Online Java Compiler

An online compiler is a cloud-based IDE that helps the developer to compile and execute a Java program online without installing the JDK in the local system. In this section, we will discuss some popular online Java compilers that are available free of cost.

The popular online Java compilers are:

1. JDoodle
2. GDB Online Compiler
3. Browxy
4. Repl
5. CodeInterview
6. Rextester
7. Ideone
8. Paiza
9. CODE PLAYGROUND

JDoodle

JDoodle is one of the fastest growing popular online Java compiler. The interface of JDoodle is very user friendly and easy to work with. Using the online compiler we can write, edit, run, save, share, and evaluate our code in realtime, in the browser. It also provides facility to save the code for future use.

It has all the standard Java libraries. We can use the libraries that are publicly available on Apache Maven, a build automation tool. Besides Java programming, JDoodle provides online IDE for other programming languages such as C, C++, Python, Ruby, Scala, Groovy, Rust, Go, Kotlin, etc.

Using JDoodle, we can generate an URL for the project code that can be shared among other programming buddies. Hence, pair programming and peer review can be easier.

JDoodle also provides a facility to create online courses and assignments. Its beta version is now available that is absolutely free and called as Guru Plan of JDoodle.

Follow the link to access the JDoodle online Java compiler: https://www.jdoodle.com/online-java-compiler/

When we access the above URL, it opens the following page with Java addition program as the default code. We can also execute our code with different versions of JDK.

GDB Online Compiler

GDB online compiler was released in 2016. It offers a lot of features. Just like JDoodle, GDB also supports variety of programming languages and provides many productive features.

One of the very helpful features of GDB compiler is built-in debugger. We can write a program, check for errors, set the breakpoints in order to debug the program and fix the errors. While debugging the code we can check the variable values at breakpoints and avoid the errors.

The other features such as code formatter to beautify the code automatically, the feature to download and save files, command-line arguments, etc.

Follow the link to access the GDB online Java compiler: https://www.onlinegdb.com/

When we access the above URL, it opens the following page:

Browxy

Browxy is one of the easy to use online Java compiler. It is available since many years. As it provides ready to use Java environment it is widely used by programmers.

Browxy provides three types of views mentioned as below:

1. Console view
2. Applet view
3. Log view for analysis and error reporting.

One has to sign in if they want to keep track of their code, upload snippets, save projects, run through snippets, and to submit snippets publicly to help others, etc.

It has ready to use programming examples that anyone can access and execute accordingly. The examples available are CSV writer, password generator, Loan calculator, animated gif creator, and many more.

Follow the link to access the Browxy online Java compiler: https://www.browxy.com/

When we access the above URL, it opens the following page:

Replit

Replit is very huge platform that supports more than 50 programming languages. During the past few years, Replit has become an extraordinary online Java development environment. Because of its different features we can not only say it as an online Java compiler.

The major advantage of Replit is that it is very lightweight but at the same time it carries all the features and helps us to write and execute the programs in an online environment.

Important aspects of using Replit online compiler is:

• We can import third party Jar files, libraries and Java frameworks
• Debugger for identifying the errors with ease.
• Hot module reloads for live updates.
• Cloud services are used for saving projects.
• Provides well explained examples.
• Terminal emulator loaded with features.
• Some advanced features include API integration that can be used to include compiler features in third party websites or apps.
• We can also import code from the GitHub.

The Replit online environment is also popular among educational institutes and mentors of many universities including Carnegie Mellon University, Trinket and Flatiron school to name a few.

Follow the link to access the Replit online Java compiler: https://replit.com/languages/java10

When we access the above URL, it opens the following page:

PaizaCloud

PaizaCloud is a new compiler. It is pretty much famous for its features. It is an advanced compiler and used for commercial purpose. It also has a free version.

PiazaCloud interface can be accessed in different languages such as Spanish, Japnese and English. Using the free version of PaizaCloud online compiler, the user is allowed to save the code, link the git account and also auto-sync the written code.

There are few options to customize the editor, set themes, change fonts, colors, etc. We can also have the facility for real-time collaboration using team mode.

It also offers a cloud version for web development, where development environments with different configurations are available to use.

Follow the link to access the PaizaCloud online Java compiler: https://paiza.io/en

When we access the above URL, it opens the following page:

CODE PLAYGROUND

CODE PLAYGROUND is a very popular IDE and learning environment. It provides a built-in online Java compiler. So that a viewer can directly access the code and play with it on the same website. It allows to write, compile and execute the code in the browser and displays the live output.

It doesn't offer many features like other websites but it does the basic job. New programmers get options to save the code, create projects, and download code, share, and much more. The main reason behind the online compiler is the user does not need to go to another website for executing the programs.

Follow the link to access the CODE PLAYGROUND application: https://www.codeplayground.app/

When we access the above URL, it opens the following page:

Ideone

Ideone also offers a very sophisticated Java compiler and uses its own proprietary Sphere engine. Using ideone, the programmer can monitor the time taken for code execution, memory utilization, compiler errors, runtime errors, etc. and much more.

Ideone allows the modify the user interface as per their requirements, download the source code, mark the project public for others to use their code snippets, mark the code private for their own viewing later on, and much more. It also has a syntax highlighting option in here.

The proprietary sphere engine used by Ideone is also available for other businesses for commercial use and is used majorly in hackathons and coding interviews etc.

Follow the link to access the Ideone online Java compiler: https://ideone.com/

When we access the above URL, it opens the following page:

Rextester

It is another popular online Java compiler, started off as a Regular Expression tester but is fast becoming a compiler of choice among the community of Java developers.

The code wall feature on Rextester allows you to see a running list of code snippets submitted by others.

Collaboration is another cool feature of Rextester, start the code, share the URL with your team, and start editing together.

Follow the link to access the Rextester online Java compiler: https://rextester.com/l/java_online_compiler

When we access the above URL, it opens the following page:

Cloud9

Cloud 9 is an enterprise-grade cloud development environment. It is not just an online java compiler, this is a full-featured collaboration tool for large teams and for large scale complex projects.

Cloud 9 is very popular among big organizations and is a leading commercial player in the market of online development tools. We wouldn't miss a single feature that you find in an offline desktop Java compiler.

Talking about the mere mortals i.e. "students and beginner programmers", Cloud 9 also has a free tier that offers one free public workspace, one private space, and a bit more which is more than enough to get started free of cost.

Follow the link to access the Cloud 9 online Java compiler: https://aws.amazon.com/cloud9/

When we access the above URL, it opens the following page:

CodeInterview

It has a specific purpose and tat is to hire developers remotely by conducting online interviews. Interviewers can create coding sessions and create with multiple candidates, who can work on the problems live in the browser and submit the code for executions.

Follow the link to access the CodeInterview online Java compiler: https://codeinterview.io/

When we access the above URL, it opens the following page:

There are a lot of online compilers available on internet these days. And the features available in offline tools are also taken care of in many online compiler tools.

The world of online compilers might move more towards use case-specific tools. For example, CodeInterview is a type of an online Java compiler but focused mainly on creating sessions for conducting online interviews.

JDoodle, ReplIt, etc. focuses more on student-teacher communication, where assignment creation and sharing become absolutely easy. AWS Cloud9 is an enterprise-grade development environment. So, we can say that online compilers are equally important and used as much as offline tools.