Citation Context

...rocess that we adopted for reorganizing the source code. 1. Introduction In recent years, Component Based Software Development (CBSD) has attracted considerable interest from both the research and industry areas, and it is fast becoming the principal paradigm in Software Engineering. However, although today some commercial frameworks (e.g. EJB [12], .NET [13], CCM [11]) permit the actual realization of component-based applications, the research is far from complete, and further studies are necessary especially regarding component specifications, development methodologies and development tools [7]. The reason for the widespread diffusion of the CB paradigm is due to the increasing complexity of current developed systems. They are often characterized by distributed features, remote accessibility and high evolvability, i.e., the system must be easily expanded with new functionalities or improved by modifying the existing code without affecting the services already provided. To comply with the strict delivery times imposed by the market, the developers of complex systems use experiences coming from various research and industry fields such as software architecture (SA), component-based so...

Citation Context

... common vocabulary useful for avoiding misunderstanding and ambiguities. It is represented by a class model, but the classes involved, as well as their associations, are only conceptual and not related to the specification. Instead, the use case model represents the interaction of the system with the external users. It is represented by a Use Case Diagram, in which each Use Case is related to a different requirement or functionality. The system behavior and the main exceptions are represented for each Use Case in the associated scenario, following the textual structure of Cockburn’s Use Cases [3]. The specification workflow is subdivided into three phases: i identification of the components: starting from the requirements, an initial system architecture is produced; ii interactions among the components, which identify the system’s operations and responsibilities; iii specification of the components, which specifies the operations and interfaces of the components themselves. A business type model, represented by a class diagram, is used for modelling the entities of the business concept model actually perceived by the system. The involved classes are defined at the specification level,...

Citation Context

... for each capability. Thus, it is natural to realize a component Connection Factory whose goal is to create an instance of a proper Connection object for the requests coming from the different JAIN Providers. 3. UML Components In this section we briefly present the methodology proposed by Cheesman and Daniels [2], called the UML Component, which focuses on both the representation of the components, and the process development applicable for this purpose. In particular we report the main details of the specification process adopted in [2], divided into interacting workflows as suggested by RUP [4]. The first one is the requirement workflow, which produces the business concept model and the use case model [10]. The former is a conceptual model, which specifies the key concepts, their relations and a common vocabulary useful for avoiding misunderstanding and ambiguities. It is represented by a class model, but the classes involved, as well as their associations, are only conceptual and not related to the specification. Instead, the use case model represents the interaction of the system with the external users. It is represented by a Use Case Diagram, in which each Use Case is related to...

Citation Context

...l ones which must conform to the logical structure. In this step, the real components can be retrieved either from the market or from inside the organization, or implemented from scratch. One of the emerging trends in CBSD is the use of UML [10] for system specification, which is the de facto standard notation for the analysis and design of Object Oriented (OO) systems. Even if UML was not conceived with a component-based paradigm in mind, by its extensions mechanisms, it proves to be flexible enough to be adaptable to different contexts. Thanks to this characteristic, Cheesman and Daniels in [2] propose an innovative methodology, called UML Components, which focuses both on the representation of components and on the development process applicable for this purpose. Therefore the advent of the CB paradigm has opened a new and promising approach for the refactoring of legacy systems [6, 8]. In this paper we apply the UML Component methodology for designing and re-implementing an additional layer over protocol GSM-MAP, used in the telecommunication context for mobility management and other services. Our objective is to define a suitable system architecture which can be used for re-organ...

Citation Context

...logy proposed by Cheesman and Daniels is a defined development process to follow in order to obtain a well-structured and working system, which facilitates UML specification, code restructuring and testing. Of course, other development processes could be adopted for the same purpose, but are beyond the scope of this paper either deeper investigation of this topic or providing a comparison between them. We adopted UML Components because it is an innovative methodology for defining a complete UML architecture specification, which can be used as an input to some existing tools, such as Cow Suite [1], in order to reduce the effort due for testing phase development. Thus, in this paper we report our experience by describing the steps of the process adopted, by pointing out the difficulties encountered and the problems faced in applying the UML Components, even if due to space limitations we present only the main results. During system architecture specification it was not always easy to follow this methodology faithfully, because our case study is quite different from that presented in [2]. In their book Cheesman and Daniels use as a case study a data management system, whose organization ...

Citation Context

...tandard notation for the analysis and design of Object Oriented (OO) systems. Even if UML was not conceived with a component-based paradigm in mind, by its extensions mechanisms, it proves to be flexible enough to be adaptable to different contexts. Thanks to this characteristic, Cheesman and Daniels in [2] propose an innovative methodology, called UML Components, which focuses both on the representation of components and on the development process applicable for this purpose. Therefore the advent of the CB paradigm has opened a new and promising approach for the refactoring of legacy systems [6, 8]. In this paper we apply the UML Component methodology for designing and re-implementing an additional layer over protocol GSM-MAP, used in the telecommunication context for mobility management and other services. Our objective is to define a suitable system architecture which can be used for re-organizing some of the already implemented functionalities in a componentbased manner, by reducing modification and code rewriting as much as possible. In our case, in fact, the available pieces of software, each related to a different functionality, were developed during the course of several Master’s...

Citation Context

...tandard notation for the analysis and design of Object Oriented (OO) systems. Even if UML was not conceived with a component-based paradigm in mind, by its extensions mechanisms, it proves to be flexible enough to be adaptable to different contexts. Thanks to this characteristic, Cheesman and Daniels in [2] propose an innovative methodology, called UML Components, which focuses both on the representation of components and on the development process applicable for this purpose. Therefore the advent of the CB paradigm has opened a new and promising approach for the refactoring of legacy systems [6, 8]. In this paper we apply the UML Component methodology for designing and re-implementing an additional layer over protocol GSM-MAP, used in the telecommunication context for mobility management and other services. Our objective is to define a suitable system architecture which can be used for re-organizing some of the already implemented functionalities in a componentbased manner, by reducing modification and code rewriting as much as possible. In our case, in fact, the available pieces of software, each related to a different functionality, were developed during the course of several Master’s...