How to reverse string in Java without built in library

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Reversing string in java is available via StringBuilder class, we can use stringBuilder.reverse(), then it magically reverses the string. But like an interview task for a Java developer job, sometimes the interviewer wants you to test your algorithm ability. So we have to do it manually, but don't worry it’s not that hard to reverse a string in Java.

The thing that you need to do to reverse the string is basically just split the string into arrays of characters, and then loop all those characters through the array, and combine all the array but from the back.

And This is simple java code not using Java built in library that you can just copy paste for reverse a string in Java.

And here’s the comparison if you want to use String builder, it’s much cleaner and if you want to do it in real life, it’s much better using this way.

Java is a magical language, it’s general purpose higher level language support for developing scalable, from personal to enterprise application, with lots of built in tools to support you develop your apps faster without boiler plate codes.

There’s so many Java libraries that you can use for solving any kind of real world application. You can use Java basically for an enterprise Web application that needs to handle complex business logic with millions of users with tons of available libraries in the Java community.


I am an experiences web developer, have a good problem-solving and deep understanding of software development principles. With comprehensive skill set in Java, PHP, Python, C and JavaScript. Able to do database thing like MySQL and Oracle. Along with expertise in frameworks like Spring, React, and Firebase. Have a solid understanding of software development methodologies, like Agile and Scrum. I applies best practices to ensure the development process is efficient and of the highest quality output.

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