Search code examples
javaspring-bootiotcoap

Unable to start the Coap server in a Spring boot application

I am trying to add a Coap server through Eclipse Californium in a Java Spring boot-based application. Below are the codes.

import org.eclipse.californium.core.CoapServer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class CoapServerConfiguration {

     @Bean
    public CoapServer coapServer() {
         int portNumber = 9995;
         CoapServer coapServer= null;
            try {
             coapServer = new CoapServer(portNumber);
             coapServer.add();
            }catch(Exception e) {e.printStackTrace();}
        // Add your CoAP resources here
        // server.add(new YourCoapResource());

      //  System.out.println("Coap server started");
        return coapServer;
    }
}

However, when I start the application, I get the following error.

java.lang.IllegalStateException: Configuration contains no definitions!
    at org.eclipse.californium.elements.config.Configuration.add(Configuration.java:802)
    at org.eclipse.californium.elements.config.Configuration.load(Configuration.java:772)
    at org.eclipse.californium.elements.config.Configuration.load(Configuration.java:738)
    at org.eclipse.californium.elements.config.Configuration.createWithFile(Configuration.java:628)
    at org.eclipse.californium.elements.config.Configuration.createStandardWithFile(Configuration.java:588)
    at org.eclipse.californium.elements.config.Configuration.getStandard(Configuration.java:458)
    at org.eclipse.californium.core.CoapServer.<init>(CoapServer.java:184)
    at com.dropbydrop.smartmeter.CoapServerConfiguration.coapServer(CoapServerConfiguration.java:16)

I have added the following dependencies also,in this application.

<dependency>
    <groupId>org.eclipse.californium</groupId>
    <artifactId>californium-core</artifactId>
    <version>3.9.0</version>
</dependency>

   
<!-- https://mvnrepository.com/artifact/org.eclipse.californium/element-connector -->
<dependency>
    <groupId>org.eclipse.californium</groupId>
    <artifactId>element-connector</artifactId>
    <version>3.9.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.36</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.eclipse.californium/californium-legal -->
<dependency>
    <groupId>org.eclipse.californium</groupId>
    <artifactId>californium-legal</artifactId>
    <version>3.9.0</version>
    <scope>runtime</scope>
</dependency>
Solution

  • Starting with Californium 3.0, the configuration uses modules. Before using the configuration, the required modules must be registered. See Config.register()