Library / SDK
Agents & OrchestrationRetrieval & Memory
LangChain4j
1LLM 2application 3framework 4for 5Java 6developers
the six Ws · specification
W1
Who
Maintained by the LangChain4j community.
W2
What
An LLM application framework for Java with RAG and tool support.
W3
Where
A Java library with Spring and Quarkus integrations.
W4
When
Reach for it when building LLM apps on the JVM.
W5
Why
Idiomatic Java abstractions for LLMs and RAG.
W6
With
Java, LLM providers, and vector stores.
W7
Watch
Community-maintained; Apache-2.0 library only, actively developed. Runs on your JVM.