Kotlin is a general-purpose, free, open-source, statically typed “pragmatic” programming language initially designed for the JVM (Java Virtual Machine) and Android. It combines both object-oriented and functional programming features, offering a versatile and powerful tool for developers. Kotlin emphasizes interoperability, safety, clarity, and robust tooling support, making it an attractive choice for modern development needs. Additionally, versions of Kotlin targeting JavaScript ES5.1 and native code (using LLVM) for various processors are also in production, broadening its application scope.
Kotlin was developed by JetBrains, the company behind the popular IntelliJ IDEA, starting in 2010 and became open source in 2012. Since its open-source release, Kotlin has garnered significant community support, with the Kotlin project on GitHub boasting over 770 contributors. While the core team primarily consists of JetBrains employees, the project has also benefited from nearly 100 external contributors, reflecting a strong collaborative effort. JetBrains itself utilizes Kotlin extensively in many of its products, including IntelliJ IDEA, showcasing its confidence in the language’s capabilities.
One of Kotlin’s standout features is its seamless interoperability with Java. Kotlin is fully compatible with Java, allowing developers to use both languages within the same project. This compatibility means that existing Java codebases can be incrementally migrated to Kotlin without needing a complete rewrite. This feature is particularly valuable for large enterprise projects where transitioning to a new language can be a daunting and resource-intensive task.
Kotlin also addresses several pain points associated with Java. It reduces boilerplate code, resulting in more concise and readable programs. Kotlin’s type inference allows developers to write more expressive and less verbose code. Moreover, Kotlin introduces null safety by design, significantly reducing the risk of null pointer exceptions, a common issue in Java development. These enhancements lead to more maintainable and reliable code.
The adoption of Kotlin has been particularly prominent in Android development. In 2017, Google announced official support for Kotlin on Android, which accelerated its adoption within the Android community. Kotlin’s expressive syntax and modern features make it well-suited for developing Android applications, providing a more enjoyable and efficient development experience compared to Java. Many top Android apps now leverage Kotlin, underscoring its growing influence in the mobile development landscape.
Beyond mobile and JVM development, Kotlin’s capabilities extend to web and native development. Kotlin/JS allows developers to write Kotlin code that compiles to JavaScript, enabling the creation of full-stack web applications. Kotlin/Native, on the other hand, targets platforms where a JVM is not feasible, such as iOS or embedded systems, by compiling Kotlin code to native binaries using LLVM. This flexibility makes Kotlin a compelling choice for cross-platform development, allowing developers to use a single language across different platforms and environments.
In summary, Kotlin offers significant advantages over Java for JVM and Android development, including enhanced readability, reduced boilerplate, and null safety. Its interoperability with Java facilitates smooth transitions and incremental codebase improvements. With its support for web and native development, Kotlin is a versatile and powerful tool that caters to a wide range of development needs, solidifying its position as a modern alternative to Java.