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

43,419 Students

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

114 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 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 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 Abdul Wahab

Abdul Wahab https://github.com/arwahab

Software developer versed in Java & Spring Boot looking to teach others and also learn from them
Avatar of Nordwin Hoff

Nordwin Hoff Twitter

I am developper working with java and javascript every day. I love to learn new things and share it with people around me. I believe in team work, well designed code and simple things to make coding a fun experience.
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 Marcos Brizeno

Marcos Brizeno https://github.com/MarcosX

I like to keep learning about languages, tools and anything that make developing software fun!
Fun. Challenging. Interesting

Community-sourced Java exercises

These are a few of the 114 exercises on the Java track. You can see all the exercises here.

Anagram
medium
arrays
conditionals
equality
lists
loops
strings
Circular Buffer
hard
classes
exception handling
queues
Variable Length Quantity
medium
bitwise operations
conditionals
exception handling
lists
loops
transforming
Binary Search Tree
medium
generics
graphs
searching
sorting
trees
ISBN Verifier
medium
integers
loops
strings
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 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!

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

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