IntelliJ IDEA

IntelliJ IDEA is the premier IDE for Java and Kotlin. v2025.1 introduces Java 24 support, K2 Mode (Beta/Stable), and a unified AI Assistant.

When to Use

• Java/Kotlin: Unbeatable refactoring and static analysis.
• Spring Boot: Deep understanding of Spring beans and endpoints.
• Large Monorepos: Indexing is smarter and incremental.

Core Concepts

Indexing

IntelliJ builds a massive index of your code. This enables "Find Usages" to be instant and 100% accurate.

Intentions (Alt+Enter)

The magic key. Fixes warnings, optimizes imports, converts Java to Kotlin.