ADK for Java opening up to third-party language models via LangChain4j integration- Google Developers Blog

What this post added

This post details the integration of the Agent Development Kit (ADK) for Java with the LangChain4j LLM framework in version 0.2.0. It explains how this integration allows developers to leverage a wide array of third-party and local Large Language Models (LLMs) beyond ADK's built-in Google Gemini and Anthropic Claude. The post provides concrete Java code examples for using Gemma 3 with Docker Model Runner and Qwen 3 with Ollama, demonstrating how to configure ADK agents with these external models via the `LangChain4j` bridge class. It also highlights other new features in the release, such as instance-based `FunctionTools`, improved async support for `FunctionTools`, programmatic control over agent loop execution with `endInvocation`, chained callbacks for agent lifecycle events, and new memory/retrieval services (`InMemoryMemoryService`, `VertexAiRagRetrieval`).