R. Lajoie and R. Keller, "Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts and Motifs in Concert," in Object-Oriented Technology for Database and Software Systems, V. Alagar and R. Missaoui, Eds. Singapore: World Scientific Publishing, 1995, pp. 295-312.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....major redesigns in the future by ensuring that a framework can change in specific and predefined ways. Besides these benefits, the information conveyed within a design pattern description can also be used to document the design of a framework and communicate it to other developers [BJ94, Joh92, LK94, MDE97] This will be shown in Chapter 3. 2.2.3 Design Pattern Pitfalls Obviously, design patterns not only o#er advantages, but also exhibit some important disadvantages . Design pattern can complicate the design. Design patterns achieve flexibility by introducing extra abstractions and ....

....a framework. Catalog patterns document a framework s application domain, main features and scope, whereas application patterns corresponds to Johnsons notion of patterns to document a framework, and design patterns provide detailed information about the design of the framework. Similarly, LK94] also uses Johnsons patterns (which are termed motifs in their approach) in combination with design patterns and formal contracts [HHG90] Again, the emphasis of this approach is on documenting how to use a framework. OQC97] promotes the principle of documenting by designing by using design ....

Richard Lajoie and Rudolf K. Keller. Design and reuse in object-oriented frameworks: Patterns, contracts and motifs in concert. In Proc. of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences (ACFAS), pages 94--105, 1994.

....object oriented paradigm An object oriented system is a collection of encapsulated objects that collaborate among themselves to achieve specified tasks. The benefits of systems designed using OO principles include the potential for reuse, incremental extension and local modification. According to [30] and others, one can distinguish several levels of reuse. At the lowest level, one reuses methods or classes. This form of reuse is often inadequate since methods and classes are not islands . They cannot be reused independently. At the highest level, one reuses entire application frameworks. ....

R. Lajoie and R. Keller. Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. In V. Alagar and R. Missoui, editors, Object-Oriented Technology for Database and Software Systems. World Scientific Publishing Co. Pte. Ltd, 1995.

....Benefits and drawbacks of applying the pattern are also discussed. 2.3. Electronic document based mixed techniques Several works have proposed combinations of two or more of the described techniques, using hypertext to link the different documentation components. For example, Lajoie and Keller [13] extended Johnson s textual patterns, introducing the term motif to name these patterns, in order to avoid confusion with design patterns. They use a template for a motif description that has a name and intent, a description of the reuse situation, the steps involved in customization, and cross ....

Lajoie R., Keller R. Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. Proceedings of the 62 nd Congress of the ACFAS, Canada, May 1994.

....access to member variables with a more abstract interface. 6 The refactoring technique was used to build some existing frameworks. 3. 2 Lajoie s Method Lajoie proposed an approach to representing and documenting micro architectures and frameworks using design patterns, contracts, and motifs [11]. He identified three different levels of reuse and abstraction in frameworks: ffl reuse in the small; ffl reuse in the medium: micro architecture reuse and the reuse of systems architectures, i.e. framework applications; ffl reuse in the large. Along with design patterns, Lajoie proposes two ....

R. Lajoie and R. K. Keller, "Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert," in Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences (ACFAS), (Montreal, Canada), May 1994. 10

....We discuss the various styles of documentation that have been used to describe frameworks. The ET framework comes with example applications, a cookbook, and a reference manual, and the PhD theses of Gamma and Weinand discuss the architectural rationale using design patterns. Lajoie and Keller [LK95] adopt an approach that combines recipes, design patterns, and contracts, all cross referenced to document the ET framework. Example Application The source code of example applications that have been constructed using the framework is often the first and only documentation provided to ....

....The organization follows a spiral approach where recipes for the most frequent forms of reuse are presented early, and where concepts and details are delayed as long as possible. The first recipe is an overview of the framework concepts and the other recipes. Butler 3 Motif Lajoie and Keller [LK95] introduce the term motif for Johnson s patterns in order to avoid confusion with design patterns. They use a template for a motif description that has a name and intent, a description of the reuse situation, the steps involved in customization, and cross references to motifs, design patterns, and ....

