Comparing Top Gen AI Frameworks for Java in 2026

Java has always been a serious language for production systems, and in 2026, the Generative AI ecosystem has finally caught up. For years, Java developers watched from the sidelines as Python and TypeScript accumulated framework after framework for building LLM-powered applications. Today, the picture is very different. Java has multiple mature, actively maintained AI frameworks, each with its own philosophy and trade-offs. This article covers the four frameworks I have personally used to ship Java AI applications: Genkit Java, Spring AI, LangChain4j, and Google ADK Java.