Java program to check whether string is palindrome

Let’s learn java program to check whether string is palindrome.

Java program to check whether string is palindrome

Check whether string is palindrome is one of the interview question. Palindrome string is a string where string remains same when reversed or a word spelled same way forwards and backwards.

Example: level, dad, mom, madam, abcba, etc.,

In the below program to check whether string is palindrome first user enters a string as input using nextLine() method of Scanner class. This string is stored in String variable ‘strInput’.

Then input string is reversed using for loop. Then using if else user entered string and reversed string checked for string palindrome using equalsIgnoreCase() method.

Here equalsIgnoreCase() method is used which compares this string to another string, ignoring case considerations. Here’s the syntax for equalsIgnoreCase() method.

public boolean equalsIgnoreCase(String anotherString)

equalsIgnoreCase() method returns true if the argument is not null and it represents an equivalent String ignoring case; false otherwise. Now let’s see java program.

import java.util.*;
public class PalindromeStringInJava
{
   public static void main(String[] args) 
   { 
      String strInput, strReverse = "";
      Scanner sc = new Scanner(System.in);
      System.out.print("Please enter the string : ");
      strInput = sc.nextLine();
      int num = strInput.length();
      for(int a = num - 1; a >= 0; a--)
      {
          strReverse = strReverse + strInput.charAt(a);
      }
      if(strInput.equalsIgnoreCase(strReverse))
      {
         System.out.println("String is palindrome.");
      }
      else
      {
         System.out.println("String is not palindrome.");
      }
      sc.close();
   }
}

Output:

java program to check whether string is palindrome