langchain4j-spring-boot-integration

LangChain4j Spring Boot Integration

Integrate LangChain4j with Spring Boot using declarative AI Services, auto-configuration, and Spring Boot starters. Configure AI model beans, set up chat memory, implement RAG pipelines with Spring Data, and build production-ready AI applications.

When to Use

Use this skill when:

• Integrating LangChain4j into existing Spring Boot applications
• Building AI-powered microservices with Spring Boot
• Configuring AI model beans with @Bean annotations
• Setting up auto-configuration for AI models and services
• Creating declarative AI Services with Spring dependency injection
• Implementing RAG systems with Spring Data integrations
• Setting up chat memory with Spring context management
• Configuring multiple AI providers (OpenAI, Azure, Ollama, Anthropic)
• Building production-ready AI applications with Spring Boot

Overview

LangChain4j Spring Boot integration provides declarative AI Services through Spring Boot starters, enabling automatic configuration of AI components based on properties. Combine Spring dependency injection with LangChain4j's AI capabilities using interface-based definitions with annotations.

Instructions

1. Add Dependencies

<!-- Core LangChain4j Spring Boot Starter -->
<dependency>
    <groupId>dev.langchain4j</groupId>
    <artifactId>langchain4j-spring-boot-starter</artifactId>
    <version>1.8.0</version>
</dependency>

<!-- OpenAI Spring Boot Starter -->
<dependency>
    <groupId>dev.langchain4j</groupId>
    <artifactId>langchain4j-open-ai-spring-boot-starter</artifactId>
    <version>1.8.0</version>
</dependency>

2. Configure Application Properties

# application.properties
langchain4j.open-ai.chat-model.api-key=${OPENAI_API_KEY}
langchain4j.open-ai.chat-model.model-name=gpt-4o-mini
langchain4j.open-ai.chat-model.temperature=0.7
langchain4j.open-ai.chat-model.timeout=PT60S
langchain4j.open-ai.chat-model.max-tokens=1000

Or using YAML:

langchain4j:
  open-ai:
    chat-model:
      api-key: ${OPENAI_API_KEY}
      model-name: gpt-4o-mini
      temperature: 0.7
      timeout: 60s
      max-tokens: 1000