背景#

决定入手Spring AI。有几个原因：

Spring AI项目生成#

一样的，使用spring initializr生成项目骨架。

spring-initializr

  • 和普通的Spring Boot的web项目一样，选择Spring Web依赖即可。
  • 为了开发调试，选择Spring Boot DevTools依赖。
  • 为了方便问题排查，选择Spring Boot Actuator依赖。
  • 选择Java 25版本 + Gradle。

项目#

功能#

实现一个简单的QA对话，用户输入一个问题，调用OpenAI的API获取回答并返回给用户。

官方文档Chat Client API

代码实现#

接口定义

public interface BoardGameService {
    Answer askQuestion(Question question);
}

public record Answer(String answer) {
}

public record Question(String question) {
}

实现类

@Service
public class SpringAiBoardGameService implements BoardGameService {

    private final ChatClient chatClient;

    public SpringAiBoardGameService(ChatClient.Builder chatClientBuilder) {
        this.chatClient = chatClientBuilder.build();
    }

    @Override
    public Answer askQuestion(Question question) {
        var answerText = chatClient.prompt()
        .user(question.question())
        .call()
        .content();
        return new Answer(answerText);
    }
}

web层

@Controller
public class AskController {
    private final BoardGameService boardGameService;

    public AskController(BoardGameService boardGameService) {
        this.boardGameService = boardGameService;
    }

    @PostMapping(path = "/ask", produces = "application/json")
    public Answer ask(@RequestBody Question question) {
        return boardGameService.askQuestion(question);
    }
}

配置#

application.yaml配置文件内容如下：

spring:
  application:
    name: spring-ai-demo
  ai:
    openai:
      api-key: ${OPENAI_API_KEY}
      base-url: https://api.openai.com

management:
  endpoints:
    web:
      exposure:
        include: "*"

运行#

OpenAI的API key需要付费账户才能使用。免费账户就算生成了API key也是无法调用的。会报429 Too Many Requests错误。

openai_429

OpenAI API兼容性#

Spring AI支持多种AI模型提供商。虽然不同的提供商有各自不同的私有API，但是很多提供商都实现了OpenAI API的兼容接口。某种程度来说，大家都在copy OpenAI的API设计，目前OpenAI的API设计已经成为事实上的标准。

切换到Gemini#

将application.yaml中的配置修改为：

spring:
  application:
    name: spring-ai-demo
  ai:
    # openai:
    #   api-key: your openai-api-key
    #   base-url: https://api.openai.com
    google:
      genai:
        api-key: ${GOOGLE_GENAI_API_KEY}

management:
  endpoints:
    web:
      exposure:
        include: "*"

然后将环境变量GOOGLE_GENAI_API_KEY设置为你的Gemini API key即可。

可以到Google AI Studio创建API key。

依赖实现也需要切换

--implementation("org.springframework.ai:spring-ai-starter-model-openai")
++implementation("org.springframework.ai:spring-ai-starter-model-google-genai")

org.springframework.ai.chat.client.ChatClient会自动切换到Google Gemini的实现。

测试# 

http :8080/ask question="What's the weather in singapore today?"
HTTP/1.1 200 
Connection: keep-alive
Content-Type: application/json
Date: Sun, 16 Nov 2025 15:37:29 GMT
Keep-Alive: timeout=60
Transfer-Encoding: chunked

{
    "answer": "I do not have access to real-time weather information. To find out the weather in Singapore today, I recommend checking a reliable weather source such as:\n\n*   **Google Weather:** Simply search \"weather in Singapore\" on Google.\n*   **National Environment Agency (NEA) Singapore:** Their website ([nea.gov.sg](https://www.nea.gov.sg/)) provides detailed weather forecasts and information.\n*   **AccuWeather:** ([accuweather.com](https://www.accuweather.com/))\n*   **The Weather Channel:** ([weather.com](https://weather.com/))\n\nThese sources will give you the most up-to-date and accurate weather information for Singapore.\n"
}

总结#

Spring AI提供了一个非常方便的方式来集成各种AI模型服务。通过统一的API接口，可以轻松切换不同的AI提供商，降低了集成的复杂度。

上面的例子通过切换配置，实现了从OpenAI到Google Gemini的无缝切换，展示了Spring AI的强大功能和灵活性。如果本地搭建了Ollama等支持OpenAI API的服务，也可以通过类似的方式进行集成。

源码#