Development Tools

Javalin – simple web framework for Java and Kotlin

Javalin is a simple web framework for Java and Kotlin.

Javalin’s main goals are simplicity, a great developer experience, and first class interoperability between Kotlin and Java.

This is free and open source software.

Features include:

  • Simple – very few concepts that you need to learn. You never extend classes and you rarely implement interfaces.
  • Lightweight – just a few thousand lines of code on top of Jetty, and its performance is equivalent to raw Jetty code. Due to its size, it’s very easy to reason about the source code
  • Interoperable – made with inter-operability in mind, apps are built the same way in both Java and Kotlin.
  • Flexible – esigned to be simple and blocking, as this is the easiest programming model to reason about. But, if you set a Future as a result, Javalin switches into asynchronous mode.
  • Supports OpenAPI with its – OpenAPI plugin, allows to generate the OpenAPI specification from the application source code.
  • Jetty – runs on top of Jetty, one of the most used and stable web-servers on the JVM. You can configure the Jetty server fully, including SSL and HTTP2 and everything else that Jetty offers.

Support: GitHub Code Repository
Developer: David Åse and many contributors
License: Apache License 2.0

Javalin is written in Kotlin and Java. Learn Kotlin with our recommended free books and free tutorials. Learn Java with our recommended free books and free tutorials.

Return to Java Microframeworks | Return to Kotlin Web Frameworks

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