LangChain4J 最佳实践和性能优化指南

LangChain4J 最佳实践和性能优化指南

目录

• 1. 开发最佳实践
• 2. 性能优化策略
• 3. 成本控制
• 4. 安全性最佳实践
• 5. 监控和故障排除
• 6. 扩展性设计

1. 开发最佳实践

1.1 代码组织结构

// 推荐的项目结构
src/
├── main/java/com/company/ai/
│   ├── config/          // 配置类
│   │   ├── AiConfiguration.java
│   │   └── SecurityConfiguration.java
│   ├── service/         // 业务服务
│   │   ├── ChatService.java
│   │   └── EmbeddingService.java
│   ├── controller/      // REST 控制器
│   │   └── AiController.java
│   ├── model/          // 数据模型
│   │   └── ChatRequest.java
│   └── tools/          // AI 工具
│       └── DatabaseTools.java
└── resources/
    ├── application.yml
    └── prompts/        // 提示模板
        └── templates.txt

1.2 异常处理模式

@ControllerAdvice
public class AiExceptionHandler {
   
   
    
    @ExceptionHandler(ModelException.class)
    public ResponseEntity<ErrorResponse> handleModelException(ModelException e) {
   
   
        log.error("AI模型调用失败", e);
        
        return ResponseEntity.status(HttpStatus.SERVICE_UNAVAILABLE)
                .body(new ErrorResponse("AI服务暂时不可用", "MODEL_ERROR"));
    }
    
    @ExceptionHandler(RateLimitException.class)
    public ResponseEntity<ErrorResponse> handleRateLimit(RateLimitException e) {
   
   
        return ResponseEntity.status(HttpStatus.TOO_MANY_REQUESTS)
                .body(new ErrorResponse("请求过于频繁，请稍后重试", "RATE_LIMIT"));
    }
}

// 重试机制
@Retryable(value = {
   
   Exception.class}, maxAttempts = 3, backoff = @Backoff(delay = 1000))
public String callAiWithRetry(String prompt) {
   
   
    return chatModel.generate(prompt);
}

1.3 配置管理最佳实践

# application.yml - 推荐配置结构
app:
  ai:
    default-timeout: PT30S
    max-retries: 3
    models:
      primary:
        provider: openai
        model-name: gpt-3.5-turbo
        api-key: ${
   
   OPENAI_API_KEY}
      fallback:
        provider: huggingface
        model-name: microsoft/DialoGPT-large
        
    memory:
      max-messages: 20
      cleanup-interval: PT1H
      
    security:
      input-max-length: 10000
      rate-limit: 100

2. 性能优化策略

2.1 连接池优化

@Configuration
public class PerformanceConfiguration {
   
   
    
    @Bean
    public ChatLanguageModel optimizedChatModel() {
   
   
        // 自定义 HTTP 客户端
        OkHttpClient httpClient = new OkHttpClient.Builder()
                .connectionPool(new ConnectionPool(20, 5, TimeUnit.MINUTES))
                .connectTimeout(10, TimeUnit.SECONDS)
                .readTimeout(60, TimeUnit.SECONDS)
                .retryOnConnectionFailure(true)
                .build();
        
        return OpenAiChatModel.builder()
                .apiKey("sk-...")
                .httpClient(httpClient)
                .maxRetries(3)
                .build();
    }
}

2.2 缓存策略

@Service
public class CachedAiService {
   
   
    
    private final ChatLanguageModel chatModel;
    private fi