COM+ Technical Series: Series Guide

COM+ Technical Series Overview

Microsoft Corporation

September 1999

Summary: Brief overview and background for the COM+ Technical series of articles. (4 printed pages)

Overview

In preparation for the upcoming Microsoft® Windows® 2000 release, we’ll be delving deeper into the Component Object Model (COM) by detailing specific application scenarios to better enable you to utilize COM+ Services 1.0 in Visual Studio® 6.0, which will enable you to use Windows 2000 more productively. In this series of articles, we’ll provide details on specific COM+ scenarios with a variety of code snippets so you can begin working with COM+ Services 1.0 and Visual Studio 6.0 today.

Why COM+ for Windows 2000?

Integrated into Windows 2000, COM+ Services 1.0 extends the Component Object Model to simplify the creation and use of software components, while improving application scalability and increasing flexibility. COM+ Services 1.0 provides a run time and services that are readily used from any tool in Visual Studio, and enables extensive interoperability between components, regardless of the tool used to implement them.

In this series of articles, we’ll describe the following COM+ Services in version 1.0 and give you the tools necessary to get a jumpstart on COM+ development for Windows 2000 using Visual Studio 6.0. Technical Series topics include:

• Object Pooling (Scenario #1 of 3)
  
  
• Loosely Coupled Events (Scenario #2 of 3)
  
  
• Queued Components (Scenario #3 of 3)

COM+ Services 1.0 also has additional features that expedite component development and deployment, such as simplified creation of server components, full transactional capabilities, role-based security, and centralized administration. But what happened to In-Memory Database?

Why Visual Studio 6.0?

The Microsoft Visual Studio 6.0 development system is a comprehensive suite of industry-leading development tools for building business applications for Windows 2000 Server, including client/server, multitier, and Web-based solutions. Visual Studio 6.0 includes key enterprise and team development features designed to help developers rapidly build scalable distributed applications that can be easily integrated with existing enterprise systems and applications.

COM+ Background

Building on a Successful Base

COM+ builds on the proven success of COM.

• COM is in use on 200 million systems worldwide.
  
  
• COM supports a vibrant component marketplace. The demand for third-party components based on COM has been estimated to be $410 million this year, with a projected 65 percent compound annual growth rate, and it is expected to grow to approximately $3 billion by 2001 (source: Giga Information Group). This base of available components allows developers to choose from a wide variety of components to assemble applications and solutions, which has revolutionized development on Windows platforms.
  
  
• COM supports thousands of available applications, including the highest-volume applications in the industry.
  
  
• Major system vendors, such as Hewlett-Packard Co., Digital Equipment Corp., and Siemens Nixdorf Information Systems Inc., have announced plans to ship COM on UNIX and non-UNIX systems within the year, and additional vendor commitments are expected to follow. In addition, Software AG has ported COM to many operating systems, including Solaris and MVS.
  
  
• COM consists of a well-defined, mature, and stable specification, as well as a reference implementation, which has been widely tested and adopted worldwide as a de facto standard. For more on the COM specification, see the COM Web site, located at www.microsoft.com/com/.
  
  
• COM is supported by the largest number of development tools available for any component or object model on the market.
  
  
• COM+ enables the creation of the next generation of component-based applications, making it even easier to build and use components and providing richer, extensible services.

New Features in COM+

COM+ is an evolutionary extension to the Component Object Model (COM), the most widely used component technology in the world. COM+ makes it even easier for developers to create software components in any language, using any development tool. COM+ builds on the same factors that have made today’s COM the choice of developers worldwide, including the following:

• The richest integrated services, including transactions, security, message queuing, and database access, to support the broadest range of application scenarios.
  
  
• The widest choice of tools from multiple vendors using multiple development languages.
  
  
• The largest customer base for customizable applications and reusable components.
  
  
• Proven interoperability with users’ and developers’ existing investments.

COM provides the component technology for Microsoft Windows Distributed interNet Applications (Windows DNA) architecture, which enables developers to integrate Web-based and client/server applications in a single, unified architecture. Using COM, developers can create distributed components that are written in any language and that can interact over any network. COM also provides interoperability with components on other platforms, such as Solaris, HP-UX, DEC UNIX, and Siemens Nixdorf SINIX.

COM+ expands Microsoft’s lead in component and object technology by making it easier to build and use components in any language, as well as providing new, innovative services for developers. Delivered on the Windows platform, COM+ is designed to preserve and extend customers’ current investments in COM. Applications currently using COM technology will work in the COM+ environment. In addition, developers may choose to take advantage of the ease of use and rich new optional services that COM+ provides in key areas such as database access.

COM+ builds on the experience gained from the development and use of COM and associated products and technologies, such as Microsoft Transaction Server and Microsoft developer tools, and it incorporates feedback from thousands of developers around the world.