The Component Object Model (COM) is an object-oriented architecture for creating objects that can be reused from application to application. You can also use it to write objects that can be accessed from other programming environments such as Microsoft Visual Basic and Microsoft Visual C++, as well as applications such as Microsoft Office. COM provides a standard protocol for connecting objects together, even if they are designed in different programming languages. When a connection has been made, the objects communicate through a standard interface.
Visual J++ provides support for building and importing COM objects. By building COM objects in Visual J++, you can provide reusable components that can be shared by any number of applications as well as applications written in different languages. The COM import features allow you to use objects from other applications to provide additional features in your Windows Foundation Classes for Java (WFC) applications. For example, you can use the COM objects that Microsoft Office exposes to access spell checking features in Microsoft Word or mathematical functions in Microsoft Excel. By using COM in your Visual J++ projects, you provide true code reuse in your application development.
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