public String getUniqueKey(KeyTypeEnum keyType) {
        return super.getUniqueKey(keyType, application);
    }
@Test
    void testGetUniqueKey() {
        String interfaceName = "org.apache.dubbo.metadata.integration.InterfaceNameTestService";
        String version = "1.0.0.zk.md";
        String group = null;
        String application = "vic.zk.md";
        MetadataIdentifier providerMetadataIdentifier =
                new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE, application);
        Assertions.assertEquals(
                providerMetadataIdentifier.getUniqueKey(KeyTypeEnum.PATH),
                "metadata" + PATH_SEPARATOR + interfaceName + PATH_SEPARATOR
                        + (version == null ? "" : (version + PATH_SEPARATOR))
                        + (group == null ? "" : (group + PATH_SEPARATOR)) + PROVIDER_SIDE
                        + PATH_SEPARATOR + application);
        Assertions.assertEquals(
                providerMetadataIdentifier.getUniqueKey(KeyTypeEnum.UNIQUE_KEY),
                interfaceName
                        + MetadataConstants.KEY_SEPARATOR
                        + (version == null ? "" : version)
                        + MetadataConstants.KEY_SEPARATOR
                        + (group == null ? "" : group)
                        + MetadataConstants.KEY_SEPARATOR
                        + PROVIDER_SIDE
                        + MetadataConstants.KEY_SEPARATOR
                        + application);
    }