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Retrieval-Augmented Generation (RAG) \u0026 Knowledge","SDK, Libraries, Frameworks","开源工具","📚 Projects (1974 total)","More information on LangChain4J","General LLM","Projects","其他语言移植版本","Ports to other languages","人工智能","🚀 Specialized Agents","2. Libraries \u0026 Frameworks","Open Source Tools","Chatbots \u0026 Virtual Companions"],"sub_categories":["大语言对话模型及数据","Other sdk/libraries","RAG框架","Tools \u0026 Libraries","Artificial Intelligence","🗣️ Programming Language Agents","Java"],"readme":"# LangChain4j: idiomatic, open-source Java library for building LLM-powered applications on the JVM\n\n[![Build Status](https://img.shields.io/github/actions/workflow/status/langchain4j/langchain4j/main.yaml?branch=main\u0026style=for-the-badge\u0026label=CI%20BUILD\u0026logo=github)](https://github.com/langchain4j/langchain4j/actions/workflows/main.yaml)\n[![Nightly Build](https://img.shields.io/github/actions/workflow/status/langchain4j/langchain4j/nightly_jdk17.yaml?branch=main\u0026style=for-the-badge\u0026label=NIGHTLY%20BUILD\u0026logo=github)](https://github.com/langchain4j/langchain4j/actions/workflows/nightly_jdk17.yaml)\n[![CODACY](https://img.shields.io/badge/Codacy-Dashboard-blue?style=for-the-badge\u0026logo=codacy)](https://app.codacy.com/gh/langchain4j/langchain4j/dashboard)\n\n[![Discord](https://img.shields.io/discord/1156626270772269217?logo=discord\u0026style=for-the-badge)](https://discord.gg/JzTFvyjG6R)\n[![BlueSky](https://img.shields.io/badge/@langchain4j-follow-blue?logo=bluesky\u0026style=for-the-badge)](https://bsky.app/profile/langchain4j.dev)\n[![X](https://img.shields.io/badge/@langchain4j-follow-blue?logo=x\u0026style=for-the-badge)](https://x.com/langchain4j)\n[![Maven Version](https://img.shields.io/maven-central/v/dev.langchain4j/langchain4j?logo=apachemaven\u0026style=for-the-badge)](https://search.maven.org/#search|gav|1|g:\"dev.langchain4j\"%20AND%20a:\"langchain4j\")\n\n\n## Introduction\n\nWelcome!\n\nThe goal of LangChain4j is to simplify integrating LLMs into Java applications.\n\nHere's how:\n1. **Unified APIs:**\n   LLM providers (like OpenAI or Google Vertex AI) and embedding (vector) stores (such as Pinecone or Milvus)\n   use proprietary APIs. LangChain4j offers a unified API to avoid the need for learning and implementing specific APIs for each of them.\n   To experiment with different LLMs or embedding stores, you can easily switch between them without the need to rewrite your code.\n   LangChain4j currently supports [20+ popular LLM providers](https://docs.langchain4j.dev/integrations/language-models/)\n   and [30+ embedding stores](https://docs.langchain4j.dev/integrations/embedding-stores/).\n2. **Comprehensive Toolbox:**\n   Since early 2023, the community has been building numerous LLM-powered applications,\n   identifying common abstractions, patterns, and techniques. LangChain4j has refined these into practical code.\n   Our toolbox includes tools ranging from low-level prompt templating, chat memory management, and function calling\n   to high-level patterns like Agents and RAG.\n   For each abstraction, we provide an interface along with multiple ready-to-use implementations based on common techniques.\n   Whether you're building a chatbot or developing a RAG with a complete pipeline from data ingestion to retrieval,\n   LangChain4j offers a wide variety of options.\n3. **Numerous Examples:**\n   These [examples](https://github.com/langchain4j/langchain4j-examples) showcase how to begin creating various LLM-powered applications,\n   providing inspiration and enabling you to start building quickly.\n\nLangChain4j began development in early 2023 amid the ChatGPT hype.\nWe noticed a lack of Java counterparts to the numerous Python and JavaScript LLM libraries and frameworks,\nand we had to fix that!\n\n**Despite the name, LangChain4j is not a Java port of LangChain (Python) — it is built for Java, not ported to it.**\nIt is an idiomatic Java library designed from the ground up around Java conventions:\ntype safety, POJOs, annotations, interfaces, dependency injection, fluent APIs, and first-class integrations with Quarkus, Spring Boot, Helidon, and Micronaut.\nIts API, internals, and release cycle are independent of the Python LangChain project.\n\nWe actively monitor community developments, aiming to quickly incorporate new techniques and integrations,\nensuring you stay up-to-date.\nThe library is under active development. While some features are still being worked on,\nthe core functionality is in place, allowing you to start building LLM-powered apps now!\n\n\n## Documentation\nDocumentation can be found [here](https://docs.langchain4j.dev).\n\nThe documentation chatbot (experimental) can be found [here](https://chat.langchain4j.dev/).\n\n\n## Getting Started\nGetting started guide can be found [here](https://docs.langchain4j.dev/get-started).\n\n\n## Code Examples\nPlease see examples of how LangChain4j can be used in [langchain4j-examples](https://github.com/langchain4j/langchain4j-examples) repo:\n- [Examples in plain Java](https://github.com/langchain4j/langchain4j-examples/tree/main/other-examples/src/main/java)\n- [Examples with Quarkus](https://github.com/quarkiverse/quarkus-langchain4j/tree/main/samples) (uses [quarkus-langchain4j](https://github.com/quarkiverse/quarkus-langchain4j) dependency)\n- [Example with Spring Boot](https://github.com/langchain4j/langchain4j-examples/tree/main/spring-boot-example/src/main/java/dev/langchain4j/example)\n- [Examples with Helidon](https://github.com/helidon-io/helidon-examples/tree/helidon-4.x/examples/integrations/langchain4j) (uses [io.helidon.integrations.langchain4j](https://mvnrepository.com/artifact/io.helidon.integrations.langchain4j) dependency)\n- [Examples with Micronaut](https://github.com/micronaut-projects/micronaut-langchain4j/tree/0.3.x/doc-examples/example-openai-java) (uses [micronaut-langchain4j](https://micronaut-projects.github.io/micronaut-langchain4j/latest/guide/) dependency)\n\n## Useful Materials\nUseful materials can be found [here](https://docs.langchain4j.dev/useful-materials).\n\n\n## Get Help\nPlease use [Discord](https://discord.gg/JzTFvyjG6R) or [GitHub discussions](https://github.com/langchain4j/langchain4j/discussions)\nto get help.\n\n\n## Request Features\nPlease let us know what features you need by [opening an issue](https://github.com/langchain4j/langchain4j/issues/new/choose).\n\n\n## Contribute\nContribution guidelines can be found [here](https://github.com/langchain4j/langchain4j/blob/main/CONTRIBUTING.md).\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flangchain4j%2Flangchain4j","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Flangchain4j%2Flangchain4j","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flangchain4j%2Flangchain4j/lists"}