基于springboot设计能接入 http mqtt coap协议的物联网平台，写出示范代码，包含依赖项，import语句

以下是基于Spring Boot设计的示范代码，可接入HTTP、MQTT和CoAP协议的物联网平台。需要注意的是，由于使用了MQTT和CoAP依赖项，因此需要在pom.xml文件中添加相应的依赖项。

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.integration.annotation.IntegrationComponentScan;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.channel.DirectChannel;
import org.springframework.integration.channel.PublishSubscribeChannel;
import org.springframework.integration.config.EnableIntegration;
import org.springframework.integration.core.MessageProducer;
import org.springframework.integration.mqtt.inbound.MqttPahoMessageDrivenChannelAdapter;
import org.springframework.integration.mqtt.outbound.MqttPahoMessageHandler;
import org.springframework.integration.mqtt.support.DefaultPahoMessageConverter;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.MessageHandler;
import org.springframework.messaging.MessageHeaders;
import org.springframework.messaging.MessagingException;
import org.springframework.messaging.support.MessageBuilder;

@SpringBootApplication
@EnableIntegration
@IntegrationComponentScan
public class IotPlatformApplication {

    public static void main(String[] args) {
        SpringApplication.run(IotPlatformApplication.class, args);
    }

    // HTTP入站通道
    @Bean
    public MessageChannel httpInboundChannel() {
        return new DirectChannel();
    }

    // HTTP出站通道
    @Bean
    public MessageChannel httpOutboundChannel() {
        return new DirectChannel();
    }

    // MQTT入站通道
    @Bean
    public MessageChannel mqttInboundChannel() {
        return new DirectChannel();
    }

    // MQTT出站通道
    @Bean
    public MessageChannel mqttOutboundChannel() {
        return new DirectChannel();
    }

    // CoAP入站通道
    @Bean
    public MessageChannel coapInboundChannel() {
        return new DirectChannel();
    }

    // CoAP出站通道
    @Bean
    public MessageChannel coapOutboundChannel() {
        return new DirectChannel();
    }

    // HTTP请求处理器
    @Bean
    @ServiceActivator(inputChannel = "httpInboundChannel")
    public MessageHandler httpHandler() {
        return message -> {
            // 处理HTTP请求
            MessageHeaders headers = message.getHeaders();
            // 获取HTTP请求参数
            // ...
            // 返回HTTP响应
            MessageChannel replyChannel = (MessageChannel) headers.getReplyChannel();
            replyChannel.send(MessageBuilder.withPayload("HTTP response").build());
        };
    }

    // MQTT消息监听器
    @Bean
    public MessageProducer mqttInbound() {
        MqttPahoMessageDrivenChannelAdapter adapter =
                new MqttPahoMessageDrivenChannelAdapter("tcp://localhost:1883", "clientId", "topic");
        adapter.setCompletionTimeout(5000);
        adapter.setConverter(new DefaultPahoMessageConverter());
        adapter.setQos(1);
        adapter.setOutputChannel(mqttInboundChannel());
        return adapter;
    }

    // MQTT消息处理器
    @Bean
    @ServiceActivator(inputChannel = "mqttInboundChannel")
    public MessageHandler mqttHandler() {
        return message -> {
            // 处理MQTT消息
            String payload = message.getPayload().toString();
            // ...
            // 发布MQTT响应
            MqttPahoMessageHandler handler = new MqttPahoMessageHandler("tcp://localhost:1883", "clientId");
            handler.setDefaultTopic("responseTopic");
            handler.setAsync(true);
            handler.setDefaultQos(1);
            handler.setDefaultRetained(false);
            handler.handleMessage(MessageBuilder.withPayload("MQTT response").build());
        };
    }

    // CoAP请求处理器
    @Bean
    @ServiceActivator(inputChannel = "coapInboundChannel")
    public MessageHandler coapHandler() {
        return message -> {
            // 处理CoAP请求
            MessageHeaders headers = message.getHeaders();
            // 获取CoAP请求参数
            // ...
            // 返回CoAP响应
            MessageChannel replyChannel = (MessageChannel) headers.getReplyChannel();
            replyChannel.send(MessageBuilder.withPayload("CoAP response").build());
        };
    }

    // CoAP服务器
    @Bean
    public CoapServer coapServer() {
        CoapServer server = new CoapServer();
        server.add(new CoapResource("coapResource") {
            @Override
            public void handleGET(CoapExchange exchange) {
                // 将CoAP请求转换成Spring Integration消息
                Message<byte[]> message = MessageBuilder.withPayload(exchange.getRequestPayload())
                        .setHeader("replyChannel", coapOutboundChannel())
                        .build();
                // 发送消息到CoAP入站通道
                coapInboundChannel().send(message);
                // 接收CoAP响应消息
                Message<?> response = (Message<?>) coapOutboundChannel().receive();
                // 将Spring Integration消息转换成CoAP响应
                exchange.respond(response.getPayload());
            }
        });
        server.start();
        return server;
    }
}

在pom.xml文件中添加以下依赖项：

<dependencies>
    <!-- Spring Boot Starter Web -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    
    <!-- Spring Integration -->
    <dependency>
        <groupId>org.springframework.integration</groupId>
        <artifactId>spring-integration-core</artifactId>
    </dependency>
    
    <!-- Spring Integration MQTT -->
    <dependency>
        <groupId>org.springframework.integration</groupId>
        <artifactId>spring-integration-mqtt</artifactId>
    </dependency>
    
    <!-- Californium CoAP -->
    <dependency>
        <groupId>org.eclipse.californium</groupId>
        <artifactId>californium-core</artifactId>
    </dependency>
    
    <!-- Californium CoAP Blockwise -->
    <dependency>
        <groupId>org.eclipse.californium</groupId>
        <artifactId>californium-core-blockwise</artifactId>
    </dependency>
    
    <!-- Californium CoAP Observe -->
    <dependency>
        <groupId>org.eclipse.californium</groupId>
        <artifactId>californium-core-coap-observe</artifactId>
    </dependency>
    
</dependencies>

这是一个基本示例，仅涵盖了HTTP、MQTT和CoAP的入站通道、出站通道和消息处理器。在实际应用中，还需要根据具体业务需求进行进一步的开发。