether you’re a beginner in Java or an expert programmer, this article provides some common Java interview questions and answers to help you prepare.

1. How do you reverse a string in java ?

There is no reverse() utility method in the String class. However, you can create a character array from the string and then iterate it from the end to the start. You can StringBuilder class reverse() to return the reversed string.

public class ReverseString {
    public static void main(String[] args) {
        String str = "Hello";
        String reversed = new StringBuilder(str).reverse().toString();
        System.out.println(reversed);
    }
}

2. How do you check whether a string is a palindrome in Java?

A palindrome string is the same string backwards or forwards. To check for a palindrome, you can reverse the input string and check if the result is equal to the input.

public class PalindromeCheck {
    public static void main(String[] args) {
        String str = "madam";
        String reversed = new StringBuilder(str).reverse().toString();
        boolean isPalindrome = str.equals(reversed);
        System.out.println(isPalindrome);
    }
}

3. Write a Java program to print a Fibonacci sequence.

A Fibonacci sequence is one in which each number is the sum of the two previous numbers.

public class Fibonacci {
    public static void main(String[] args) {
        int n = 10, first = 0, second = 1;
        System.out.print("Fibonacci Series: ");
        for (int i = 1; i <= n; i++) {
            System.out.print(first + " ");
            int next = first + second;
            first = second;
            second = next;
        }
    }
}

4. How can you find the factorial of an integer in Java?

The factorial of an integer is calculated by multiplying all the numbers from 1 to the given number:

public class Factorial {
    public static void main(String[] args) {
        int num = 5;
        long factorial = 1;
        for (int i = 1; i <= num; i++) {
            factorial *= i;
        }…