How to reverse a string in Java

Java is one of the most widely used programming languages in the world and hence a lot of questions are asked in interview from Java.

In this article, you will learn simple but most commonly asked Java Interview Question- How to reverse a string.
You will learn three method to reverse a string.
/*
  There is an API for reversing a string in Java. StringBuffer and StringBuilder provides reverse()
  method to reverse a string.
*/
package programs;

public class ReverseString {

    public static void main(String[] args) {
        /*************************method 1- Manual Method********************/
        String str = "India";
        String revStr = "";

        //Convert String to char array
        char[] strArray = str.toCharArray();

        //find length of char array
        int len = strArray.length;

        //iterate over char array from last index to first index
        for (int i = len - 1; i >= 0; i--) {
            revStr = revStr + str.charAt(i);
        }
        System.out.println("Method 1 : Manually reversing a string");
         System.out.println(revStr);
       
         /*************************method 2 - Using StringBuffer********************/
        StringBuffer sbf=new StringBuffer(str);
        System.out.println("Method 2 : Reverse string using StringBuffer");
        System.out.println(sbf.reverse());
       
        /*************************method 3 - Using StringBuilder********************/
        StringBuilder sbl=new StringBuilder(str);
        System.out.println("Method 3 : Reverse string using StringBuilder");
        System.out.println(sbl.reverse());
    }

}

Output:

Method 1 : Manually reversing a string

aidnI

Method 2 : Reverse string using StringBuffer

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Method 3 : Reverse string using StringBuilder

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