Project Title

langchain4j — Simplify LLM Integration into Java Applications with Unified APIs

Overview

LangChain4j is an open-source Java library designed to streamline the integration of Large Language Models (LLMs) into Java applications. It offers a unified API for various LLM providers and embedding stores, a comprehensive toolbox for building LLM-powered applications, and numerous examples to get started quickly. This library stands out for its ease of use and the ability to switch between different LLMs and embedding stores without rewriting code.

Key Features

Unified API for integrating 15+ popular LLM providers and 15+ embedding stores.
Comprehensive toolbox with practical code for common LLM-powered application patterns.
Numerous examples for quick inspiration and starting points for building LLM-powered applications.

Use Cases

Building chatbots that can switch between different LLM providers without code changes.
Developing Retrieval-Augmented Generation (RAG) applications with a complete pipeline from data ingestion to retrieval.
Creating applications that leverage different embedding stores for vector database management.

Advantages

Easy switching between LLMs and embedding stores without code rewrites.
Active development and quick incorporation of new techniques and integrations.
A wide variety of options for building various LLM-powered applications.

Limitations / Considerations

Some features are still under development, and the library is not yet fully mature.
The project's documentation and community support are still growing, which might affect the ease of getting started for some developers.

OpenAI's GPT: A popular LLM provider with a Python library, differing in that it is not a Java library and does not offer the unified API approach of LangChain4j.
Hugging Face's Transformers: A Python library for NLP that includes support for various LLMs, differing in that it is not Java-based and does not focus on the unified API approach.
JAX-RS: A Java API for RESTful Web Services, differing in that it is not specifically designed for LLM integration but rather for building RESTful services.

Basic Information

GitHub: https://github.com/langchain4j/langchain4j
Stars: 9,162
License: Unknown
Last Commit: 2025-10-01

📊 Project Information

Project Name: langchain4j
GitHub URL: https://github.com/langchain4j/langchain4j
Programming Language: Java
⭐ Stars: 9,162
🍴 Forks: 1,688
📅 Created: 2023-06-20
🔄 Last Updated: 2025-10-01

🏷️ Project Topics

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