A qualitative comparison of JVM languages from the developer's perspective

Abstract

This study focuses on three representative languages in the JVM ecosystem: mature Java, modern Kotlin, and Scala, which incorporates functional programming. Unlike most quantitative studies that focus on performance benchmarks, this study takes a qualitative approach and delves into the developer experience of these languages in real-world applications through semi-structured interviews with senior developers. We find that Java's long-term stability and large ecosystem remain its core strengths; Kotlin is highly recognized for its productivity, simplicity, and safety. Scala's expressive power and flexibility make it particularly useful in specific, complex domains. The study further reveals the key factors that affect the choice of technology, including the learning curve of the language, the degree of integration with the existing tool chain, and the impact on the long-term maintainability of the project. This study provides insights based on real-world experience for development teams when choosing JVM languages, and highlights the importance of developer experience in technology evolution and decision making.