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

53 Mentors

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

16,665 Students

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

105 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

A tremendous learning opportunity to explore the depth of your own knowledge

Exercism is fantastic in learning new languages but that is not the extent of it. If you are a "more experienced" programmer you may have encountered impostor syndrome: the idea you don't really know what you think you know. Exercism lets you solve problems and put them in the space of open feedback which is a tremendous learning opportunity to explore the depth of your own knowledge. Even if you have been programming in a language for awhile it is worth checking into Exercism to see where you stand with current implementation practices.

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 Fredrik Rubensson

Fredrik Rubensson https://github.com/froderik

So Java would be my main language with something like 15+ years of experience. I don't particularly like it but it is what I know best!
Avatar of Adarsh K Kumar

Adarsh K Kumar My Blog

I'm a Software Developer with exposure to Java/Spring, Devops, Linux, Databases. Currently exploring Distributed Systems and Erlang.
Avatar of Cameron MacDonald

Cameron MacDonald GitLab

Java was my second language and I wrote it professionally as well for a recommender system.
Avatar of Marcus Bergenlid

Marcus Bergenlid https://github.com/mbergenlid

I'm a software engineer working professionally in Java, I love to learn new languages and to improve my coding style. My side projects are usually focused around learning some new language or technology.
Avatar of Adrian Spanu

Adrian Spanu https://github.com/aspanu

I work as a software engineer full time. I've been working in Java codebases for a number of years now and I really like the flexibility and usefulness of Java. I'm happy to help new coders discover the awesomeness of Java. Yes, it does exist :).
Avatar of Rahmeen Habib

Rahmeen Habib https://github.com/Rahmeen14

I write C++ at the university, have 10 week professional experience with Java in an intern project and am an RGSoC scholar for a JavaScript Project
Fun. Challenging. Interesting

Community-sourced Java exercises

These are a few of the 105 exercises on the Java track. You can see all the exercises here.

Rotational Cipher
medium
cryptography
integers
strings
Minesweeper
medium
conditionals
games
integers
lists
matrices
strings
Bank Account
medium
concurrency
exception handling
integers
Space Age
easy
conditionals
floating point numbers
Proverb
medium
arrays
loops
strings
Resistor Color
easy
arrays
strings
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 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.
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 Anna Weber

Anna Weber

I used to be a health economist, and am now on my way to becoming a software engineer. Exercism's Java track got me started with open source.

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

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