Richard Lajoie and Rudolf K. Keller, Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert, Object-Oriented Technology for Database and Software Systems, V.S. Alagar and R. Missaoui (eds), World Scientific Publishing, Singapore, 1995, pp. 295--312.

....and Ericsson context and contains excellent suggestions also suitable for the interviewed companies. Several approaches to documenting reusable assets have been proposed and studied. The ET framework is documented using example applications, a cookbook and a reference manual [Lewis et al. 95] Lajoie Keller 95] discuss an approach using cross referenced recipes, design patterns, and contracts. Mattsson 96] classifies documentation of object oriented frameworks into approaches using cookbooks, design patterns or a framework description language. Despite all the research on documentation, it remains a ....

. Richard Lajoie and Rudolf K. Keller, `Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert,' Object-Oriented Technology for Database and Software Systems, V.S. Alagar and R. Missaoui (eds), World Scientific Publishing, Singapore, 1995, pp. 295-312.

....this benefits, with object oriented frameworks, reuse of software won t remain a cut and paste of fractions of code, moreover reuse will become a methodical approach. 2. 3 Use and Reuse of Frameworks In general, the levels of reuse can be identified in four different layers of abstraction [9, 10], figure 2) Figure 2 : Different levels of reuse and abstraction 5 The reuse in the small involves low level reuse, i.e. the reuse of classes, methods and fractions of code. Reuse of micro architectures provides reuse in the terms of behaviour of collaborations of objects. These level ....

R. Lajoie, R. K. Keller, Design and Reuse in Object-Oriented Frameworks : Patterns, Contracts and Motifs in Concert, Proceedings of the 62nd Congress of ACFAS, Montreal, Canada, May 1994.

....concept is discussed further, together with a categorisation of composability constraints. A small framework example is given in the fourth section. Fig. 1 Framework based application 1. 1 Definitions Frameworks have been discussed in more detail by several other researchers [2] 3] 4] [5] and [6] This paper uses the following definitions based on a simple model of generating an application based on one or more frameworks. The application engineer designs application classes, which are either new increment classes, or subclasses from the frameworks or classes composed by framework ....

Lajoie, R., Keller, R. K., "Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts and Motifs in Concert", Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences, pp. 94-105, Montreal, Canada, May 1994. Page 6

....the pattern. 4) Consequences Analysis to present the results and trade offs of applying the pattern. Typically this information is provided in a template, though some aspects of Contracts [36] for documenting frameworks actually document patterns: the connection is elaborated in work of Lajoie [47, 48]. The standard way to document a design pattern is the template [29, p.6] shown in Figure 3. A template provides a consistent format for documentation which makes design patterns easier to learn, compare and use. Design patterns vary in their granularity and level of abstraction, as well as in ....

Richard Lajoie and Rudolf K. Keller, Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert, Colloquium on Object-Orientation in Databases and Software Engineering, 62nd Congress of ACFAS, Montreal, May 16--17, 1994.

....basis of the framework and examples of its use [9] or can be a listing of individual problems and their step by step solutions within the framework [12] Similarly, framework patterns [8] document common problems and solutions with examples through a general narrative. These are called motifs in [10]. The information contained in cook books and framework patterns is valuable but cannot be easily interpreted by an automated tool, unlike hooks. A tool for the exploration and use of frameworks through exemplars is described in [6] A concrete instance is provided for all abstract classes in the ....

R. Lajoie and R. K. Keller. Design and Reuse in Object Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. In Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences, Montreal, Canada, 1994.

....relied on several books [1, 5, 12, 16] and articles describing frameworks, as well as those papers dealing specifically with documentation of frameworks. Of particular note are the discussion in Chapter 3 of Pree s book [16] the synthesis of contracts, patterns, and motifs by Lajoie and Keller [11]; and our attempts to reuse the ET [12] and MET frameworks [1] where the documentation consists of examples, man pages for classes, and a cookbook accessible as hypertext. Kinds of Framework Reuse It is important to realize that the styles of documentation for frameworks discussed in the ....

