Echelon OpenLNS - Manual (Page 39)

OpenLNS Programmer's Reference 2
Introduction
The OpenLNS Object Server ActiveX Control provides high-level services for installing,
diagnosing, maintaining, and monitoring and controlling L ON W ORKS networks. This
ActiveX control is an OpenLNS client application interface into the OpenLNS network
operating system. The OpenLNS network operating system allows L ON W ORKS network
tools to interoperate with one another, and interact with the managed L
ON
W
ORKS
network. OpenLNS brings the power of client-server architecture, and object-oriented,
component-based software design into control networks. This enables OpenLNS tools to
work together to install, maintain, monitor, and control L
ON
W
ORKS
networks. In
addition, it provides the fastest, most efficient way to bring control on-line with all your
other information systems.
The OpenLNS Object Server provides its services through a set of objects which
correspond to components within a L ON W ORKS network. These objects are therefore
referred to as L
ON
W
ORKS
Component Architecture (LCA) objects. The classes which
define the LCA objects are organized into the OpenLNS Object Hierarchy. The
LcaObjectServer class is the highest level (root) class within this hierarchy. The root
class contains lower level objects, and the lower level objects contain additional objects,
creating a tree structure.
An object is "contained" by a higher level, or parent, object when it may be accessed
through a property of the parent. Some properties return individual objects, while
others contain a collection of objects. Lower level objects may appear in several locations
within the class tree. For example, Interface objects are contained by both
DeviceTemplate and AppDevice object s. See the OpenLNS Object Server Object Model
for more information.
OpenLNS Object Server Object Model
This section gives an overview of the object model depicted in the OpenLNS Object
Hierarchy. The "Lca" prefixes have been eliminated from the names for this discussion
for reasons discussed in Object Naming Convention.
The ObjectServer class is the highest level (root) class within this hierarchy. An instance
of this class can be created directly by an OpenLNS application. Typically, in
development tools such as Visual C# .NET, Visual C++ .NET, and Visual Basic .NET,
this is done by dragging a representation of the control from a palette onto a form or
workspace. This creates an ObjectServer object, which represents an instance of the
OpenLNS ActiveX control.
Many objects include properties that reference other objects or collections of objects. For
example, an AppDevice object contains a DeviceTemplate object which references the
device template which was used to create the application device that the AppDevice
object represents. These object references define a tree structure for the Object Server.
The ObjectServer object directly references six collection objects: the ComponentApps
class (in the ObjectServer object's ComponentApps property), the NetworkInterfaces class
(in the NetworkInterfaces property), three instances of the Networks class (in the
Networks, RemoteNetworks, and VNINetworks properties), and the Extensions class (in
the Extensions property). These objects represent the component applications, network
interfaces, extensions, and networks which have been registered on the computer or are
otherwise available for use by the Object Server.