Role of OMD [reprinted]

Role of OMD [reprinted]

1. Role of OMD
OMD (Object Model diagram) is based on the representation of OMT (Object Modeling Technique). Let's take a look at what OMD can do for us?
1. What interfaces does this class support;
2. What objects are required to complete the task;
3. How to Use objects of this class;
4. Can classes be directly instantiated;
5. Methods and attributes of interfaces;
6. Whether other classes support this interface;
7. Relationship between objects

2. OMD symbolic explanation
There are three classes in OMD: abstract class, component class, and common class.
(Class ). The main purpose of an abstract class is to define a public interface for its subclass. An abstract class will delay some or all of its implementations to the subclass. Therefore, an abstract class cannot be instantiated. I
Component class objects can be directly created. Although common class objects cannot be directly created, they can be created as an attribute of other classes or instantiated from other classes. AO
Dataset or geometry in
Classes is an example of an abstract class. A geometry object cannot be created, but a polyline can be created. This polyl
The INE object actually implements the interface defined in geometry on the basis of the class, so the interface defined in the base class object can be accessed from the coclass.
In OMD
Link types mainly include type inheritance (Type
Inheritance, instantiation, composition, and Associati
ONS. We mentioned in the com chapter that the inheritance actually completely inherits the superclass interface, which can be clearly viewed using the AO Object Browser tool.
And the composition relationship refers to the primary-secondary relationship between objects. That is to say, the existence of the subject's life determines whether the Sub-body exists.

3. Ao Organization Division
ESRI divides the entire AO structure and finds the corresponding OMD in pdf format according to different application fields. From the help of AO development, we can find the following subsystems:
1. 3D Analyst extension-component objects used for 3D visualization and surface modeling;
2. Application Framework --- allows developers to customize user interfaces In ArcMap and arccatalong;
3. arccatalog --- allows developers to expand the data object model and integrate custom objects and views into the arccatalog application framework ;.
4. ArcMap --- provides core functions of the ArcMap application for operations and display of map documents;
5. ArcMap editor --- includes the extension Component Object of the object editor. You need to edit and develop it;
6. an important application of display --- GIS is data performance, which is especially popular for many end users in China, the objects contained here can be used to complete functions such as Map Symbol display, graphic editing feedback track, coordinate transformation, and screen control;
7. geocoding --- mainly used to create and manage geocoding services;
8. geodatabase --- AO development is indispensable. After all, GIS applications focus on data, therefore, the related GIS Data creation, loading, management, and storage are all implemented through the object here;
9. Geometry --- whether it is a element or a graph, it involves the acquisition and application of spatial information;
10. IMS --- provides the ability to connect to the ArcIMS server and access ArcIMS images and element services;
11. Network --- provides network creation, management, and analysis operations. You plan to customize and develop network objects that can be used by specific network applications;
12. Output --- there is output when there is input. If you want to output the prepared map, use the object provided here to complete it;
13. Raster --- AO object used to access and manage raster data;
14. Spatial Reference --- used to complete the space reference settings;
15. streetmap USA extension --- this has little to do with domestic users.