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

76 Mentors

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

39,730 Students

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

113 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!

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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 Frederic Meyer

Frederic Meyer https://github.com/corebreaker

French developper for more than 20 years in Management Systems, i was insterested in several languages and technologies like C++, Java, PHP, etc. Nowaday, i'm more intested in other language, but i use PHP sometimes, so i can help.
Avatar of Paul Aly

Paul Aly https://github.com/maly7

I've been developing in Java Professionaly for 5 years now. I'm passionate about writing clean code and learning new programming languages.
Avatar of Daniel Krauskopf

Daniel Krauskopf https://github.com/danruff5

I graduated from Fanshawe College with two programming degrees. I am currently a full-time employee for a large company using Java and many other technologies.
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 Paul Moore

Paul Moore https://github.com/pdmoore

I've been programming in Java and JUnit for almost as long as they've existed. I really appreciate the ability to effortlessly refactor code using these tools.
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.
Fun. Challenging. Interesting

Community-sourced Java exercises

These are a few of the 113 exercises on the Java track. You can see all the exercises here.

Sum Of Multiples
medium
arrays
conditionals
integers
loops
math
Word Count
medium
conditionals
integers
loops
maps
strings
Hangman
hard
strings
reactive programming
functional programming
Collatz Conjecture
medium
conditionals
exception handling
integers
recursion
math
Zebra Puzzle
medium
logic
Armstrong Numbers
easy
integers
math
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!

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