[23/07/19 05:30:24:024 CST] main ERROR integration.MetadataReportService:  [DUBBO] publishProvider getServiceDescriptor error. providerUrl: dubbo://30.5.121.125:20880/org.apache.dubbo.samples.generic.call.api.HelloService?anyhost=true&application=generic-impl-provider&deprecated=false&dubbo=2.0.2&dynamic=true&generic=true&interface=org.apache.dubbo.samples.generic.call.api.HelloService&methods=*&register=true&release=2.7.3&side=provider, dubbo version: 2.7.3, current host: 30.5.121.125
java.lang.ClassNotFoundException: org.apache.dubbo.samples.generic.call.api.HelloService
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:264)
	at org.apache.dubbo.metadata.integration.MetadataReportService.publishProvider(MetadataReportService.java:97)
	at org.apache.dubbo.config.ServiceConfig.doExportUrlsFor1Protocol(ServiceConfig.java:623)
	at org.apache.dubbo.config.ServiceConfig.doExportUrls(ServiceConfig.java:457)
	at org.apache.dubbo.config.ServiceConfig.doExport(ServiceConfig.java:415)
	at org.apache.dubbo.config.ServiceConfig.export(ServiceConfig.java:378)
	at org.apache.dubbo.samples.generic.call.GenericImplProvider.main(GenericImplProvider.java:48)

Reproduce by running dubbo-samples-generic-impl
Assertions.assertTrue(metadataReportService1.metadataReport instanceof JTestMetadataReport4Test);
        JTestMetadataReport4Test jTestMetadataReport4Test = (JTestMetadataReport4Test) metadataReportService1.metadataReport;
        Assertions.assertTrue(jTestMetadataReport4Test.store.containsKey(JTestMetadataReport4Test.getProviderKey(publishUrl)));
        String value = jTestMetadataReport4Test.store.get(JTestMetadataReport4Test.getProviderKey(publishUrl));
        FullServiceDefinition fullServiceDefinition = toServiceDefinition(value);
        Map<String,String> map = fullServiceDefinition.getParameters();
        Assertions.assertEquals(map.get("application"), "vicpubp");
        Assertions.assertEquals(map.get("version"), "1.0.3");
        Assertions.assertEquals(map.get("interface"), "org.apache.dubbo.metadata.integration.InterfaceNameTestService");
    }
    @Test
    public void testPublishConsumer() throws InterruptedException {
        URL publishUrl = URL.valueOf("dubbo://" + NetUtils.getLocalAddress().getHostName() + ":4444/org.apache.dubbo.TestService?version=1.0.x&application=vicpubconsumer&side=consumer");
        metadataReportService1.publishConsumer(publishUrl);
        Thread.sleep(300);
        Assertions.assertTrue(metadataReportService1.metadataReport instanceof JTestMetadataReport4Test);
        JTestMetadataReport4Test jTestMetadataReport4Test = (JTestMetadataReport4Test) metadataReportService1.metadataReport;
        Assertions.assertTrue(jTestMetadataReport4Test.store.containsKey(JTestMetadataReport4Test.getConsumerKey(publishUrl)));
        String value = jTestMetadataReport4Test.store.get(JTestMetadataReport4Test.getConsumerKey(publishUrl));
        Gson gson = new Gson();
        Map<String, String> map = gson.fromJson(value, Map.class);
        Assertions.assertEquals(map.get("application"), "vicpubconsumer");
        Assertions.assertEquals(map.get("version"), "1.0.x");
    }
    private FullServiceDefinition toServiceDefinition(String urlQuery) {
        Gson gson = new Gson();
        return gson.fromJson(urlQuery, FullServiceDefinition.class);
    }
}