Kotlin is a modern alternative to Java on the JVM. Less boilerplate, null safety, coroutines.
Kotlin Advantages¶
- Null safety in the type system
- Data classes, extension functions
- Coroutines for async
- Less boilerplate
- Full interop with Java
Java Advantages¶
- Largest ecosystem
- Java 21+ features (records, sealed, pattern matching)
- More Java developers on the market
- Spring Boot dominance
- More stable for large teams
Example¶
// Java public record User(String name, String email) {} // Kotlin data class User(val name: String, val email: String)
When to Use Which¶
- Kotlin — Android, new backend projects, Spring Boot
- Java — enterprise legacy, large teams, stability
Kotlin for New Projects¶
Java for existing enterprise. Kotlin for new code on the JVM.
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