Garry Froehlich

Hooking into object-oriented application frameworks

An object-oriented application framework provides a generic design within a given domain and a reusable implementation of that design. Frameworks have great potential for reuse, but that potential can only be achieved if the framework can be understood and used effectively by application developers. The complexity of the design and implementation of a framework can make understanding the framework difficult, and so good documentation and guidance to the framework user is needed. Several methods exist for documenting the design of the framework, but less work has been done on documenting the purpose of the framework and how it is intended to be used. In this paper, we introduce the concept of hooks as a means of documenting and providing guidance on the intended use of a framework. Each hook provides a concise solution to a focused requirement or problem within the context of the framework. Solutions for more complex requirements can be provided by combining several hooks. A discussion and means of describing hooks is given, with a focus on the method of adaption used to fulfill the requirement and the level of support provided for the solution within the framework.

Application framework issues when evolving business applications for electronic commerce

When an organization embarks on e-commerce it rarely has a chance to re-engineer its existing business applications. However, if these business applications were built using an application framework, then one might hope to reuse many of the existing legacy applications in the new e-commerce context. This paper examines the general issues created by migrating applications to e-commerce, and proposes an architecture for application frameworks that must support e-commerce.

Choosing an object-oriented domain framework

Object-oriented frameworks [2] enable developers to rapidly produce new applications — provided that the framework is actually suited to the requirements of the new application. Often, previous experience with the framework is used to make this decision, but when application developers are unfamiliar with a new framework they have no experience for deciding whether or not to use it. They may not discover that a framework lacks support for key requirements of an application until well into the development cycle, resulting in substantial redevelopment or discarding of the project altogether. They require a basis for making the initial decision of whether or not to invest time in understanding and using the framework. Our approach is most successful for domain specific object-oriented frameworks. Due to their size and overall generality, this approach may not be as applicable to enterprise frameworks. We have been working with existing frameworks such as HotDraw [6], as well as developing new frameworks in the engineering domain (EAF). Our experience, common to most framework users, is that building up the level of expertise necessary to know in detail what applications a framework can be used for is a time consuming process due to the abstract nature and complexity of most frameworks. How can this expertise be captured and be made available to new users of the framework to help them decide whether or not to use the framework? In other words, how do we describe the applicable domain of the framework? A new application can fall into one of three areas. It can be (1) clearly outside

Providing support for process model enaction in the Metaview metasystem

Process modeling is a means of formally defining many aspects of the software development process through the use of models. Partial automation of a process model can help to improve the software process. Menial or tedious tasks, such as collecting metrics, no longer have to be the responsibility of the developer. Coordination of effort can also be enhanced through automation. Automation can be achieved through the development of a process modeling support environment and the appropriate CASE tools. This is one of the major goals of the Metaview project, which involves the design and development of a metasystem to generate such an environment. A key requirement for this type of support environment is to use an active database. Active databases can react through an action to events, such as changes to a particular data item, thereby giving them the flexibility needed for process modeling. The paper presents an execution model for the support of process model enaction in the Metaview system. The execution model is intended to support a wide variety of process models and process modeling languages. The model is based upon the event rule model used in active databases.<<ETX>>

Developing engineered product support applications

Product line developers have two primary problems to solve: keeping their applications relevant to the associated manufactured product line, and evolving their applications to exploit new information technologies. This paper reports on our experience in developing commercial applications for engineered product manufacturers. High quality object-oriented frameworks with good factoring into services are crucial to addressing both of these issues. We have also learned that it is not sufficient to develop frameworks that address only the development of the application. They must also support other parts of the process: from production of documentation, through help desk integration, to defect tracking and resolution. This work also contains a catalog of best practices and advanced features that we believe will be valuable to other builders of engineering tools.

Exploring O-O framework usage (poster session)

Object-oriented application frameworks are becoming an increasingly popular part of software development but there has been little work on studying how they are actually used. An object-oriented application framework comprises a design and an object-oriented implementation of that design meant to apply to a broad range of applications, or subsystems within a single domain, such as graphical user interfaces. FrameScan is an ongoing study with the goal of understanding how developers can effectively and efficiently understand and deploy framework technology to construct and evolve their applications. In order to study how frameworks are used, 34 students of a senior year software engineering course were divided up into six teams of five or six students each. Each team had three months to design and implement a small client-server application of their choosing with the requirement that a framework for client-server computing called CSF (Client-Server Framework) be used as part of the project. The conclusions of the study are presented.