Palindrome Number Example in Java

Introduction

Palindrome Number is a classic Java console program that demonstrates the concept with complete source code and sample output. Calculation programs apply formulas to solve geometry, statistics and numeric problems.

This tutorial walks through the program line by line, explains how the logic works, and highlights best practices you can apply in your own code.

Definition

A palindromic number or numeral palindrome is a number that remains the same when its digits are reversed. Like 16461, for example, it is “symmetrical”. Although palindromic numbers are most often considered in the decimal system, the concept of palindromicity can be applied to the natural numbers in any numeral system.

Palindrome Number Example Program

import java.util.Scanner;

class PalindromeNumber{ 
    public static void main(String args[]){ 
		System.out.print("Enter the Number: ");
		Scanner in= new Scanner(System.in);
		int num =in.nextInt();
		int n = num;
		int rev=0,rmd; 
		while(num > 0) { 
			rmd = num % 10; 
			rev = rev * 10 + rmd; 
			num = num / 10; 
		} 
		if(rev == n){
			System.out.println("The given number is a palindrome!");
		}
		else {
			System.out.println("The given number is not a palindrome"); 
		}
    } 
}

Sample Output

Enter the Number: 34543
The given number is a palindrome!

When to use

Use these formulas in homework tools, engineering calculators or anywhere repeated numeric computation is needed.

How it works

1. Execution begins in the main method — the JVM calls this method when you run the class.

2. import java.util.Scanner; imports a class used later in the program.

3. A println / print call writes text to the console — part of the sample output below.

4. A Scanner reads typed input from the keyboard (System.in).

5. int num =in.nextInt(); updates a variable used in the calculation or output.

6. int n = num; updates a variable used in the calculation or output.

7. int rev=0,rmd; updates a variable used in the calculation or output.

8. A loop repeats the block until its condition becomes false.

Best Practices

• Use meaningful variable and class names that describe their purpose.
• Compile and run the program locally — modify values to see how output changes.
• Read compiler errors carefully; they usually point to the exact line to fix.

Common Mistakes

• Copying code without understanding each line — practice by changing one statement at a time.
• Mismatching the public class name and the .java filename.
• Forgetting semicolons at the end of statements.