Polish : spring-cloud-incubator/spring-cloud-alibaba#478 : Dubbo Service registration issue on Zookeeper Registry

spring-cloud-alibaba-dubbo/src/main/java/org/springframework/cloud/alibaba/dubbo/registry/apache/zookeeper/ZookeeperRegistrationFactory.java

@@ -44,6 +44,9 @@ public class ZookeeperRegistrationFactory extends AbstractRegistrationFactory<Zo
                 .port(serviceInstance.getPort())
                 .build();
 
+        // To trigger build() method
+        registration.getServiceInstance();
+
         return registration;
     }
 }