COM+ is a part of the Windows operating system that provides various infrastructure-level services to interested applications. These services include automatic transaction management, object pooling, just-in-time activation, queued components, and so on.
.NET components that make use of COM+ component services are called serviced components. This exam objective tests your skills on creating and consuming serviced components. Although not explicitly mentioned in the objective list, you should be ready to answer questions on specific COM+ services because the reason for the existence of a serviced component is mainly to use these services.
To use COM+ services, a serviced component must be registered with COM+. One of the requirements for the registration is that the assembly that contains the serviced component must be signed with a strong name. A strong name uniquely identifies the components in an assembly and avoids any identity clash with other components.
One of the preferred places to deploy a component that uses COM+ services is the global assembly cache (GAC). The exam objective also requires you to know the process of deploying a component to the GAC.
Windows provides a Component Services administrative tool. System administrators can use this tool to configure the serviced components at runtime. However, a serviced component's methods are not visible to this tool unless the component exposes the required interfaces. The exam objectives require you to know how to expose these interfaces and how to configure a component with the Component Services administrative tool.
Introduction
Evolution of Component Services
Component Object Model (COM)
Microsoft Transaction Server (MTS)
COM+ 1.0 and COM+ 1.5
COM+ 2.0 (The .NET Framework)
Exposing .NET Components to COM/COM+
Calling a .NET Component from COM/COM+
Exporting .NET Components As COM Type Libraries
Architecture of Component Services
Serviced Components
Declarative Programming Model
COM+ Applications
COM+ Catalog
Serviced Component Activation
Context
Interception
Creating and Consuming a Serviced Component
Creating a Serviced Component
Creating a Strongly Named Assembly
Registering the Serviced Component into the COM+ Catalog
Using the Component Services Administrative Tool to Manage Components
Creating Interfaces That Are Visible to COM/COM+
The ClassInterface Attribute
Versioning Problems and the ClassInterface Attribute
The InterfaceType Attribute
Component Identification
Installing the Component in the Global Assembly Cache
Component Versioning
Consuming a Serviced Component
Understanding and Using Enterprise Services
Object Pooling
Configuring a Serviced Component to Use the Object Pooling Service
How Object Pooling Works
Creating an Object-Pooled Serviced Component
Using an Object-Pooled Serviced Component
Monitoring Statistics of a Serviced Component
Just-In-Time Activation
How Just-in-Time Activation Works
Using Just-in-Time Activation with Object Pooling—A Recipe for High Throughput
Design Considerations for Using Just-in-Time Activation and Object Pooling
Creating a JIT-Activated Object-Pooled Serviced Component
Using a JIT-Activated Object-Pooled Serviced Component
Object Construction
Automatic Transaction Processing
Using Automatic Transaction Service for Local Transactions
Elements of Transaction Processing
How Automatic Transaction Works
Using Automatic Transaction Service for Distributed Transactions
Queued Components
How Queued Components Work
Creating a Queued Component
Creating a Client for a Queued Component
Chapter Summary
Apply Your Knowledge
