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Your dated Java apps can now be converted into JavaScript using CheerpJ

Java apps conversion using CheerpJ

CheerpJ is a new compiler technology that converts Java bytecodes into JavaScript. The tool is designed to help you transform your old Java apps for web development.

Without requiring any plugin or Java installation, CheerpJ is an easy solution to convert client-side browser-based libraries while the native code can continue to be used as platform-independent components for Node.js. The tool also has an offline compiler that helps you move Java bytecode to JavaScript in the runtime environment. Additionally, you can use the compiler for deploying classes alongside with the applications.

“The main purpose of CheerpJ is to allow developers to convert legacy Java code into browser-based Web applications, thereby not requiring any Java installation on the client side,” writes CheerpJ creator Stefano De Rossi, who is a researcher in wearable robotics at Harvard, in a blog post.

The bidirectional interoperability offered by the tool makes it easier to invoke any JS library or API from Java. Notably, the tool deploys the converted apps on the web server in both .js and .jar formats.

Perfect for converting older versions

CheerpJ is not the only solution to offer conversion. Google Web Toolkit is also capable of converting Java apps but lacks full support for Java contributions. Therefore, the limitations in exiting tools and platforms make them well-suited for newer apps, whereas CheerpJ is capable of converting even the older Java apps and libraries.

The tool will be published as a restricted release in July this year. You can expect its general availability and a commercial version by November. Furthermore, the tool will also release in a Chrome extension that will enable Java applets without Java plugin or installation.