....occurs repeatedly in the problem domain of the framework, and also describes how to solve that problem. Each pattern possesses the same format. The elements of a pattern are: description of its purposes, explanation of how to use it, description of its design, and some examples. Lajoie and Keller [11] introduce the term motif for Johnson s patterns in order to avoid confusion with design patterns. They use a template for a motif description that has a name and intent, a description of the reuse situation, the steps involved in customization, and cross references to motifs, design patterns, ....

[Article contains additional citation context not shown here]

Lajoie, R. and Keller, R.K. Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert. In Object-Oriented Technology for Database and Software Systems. V.S. Alagar and R. Missaoui (eds). World Scientific Publishing, Singapore, 1995, pp. 295--312.

....a thread of execution which mostly is buried under framework code. One solution approach, based on the design by contract ideas, is to exactly define the interface between the framework and the increment as pre and post conditions or behavioural interaction constraints [Meyer 92, Helm et al. 90, Lajoie Keller 94] Precondition violation causes exceptions to be raised and it can be guaranteed that the framework will never crash as a result of illegal use. 4.3 Framework Composition Traditionally, object oriented framework based development of applications takes the approach that the application ....

. R. Lajoie, R.K. Keller, Design and Reuse in Object-oriented Frameworks: Patterns, Contracts and Motifs in Concert, Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences, Montreal, Canada, May 1994. 18

.... Riehle and Z llighoven [90] Adams [91] x Problem x Solution x Purpose x Problem x Context x Solution x Compare x Aliases x History x Preconditions x Problems x Constraints x Solution Table 7 Alternative Design Pattern Documentation Formats Rubel [92] Lajoie and Keller [93] Gamma et al. Gang of Four ) 94] x Problem x Context x Forces x Solution x Resulting Context x Design Rationale x Related Patterns x Rationale Intent x Category x Motivating Example x Applicability x Description x Diagram x Discussion x Implementation x ....

R. Lajoie and R. Keller, "Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts and Motifs in Concert," in Object-Oriented Technology for Database and Software Systems, V. Alagar and R. Missaoui, Eds. Singapore: World Scientific Publishing, 1995, pp. 295-312.

....occurs repeatedly in the problem domain of the framework, and also describes how to solve that problem. Each pattern possesses the same format. The elements of a pattern are: description of its purposes, explanation of how to use it, description of its design, and some examples. Lajoie and Keller [19] introduce the term motif for Johnson s patterns in order to avoid confusion with design patterns. They use a template for a motif description that has a name and intent, a description of the reuse situation, the steps involved in customization, and cross references to motifs, design patterns, and ....

....Contracts can be refined by either specializing the type of a participant, extending its actions, or deriving a new invariant which implies the old. Consequently, the refinement of a contract specifies a more specialized behavioral composition. The role of contracts in Lajoie and Keller s [19] documentation of ET is much more pragmatic than the original intent of Helm et al. A contract supports a cookbook recipe with additional rigor in case a developer needs to consult a specification of collaborative behavior of classes. Design Patterns A design pattern presents a solution to a ....

[Article contains additional citation context not shown here]

Lajoie, R. and Keller, R.K. Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert. In Object-Oriented Technology for Database and Software Systems. V.S. Alagar and R. Missaoui (eds). World Scientific Publishing, Singapore, 1995, pp. 295--312.

....component external interfaces. On the other hand, in order to obtain the maximum benefit from framework reuse, it is necessary to comprehend the internal design of its classes, how these classes collaborate among themselves, as well as the way instances of those classes collaborate at run time [LAJ 94] LAN 95] Reaching a detailed comprehension of these aspects is, in general, an expensive and time consuming task. This aspect can be considered as the most restrictive factor of the technology. In this context, tools that enable the developer to recognize and visualize abstractions of a higher ....

Lajoie, R.; Keller, R. Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. Procs. 62 Congress of the Association Canadienne-Française pour l' Avancement des Sciences, Montreal, Canada, 1994.

....a directed graph indicating the order in which to read them, starting with the main pattern which describes the purpose of the framework. Lajoie and Keller combine the idea of design patterns with Johnson s patterns, which they rename motifs, to provide a more complete description of a framework [12]. In their strategy, motifs point to design patterns, contracts [8] and micro architectures to help provide the developer with an understanding of the architecture of the framework in the context of the problems it was meant to solve. Motifs give advice and examples on how to design solutions to ....

