CoAP协议接入 - Java代码示例

import org.eclipse.californium.core.CoapClient;
import org.eclipse.californium.core.CoapHandler;
import org.eclipse.californium.core.CoapObserveRelation;
import org.eclipse.californium.core.CoapResponse;
import org.eclipse.californium.core.coap.CoAP.Code;
import org.eclipse.californium.core.coap.CoAP.Type;
import org.eclipse.californium.core.coap.Request;
import org.eclipse.californium.elements.exception.ConnectorException;

import java.io.IOException;
import java.net.URISyntaxException;

public class IotCoapClientWithDocument {
    //需要确认coap ip与端口号
    private static String ip = "127.0.0.1:5683";
    private static String clientid = "V6BHPcM3GBuYm8GaCBiudrVv3.DcYTq21176109566006710274**securemode*2,signmethod*hmacsha256,timestamp*1700472181602**";
    private static String username = "DcYTq21176109566006710274$V6BHPcM3GBuYm8GaCBiudrVv3";
    private static String password = "bde537588a6867cfc0b2f319bc6dc7654a9716ebf1c2c5d497404fb98134b598";
    private static String PUBLISH_TOPIC = "/ps/product1/device1/thing/heart";
    private static String SUBSCRIBE_TOPIC = "/ps/product1/device1/thing/heart/response";

    // CoAP客户端。
    private CoapClient coapClient = new CoapClient();

    private String token = "1";

    public static void main(String[] args) throws InterruptedException, URISyntaxException {
        IotCoapClientWithDocument client = new IotCoapClientWithDocument();
        client.setToken();
        // start a new thread to client.get();
        var thread = new Thread(client::get);
        thread.start();
        Thread.sleep(1000);
        client.publishDas("{\"data\":{\"heart\":1}}");
        thread.join();
    }

    /**
     * 发送消息。
     *
     * @param payload，消息内容。
     */
    public void publishDas(String payload) {
        try {
            String uri = "coap://" + ip + PUBLISH_TOPIC + "?clientid=" + clientid + "&token=" + token;

            Request request = new Request(Code.POST, Type.CON);

            // 设置消息发布uri。
            request.setURI(uri);

            // 设置消息payload。
            request.setPayload(payload);

            // 发送消息。
            CoapResponse response = coapClient.advanced(request);
        } catch (ConnectorException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void get() {
        String uri = "coap://" + ip + SUBSCRIBE_TOPIC + "?clientid=" + clientid + "&token=" + token;
        final CoapClient client = new CoapClient(uri);
        CoapObserveRelation relation = client.observe(new CoapHandler() {
            @Override
            public void onLoad(CoapResponse response) {
                // 处理接收到的消息
                String payload = response.getResponseText();
                // 在这里执行您的逻辑
                System.out.println(payload);
            }

            @Override
            public void onError() {
                // 处理错误
            }
        });
    }

    public String setToken() throws URISyntaxException {
        Request request = new Request(Code.POST, Type.CON);
        // 设置消息发布uri。
        request.setURI("coap://" + ip + "/mqtt/connection?clientid=" + clientid + "&username=" + username + "&password=" + password);
        // 发送消息。
        CoapResponse response = null;
        try {
            response = coapClient.advanced(request);
        } catch (ConnectorException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        token = response.getResponseText();
        return response.getResponseText();
    }
}