Groovy functional interfaces and SAM type coercion with 12 examples. Covers closure conversion, Java interop, and custom SAM types. Tested on Groovy 5.x. “The best interface is the one you don’t have to think about – Groovy’s SAM coercion makes Java’s functional interfaces disappear into closures.” Brian Goetz, Java Concurrency in Practice Last Updated: March 2026 | Tested on: Groovy 5.x, Java 17+ | Difficulty: Intermediate to Advanced | Reading Time: 20 minutes If you’ve been writing Groovy alongside Java, ... Read More