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

57 Mentors

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

18,666 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 Louie van Bommel

Louie van Bommel http://alwayswantedtoplay.com

I've been doing java for a long time, including a word game that was online for years. I love Haskell, and I'm learning Elm, Rust, and (yikes!) Perl. Say hi if ya like :)
Avatar of Quincy Bowers

Quincy Bowers https://github.com/quincy

I've been programming in Java professionally for six years, and in general for more than 15 years. I like to focus on clean legible code, because code that is easier to read is easier to understand.
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 Maykell Sánchez Romero

Maykell Sánchez Romero kellsaro

I enjoy learning and teaching programming languages. Web development enthusiast.
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 Carsten Dreesbach

Carsten Dreesbach https://github.com/HerbCSO

I've been using Java in my job for about 15 years now, but only became a full-time engineer about a year and a half ago (was in professional services doing customizations before that).
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.

Forth
hard
exception handling
lists
logic
parsing
stacks
strings
Sublist
medium
generics
lists
loops
searching
enumerations
Bank Account
medium
concurrency
exception handling
integers
Triangle
medium
booleans
classes
exception handling
OCR Numbers
hard
exception handling
lists
loops
parsing
strings
Poker
medium
games
parsing
sorting
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 Jason Runkle

Jason Runkle

I have been writing Java code professionally for the past 3 years and I have had a wonderful experience with it. The functional style of Java 8 took some getting used to, but it really improved my team's codebase and productivity.
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.
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!

Join the Java Track