Programming languages · Comparison
Kotlin vs Java
Both run on the JVM, share libraries and can live in the same project. Kotlin is the newer, more concise option that Google recommends for Android; Java is the long-established standard for enterprise backends.
2 options · 8 questions side by side · updated
| Compare | Kotlin | Java |
|---|---|---|
| Origin | JetBrains, 1.0 in 2016 | Sun Microsystems, 1995; now Oracle |
| Code style | Concise, little boilerplate | More verbose, though modern Java trims a lot |
| Null safety | Built into the type system | Annotations and Optional; null crashes still common |
| Concurrency | Coroutines and Flow | Threads, plus lightweight virtual threads |
| Android | Recommended; Compose is Kotlin-only | Supported, but new APIs are Kotlin-first |
| Servers | Ktor, Spring Boot | Spring Boot, Quarkus and a vast enterprise base |
| Working together | Calls Java libraries directly | Calls Kotlin code, a little less naturally |
| Hiring | Growing pool, concentrated on Android | A very large, long-established pool |
How to choose between Kotlin and Java
- Pick Kotlin for new Android apps, and for JVM projects that want less boilerplate and built-in null safety.
- Pick Java for large existing Java codebases, teams that already know it, and enterprise stacks built around it.
- The two mix freely in one project, so moving from Java to Kotlin can happen gradually.
The options
- KotlinA modern, concise language from JetBrains that Google recommends for Android apps, and that also runs on servers and across platforms.
- JavaA long-established, strongly typed language that runs on the Java Virtual Machine, behind large company systems, banks, many backends and early Android apps.
More comparisons
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- Python vs JavaScriptTwo of the most common first languages. Both are easy to start with and dynamically typed; they differ mostly in where they run and what their ecosystems are built for.
- Rust vs Go vs C++Three compiled languages for fast, low-level or infrastructure code. They make different trade-offs between raw speed, safety and how easy the code is to write and read.
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