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Interface Layer

Web Servers Clients and applications use the interface layer to communicate withContent Server and interact with the content repository. The interface layer consists ofDocumentum Foundation Classes (DFC) and a number of standard interfaces built on topof DFC.
Documentum Foundation Classes
Documentum Foundation Classes (DFC) represents the richest API exposing allDocumentum functionality. DFC provides an object-oriented framework for accessingthe capabilities of Content Server DFC exposes the Documentum object model as anobject-oriented client library for content management applications to use. It is an API thatcan be used from a host of applications, including those developed in Java, Visual Basic,C#, and C++. DFC is implemented as a set of Java classes and interfaces, along with aJava-COM bridge for accessing DFC via COM from Visual Basic or Visual C++.
Everycomputer running an application that accesses Content Server has a copy of the DFCsoftware running on a Java Virtual Machine (JVM). The application on the client machineperforms a method call through DFC, which translates the call into the Content server’snative API. Content Server instantiates the object, executes the method call, and returnsthe result to the client application.
Applications access Content Server through DFC using a client object. Creating a clientobject loads the necessary shared libraries. The client object interface then serves as afactory for session objects, which represent connections to the repository. The applicationcreates new repository objects or obtains references to existing objects through thesession interface
Documentum Business Objects
Documentum also provides a way to extend DFC using the Documentum BusinessObjects Framework (BOF). Documentum Business Objects Framework provides aframework and a methodology to develop reusable business logic components calledBusiness Objects. This framework is built into DFC and accessible from applicationswritten using DFC. It is designed to provide the ability to develop pluggable components,each component implementing one or more middle-tier business rules. BOF canimplement business logic in reusable business object components that can be pluggedinto middle tier or client applications. BOF enables programmers to develop highlyreusable components that can be shared by multiple applications.
There are two types of Documentum Business Objects, type-based business objects andService-based business objects.
A type-based business object can extend a Content Serverpersistent object type and extend its capabilities by providing new methods for thosetypes and allow overriding of existing methods. A type based business object enablesdevelopers to define type-specific behavior without the need to customize each clienttype the same business object can be used with WebTop or Desktop-based applications.
A service based business object provides methods that perform more generalizedprocedures that are not usually bound to a specific object type or repository.At any level, a method of a business object can be called by other DFC-basedapplications. JSP, ASP, Visual Basic, and other languages all have access to the businessobjects.
Web Services
DFC and BOF enable developers to encapsulate custom business logic that can beexposed as Web service. They provide a way to call functions on other computers acrossthe intranet or World Wide Web. For example, a CRM system can communicate withDocumentum through Web service. For Documentum customers, this means broader,industry standard access to content management functionality.
Developers can create their own service on Documentum platform. Developers work with theirpreferred development environments, toolkits, and application servers to develop Webservices over the Documentum API. Web services can be deployed on a Web server,where they are available to any networked client a desktop application, a Web applicationor portal, or even another Web service or remote client/system.

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