code: public static xen[] reboot(nitro_service client, xen[] resources) throws Exception
  	{
  		if(resources == null)
  			throw new Exception("Null resource array");
  		
  		if(resources.length == 1)
  			return ((xen[]) resources[0].perform_operation(client, "reboot"));
  		
  		return ((xen[]) perform_operation_bulk_request(client, resources, "reboot"));
  	}
docs: <pre>
  Use this operation to reboot XenServer in bulk.
  </pre>