R. Lajoie and R. K. Keller. Design and Reuse in Object Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. In Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences, Montreal, Canada, 1994.

....cookbook. The organization follows a spiral approach where recipes for the most frequent forms of reuse are presented early, and where concepts and details are delayed as long as possible. The first recipe is an overview of the framework concepts and the other recipes. Motif Lajoie and Keller [24] introduce the term motif for Johnson s patterns in order to avoid confusion with design patterns. They use a template for a motif description that has a name and intent, a description of the reuse situation, the steps involved in customization, and cross references to motifs, design patterns, ....

....the agreement between the manager of a reusable asset and the reuser of the asset, so that the effect of newer versions of the asset on the existing reusers can be documented. This is related to version management to support reuse, and is not concerned with the actual reuse. Lajoie and Keller [24] adopt an approach that combines recipes, design patterns, and contracts, all cross referenced to document the ET framework. They do not recognize the different categories of reuse, but the information they document can support each kind of reuse to some degree. Active cookbooks [33] support ....

R. Lajoie and R. K. Keller. Design and reuse in objectoriented frameworks: Patterns, contracts, and motifs in concert. In V. Alagar and R. Missaoui, editors, Object-Oriented Technology for Database and Software Systems, pages 295-- 312, Singapore, 1995. World Scientific.

....the interface semantics of the method. An interaction contract deals with the co operative behavior of several participants that interact to achieve a joint goal. It specifies preconditions on participants required to establish the contract, and the invariant to be maintained by these participants [Lajoie and Keller 1995]. 6 Delta G. Butler, R.K. Keller and H. Mili A design pattern [Gamma et al. 1994] provides an abstraction above the level of classes and objects. Design patterns capture design experience at the microarchitecture level, by specifying the relationship between classes and objects involved in a ....

Lajoie, R. and Keller, R. K. 1995. Design and reuse in object-oriented frameworks: Patterns, contracts, and motifs in concert. In Object-Oriented Technology for Database and Software Systems, pp. 295--312. World Scientific Publishing Co.

No context found.

R. Lajoie and R. Keller, "Design and Reuse in Object-Oriented Frameworks: Patterns, Contracts and Motifs in Concert," in Object-Oriented Technology for Database and Software Systems, V. Alagar and R. Missaoui, Eds. Singapore: World Scientific Publishing, 1995, pp. 295-312.

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R. Lajoie, and R. Keller, "Design and Reuse in ObjectOriented Frameworks: Patterns, Contracts and Motifs in Concert", Object-Oriented Technology for Database and Software Systems, World Scientific Publishing, 1995.

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R. Lajoie and R. K. Keller. Design and Reuse in ObjectOriented Frameworks: Patterns, Contracts, and Motifs in Concert. In Proceedings of the 62nd Congress of the Association CanadienneFrancaisepour l'Avancement des Sciences (ACFAS), Montreal, Canada, May 1994. Colloquium on Object Orientation in Databases and Software Engineering.

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R. Lajoie, R.K. Keller, `Design and Reuse in Object-oriented Frameworks: Patterns, Contracts and Motifs in Concert, ' Proceedings of the 62nd Congress of the Association Canadienne Francaise pour l'Avancement des Sciences, Montreal, Canada, May 1994.

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Lajoie R., Keller R. Design and reuse in object-oriented frameworks: Patterns, Contracts, and Motifs in Concert. In ObjectOriented Technology for Database and Software Systems. V.Alagar, R.Missaoui (eds.), World Scientific Publishing, Singapore, 1995.

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Lajoie, R. and Keller, R.K. 1995. Design and Reuse in Object Oriented Frameworks: Patterns, Contracts, and Motifs in Concert. In Object-Oriented Technology for Database and Software Systems, V.S. Alagar and R. Missaoui (eds), World Scientific Publishing, Singapore. 295-312.

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LaKe94 Lajoie, R. and R.K. Keller. Design and reuse in object-oriented frameworks: patterns, contracts, and motifs in concert. Proceedings of the 62 nd congress of the Association Canadienne Française pour l'Avancement des Sciences (ACFAS), Montreal, Canada, May 1994.

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