Java

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Java is a very widely used Object Oriented programming language. It's safe, simple to use and portable so that you can "write once, run anywhere".
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Track mentors

52 Mentors

Our mentors are friendly, experienced Java developers who will help teach you new techniques and tricks.
Track students

15,678 Students

Join thousands of students who have enjoyed learning and improving their skills by taking this track.
Track exercises

104 Exercises

Hundreds of hours have gone into making these exercises fun, useful, and challenging to help you enjoy learning.

About Java

class Greeter {

    String getGreeting() {
        return "Hello, World!";
    }

}

Java is among the most popular available programming languages, thanks to its versatility and compatibility. It is widely used for software development, mobile applications and developing larger systems.

Java was born in 1995 and is maintained by Oracle. Despite the fact that it isn't as young as some of the fresh languages out there, Java is still really popular. It was designed to be fast, secure, reliable, beginner-friendly and highly portable. This portability perk exists because Java is executed on a cross-platform compatible Java Virtual Machine - JVM. Android apps are also developed using Java, since the Android Operating System runs on a Java language environment.

The Java community is huge! GitHub for example has over 1.5 million Java projects. It's also worth mentioning that Java has the second largest community in StackOverflow! This is important because the larger a programming language community is, the more support you'd be likely to get.

Java also has a powerful and well-designed set of built-in APIs - Application Programming Interfaces, which can be used for various activities like Database connection, networking, I/O, XML parsing, utilities, and much more.

From laptops to datacenters, game consoles to scientific supercomputers, cell phones to the Internet, Java is everywhere!

Join the Java track

Exercism is a great website

The reviews are incredibly helpful because they help me see things that I missed, learn about new ways and sometimes interesting discussions that can add a fun twist to maybe a simple problem.

Relaxed. Encouraging. Supportive.

Meet the Java Track mentors

Once you join the Java language track, you will receive support and feedback from our team of mentors. Here are the bios of a few of the mentors of this track.

Avatar of Warren Wright

Warren Wright https://github.com/wrightling

I am a software engineer by training, build and run software teams in practice, and am a longtime fan and user of Exercism!
Avatar of Jônatas Barbosa

Jônatas Barbosa https://github.com/jonatascb

Java is one of my favorite languages. It's very powerful and versatile. Besides, you can build once and run everywhere! :)
Avatar of Robin Victorino

Robin Victorino https://github.com/rvictorino

I've been working as a Java developer for a bit more than 5 years now. Finding elegant solutions is something I value. I'm an open source enthusiast.
Avatar of James George

James George https://github.com/jamesgeorge007

I have experience with the Java Android framework as well as the traditional swing library for building Desktop apps.
Avatar of Crane Yuan

Crane Yuan Personal Blog Site

I am a backend developer. I've written code in Java professionally, as well as use it for open source contribution.
Avatar of Patrick Trottier

Patrick Trottier https://github.com/PTrottier

I am studying Computer Science in Canada. My passion for the Web as a platform for everyone and Open Source Software fuel my work on projects like Exercism.
Fun. Challenging. Interesting

Community-sourced Java exercises

These are a few of the 104 exercises on the Java track. You can see all the exercises here.

Triangle
medium
booleans
classes
exception handling
Resistor Color
easy
arrays
strings
Tournament
medium
loops
maps
parsing
sorting
text formatting
Rotational Cipher
medium
cryptography
integers
strings
Crypto Square
medium
cryptography
lists
security
strings
text formatting
Error Handling
medium
exception handling
optional values
Passionate. Knowledgeable. Creative.

Meet the Java Track maintainers

The Java Maintainers are the brains behind the Java Track. They spend their spare time creating interesting and challenging exercises that we can all learn from. We are incredibly grateful for their hard work. Here are the bios of a few of the maintainers of this track.

Avatar of Sam Warner

Sam Warner

I am a software developer and consultant working for Black Pepper Software, a software company based in Leamington Spa, England. I'm a recent Computer Science graduate from the University of Warwick, and love all things to do with computers!
Avatar of Frida Johanne Tveit

Frida Johanne Tveit

I'm a software developer working for Softwire, a UK based software company. I'm a full stack developer working with many different languages including Java. I love programming and helping other people learn more about it!
Avatar of Logan Stucki

Logan Stucki Sometimes I blog on my site

I'm a 17 year old student and code artisian. I love writing code and making things. Currently, I enjoy answering stackoverflow questions and making webapps when not contributing to exercism.

Get started with the Java track. As with everything on Exercism, it's 100% free!

Join the Java Track