Hello-LangChain4j

reference:

1. https://langchain4j.github.io/langchain4j/
2. https://github.com/feuyeux/hello-langchain

About LangChain4j

2 levels of abstraction

1. Low level: the "primitives" of your LLM-powered application. You have complete control over how to combine them, but you will need to write more code in the imperative style.
2. High level: At this level, you interact with LLMs using high-level APIs like AiServices and Chains, which hides all the complexity and boilerplate from you.