2 Ways to check If String is Palindrome in Java? Recursion and Loop

A String is said to be Palindrome if it is equal to itself in reverse order. You can use this logic to check if String is Palindrome or not. There are two common ways to find if a given String is Palindrome or not in Java, first by using for loop, also known as iterative algorithm and second by using recursion, also known as recursive algorithm. The crux of this problem lies in how do you reverse String in Java? because once you have the String in reverse order, problem reduced to just comparing itself with the reversed String. If both are equal then given String is Palindrome otherwise it's not. Also whether your solution is iterative or recursive will also determine by implementing this logic. If you reverse String using for loop then it become an iterative solution and if you reverse String using recursion then it become a recursive solution. In general, recursive solution are short, readable and more intuitive but subject to StackOverFlowError and that's why not advised to be used in production system. You should always be using iterative solution in production, unless your programming language supports tail recursion optimization e.g. Scala which eliminates risk of StackOverFlowError by internally converting a recursive solution to an iterative one. If you are doing this exercise as part of your Interview preparation then I suggest you to take a look at Cracking the Coding Interview: 150 Programming Questions and Solutions, as title says it contains 150 good questions based upon different topics e.g. String, array, linked list, binary tree, networking etc. A good book for preparing both Java and C++ interview.

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