Java MCP 实战之如何构建跨进程与远程的工具服务

<dependency>
    <groupId>org.noear</groupId>
    <artifactId>solon-ai-mcp</artifactId>
    <version>最新版本</version>
</dependency>

@McpServerEndpoint(sseEndpoint = "/mcp/sse")
public class SimpleMcpServer {
    @ToolMapping(description = "问候服务")
    public String hello(@Param(name="name", description = "用户名") String name) {
        return "你好, " + name;
    }
}
public class App {
    public static void main(String[] args) {
        Solon.start(App.class, args);
    }
}

// 金融工具服务
@McpServerEndpoint(name="finance-tools", sseEndpoint = "/finance/sse")
public class FinanceTools {
    @ToolMapping(description = "计算复利")
    public double compoundInterest(
            @Param(description = "本金") double principal,
            @Param(description = "年利率") double rate,
            @Param(description = "年数") int years) {
        return principal * Math.pow(1 + rate, years);
    }
}
// 教育工具服务
@McpServerEndpoint(name="edu-tools", sseEndpoint = "/edu/sse")
public class EducationTools {
    @ToolMapping(description = "生成数学题")
    public String generateMathProblem(
            @Param(description = "难度级别") String level) {
        if("easy".equals(level)) {
            return "3 + 5 = ?";
        } else {
            return "∫(x^2)dx from 0 to 1 = ?";
        }
    }
}

@Controller
public class ToolManager {
    @Inject("finance-tools")
    McpServerEndpointProvider financeEndpoint;
    @Mapping("/tool/add")
    public void addTool() {
        financeEndpoint.addTool(new FunctionToolDesc("calculateTax")
            .doHandle(params -> {
                double income = (double)params.get("income");
                return income * 0.2; // 简单计算20%税
            }));
        financeEndpoint.notifyToolsListChanged();
    }
    @Mapping("/tool/remove")
    public void removeTool() {
        financeEndpoint.removeTool("calculateTax");
        financeEndpoint.notifyToolsListChanged();
    }
}

@McpServerEndpoint(channel = McpChannel.STDIO)
public class StdioCalculator {
    @ToolMapping(description = "加法计算")
    public int add(@Param int a, @Param int b) {
        return a + b;
    }
    @ToolMapping(description = "减法计算")
    public int subtract(@Param int a, @Param int b) {
        return a - b;
    }
}

public class McpClientDemo {
    public static void main(String[] args) {
        // 连接SSE服务
        McpClientToolProvider sseClient = McpClientToolProvider.builder()
            .apiUrl("http://localhost:8080/mcp/sse")
            .build();
        String greeting = sseClient.callToolAsText("hello", Map.of("name", "张三"));
        System.out.println(greeting);
        // 连接STDIO服务
        McpClientToolProvider stdioClient = McpClientToolProvider.builder()
            .channel(McpChannel.STDIO)
            .serverParameters(McpServerParameters.builder("java")
                .args("-jar", "path/to/stdio-service.jar")
                .build())
            .build();
        int sum = stdioClient.callToolAsText("add", Map.of("a", 5, "b", 3));
        System.out.println("5 + 3 = " + sum);
    }
}

@Configuration
public class AiConfig {
    @Bean
    public ChatModel chatModel(
            @Inject("${solon.ai.chat.config}") ChatConfig chatConfig,
            @Inject("mcp-weather") McpClientToolProvider toolProvider) {
        return ChatModel.of(chatConfig)
            .defaultToolsAdd(toolProvider.getTools())
            .build();
    }
    @Bean("mcp-weather")
    public McpClientToolProvider weatherToolProvider() {
        return McpClientToolProvider.builder()
            .apiUrl("http://weather-service/mcp/sse")
            .build();
    }
}
@Service
public class WeatherService {
    @Inject
    ChatModel chatModel;
    public String askWeather(String question) {
        ChatResponse response = chatModel.prompt(question).call();
        return response.getContent();
    }
}

@McpServerEndpoint(sseEndpoint = "/mcp/sse")
public class FullFeatureServer {
    // 工具服务
    @ToolMapping(description = "汇率转换")
    public double exchangeRate(
            @Param(description = "源货币") String from,
            @Param(description = "目标货币") String to) {
        // 实现汇率转换逻辑
        return 6.5;
    }
    // 资源服务
    @ResourceMapping(uri = "config://app-info", 
                   description = "获取应用信息")
    public String getAppInfo() {
        return "AppName: WeatherService, Version: 1.0.0";
    }
    // 提示语服务
    @PromptMapping(description = "生成天气报告提示")
    public Collection<ChatMessage> weatherReportPrompt(
            @Param(description = "城市名称") String city) {
        return Arrays.asList(
            ChatMessage.ofSystem("你是一个天气报告助手"),
            ChatMessage.ofUser("请生成" + city + "的天气报告")
        );
    }
}

// 将STDIO服务代理为SSE服务
@McpServerEndpoint(sseEndpoint = "/proxy/sse")
public class StdioToSseProxy implements ToolProvider {
    private McpClientProvider stdioClient = McpClientProvider.builder()
        .channel(McpChannel.STDIO)
        .serverParameters(ServerParameters.builder("java")
            .args("-jar", "path/to/stdio-service.jar")
            .build())
        .build();
    @Override
    public Collection<FunctionTool> getTools() {
        return stdioClient.getTools();
    }
}
// 将SSE服务代理为STDIO服务
@McpServerEndpoint(channel = McpChannel.STDIO)
public class SseToStdioProxy implements ToolProvider {
    private McpClientProvider sseClient = McpClientProvider.builder()
        .apiUrl("http://remote-service/mcp/sse")
        .build();
    @Override
    public Collection<FunctionTool> getTools() {
        return sseClient.getTools();
    }
}

@Controller
@McpServerEndpoint(sseEndpoint = "/mcp/sse")
public class HybridService {
    // 同时作为Web API和MCP工具
    @ToolMapping(description = "查询库存")
    @Mapping("/api/inventory")
    public int getInventory(
            @Param(description = "产品ID") String productId,
            @Header("Authorization") String auth) {
        // 验证逻辑...
        return 100; // 示例库存
    }
    // 纯Web API
    @Mapping("/api/info")
    public String getInfo() {
        return "Service Info";
    }
    // 纯MCP工具
    @ToolMapping(description = "计算折扣")
    public double calculateDiscount(
            @Param(description = "原价") double price,
            @Param(description = "会员等级") String level) {
        if("VIP".equals(level)) {
            return price * 0.8;
        }
        return price;
    }
}

@Component
public class McpAuthFilter implements Filter {
    @Override
    public void doFilter(Context ctx, FilterChain chain) throws Throwable {
        if (ctx.pathNew().startsWith("/mcp/")) {
            String apiKey = ctx.header("X-API-KEY");
            if(!validateApiKey(apiKey)) {
                ctx.status(401);
                return;
            }
        }
        chain.doFilter(ctx);
    }
}

McpClientToolProvider.builder()
    .apiUrl("http://service/mcp/sse")
    .apiKey("your-api-key")
    .httpTimeout(HttpTimeout.builder()
        .connectTimeout(Duration.ofSeconds(5))
        .readTimeout(Duration.ofSeconds(30))
        .build())
    .requestTimeout(Duration.ofSeconds(20))
    .build();

@McpServerEndpoint(sseEndpoint = "/mcp/sse", heartbeatInterval = "60s")
public class HeartbeatService {
    // ...
}