How to eliminate '[DUBBO] publishProvider interfaceName is empty ' error in class InMemoryWritableMetadataService ??

[zmapleshine]

• I have searched the issues of this repository and believe that this is not a duplicate.
• I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

• Dubbo version: 2.7.6
• Operating System version: Win10
• Java version: 1.8

Steps to reproduce this issue

1. import spring-cloud-starter-dubb
2. config consumer:

 dubbo:
  consumer:
    check: false
  #    timeout: 5000
  protocol:
    name: dubbo
    port: -1
  cloud:
    subscribed-services: 'spring-cloud-alibaba-dubbo-provider'

3. config provider

dubbo:
  scan:
    base-packages: com.example.test.dubbo.provider.service
  protocol:
    name: dubbo
    port: -1
  registry:
    address: spring-cloud://localhost
  cloud:
    subscribed-services: ''

4. run provider and consumer

Pls. provide [GitHub address] to reproduce this issue.

Expected Result

What do you expected from the above steps？
no error log

Actual Result

What actually happens?

Console print an error log:

2020-05-28 18:41:20.682 [spring-cloud-alibaba-dubbo-consumer,,,,] 22320 --- [           main] .a.d.m.s.InMemoryWritableMetadataService :  [DUBBO] publishProvider interfaceName is empty . providerUrl: consumer://10.176.128.248/com.alibaba.cloud.dubbo.service.DubboMetadataService?application=spring-cloud-alibaba-dubbo-consumer&check=false&dubbo=2.0.2&generic=true&group=spring-cloud-alibaba-dubbo-provider&interface=com.alibaba.cloud.dubbo.service.DubboMetadataService&pid=22320&qos.enable=false&release=2.7

If there is an exception, please attach the exception trace:

Just put your stack trace here!

Reference code:

 public void publishServiceDefinition(URL providerUrl) {
        try {
            String interfaceName = providerUrl.getParameter(INTERFACE_KEY);
            if (StringUtils.isNotEmpty(interfaceName)
                    && !ProtocolUtils.isGeneric(providerUrl.getParameter(GENERIC_KEY))) {
                Class interfaceClass = Class.forName(interfaceName);
                ServiceDefinition serviceDefinition = ServiceDefinitionBuilder.build(interfaceClass);
                Gson gson = new Gson();
                String data = gson.toJson(serviceDefinition);
                serviceDefinitions.put(providerUrl.getServiceKey(), data);
                return;
            }
            logger.error("publishProvider interfaceName is empty . providerUrl: " + providerUrl.toFullString());
        } catch (ClassNotFoundException e) {
            //ignore error
            logger.error("publishProvider getServiceDescriptor error. providerUrl: " + providerUrl.toFullString(), e);
        }
    }

public static boolean isGeneric(String generic) {
        return StringUtils.isNotEmpty(generic)
                && (GENERIC_SERIALIZATION_DEFAULT.equalsIgnoreCase(generic)  /* Normal generalization cal */
                || GENERIC_SERIALIZATION_NATIVE_JAVA.equalsIgnoreCase(generic) /* Streaming generalization call supporting jdk serialization */
                || GENERIC_SERIALIZATION_BEAN.equalsIgnoreCase(generic)
                || GENERIC_SERIALIZATION_PROTOBUF.equalsIgnoreCase(generic)
                || GENERIC_RAW_RETURN.equalsIgnoreCase(generic));

    }

How to eliminate this error?