type serviceInstancesStore struct {
	ip2instance map[string][]*model.ServiceInstance
	// service instances by hostname -> config
	instances map[instancesKey]map[configKeyWithParent][]*model.ServiceInstance
	// instances only for serviceentry
	instancesBySE map[types.NamespacedName]map[configKey][]*model.ServiceInstance
	// instancesByHostAndPort tells whether the host has instances.

	store := serviceInstancesStore{
		ip2instance:            map[string][]*model.ServiceInstance{},
		instances:              map[instancesKey]map[configKeyWithParent][]*model.ServiceInstance{},
		instancesBySE:          map[types.NamespacedName]map[configKey][]*model.ServiceInstance{},
		instancesByHostAndPort: sets.Set[hostPort]{},
	}
	instances := []*model.ServiceInstance{

		}
		inconsistents, errors := findInconsistencies(clusterServices)
		if len(inconsistents) > 0 {
			var serviceInstance *resource.Instance
			for _, r := range clusterServices {
				if r != nil {
					serviceInstance = r
					break
				}
			}
			message := msg.NewMultiClusterInconsistentService(serviceInstance, fullname.Name.String(),
				fullname.Namespace.String(), inconsistents, errors)

			c.Report(gvk.Service, message)

     * @param serviceType The type to make this service visible as.
     * @param serviceInstance The service implementation.
     */
    <T> void add(Class<T> serviceType, T serviceInstance);

    /**

				fmt.Errorf("invalid service port value %d for %q: %v", port.Port, port.Name, err))
		}
	}
	return errs
}

// Validate ensures that the service instance is well-defined
func (instance *ServiceInstance) Validate() error {
	var errs error
	if instance.Service == nil {
		errs = multierror.Append(errs, fmt.Errorf("missing service in the instance"))
	} else if err := instance.Service.Validate(); err != nil {