Modelling enterprises include two essential tasks:data modelling for static properties and behaviours modelling for dynamic properties.Traditionally,the data modelling and behaviours modelling are separated in differe...Modelling enterprises include two essential tasks:data modelling for static properties and behaviours modelling for dynamic properties.Traditionally,the data modelling and behaviours modelling are separated in different phases and also in different description forms,e.g.the former is modelled in entity-relationship diagrams(ERDs),and the latter is modelled in data flow diagrams (DFDs).The separation could result in an incorrect description of the relationships between da- ta and behaviours,so that the enterprise model couldn't reflect the actual conditions and demands of the enterprise.In this paper an object-oriented approach integrating data with behaviours in a model for the Enterprises Management Information Systems(in short,EMISs)is proposed.As an isomorphic mapping of enterprises an object-oriented model can,in a natural form,exactly describe the dynamic and static properties of enterprises in an integrated model.Therefore it can be easily used by the end-users(e.g.the experts in accounting,financial reporting,and business managers) to specify their demands and communicate with the system analysts and designers.Based on the model an EMIS can be prototyped quickly,and then be conveniently evolved with inheritance mechanism to an adaptive application system according to the actual demands of the enterprise.展开更多
We present a graph-based model of a generic type system for an OO language. The type system supports the features of recursive types, generics and interfaces, which are commonly found in modern OO languages such as Ja...We present a graph-based model of a generic type system for an OO language. The type system supports the features of recursive types, generics and interfaces, which are commonly found in modern OO languages such as Java. In the classical graph theory, we define type graphs, instantia- tion graphs and conjunction graphs that naturally iIlustrate the relations among types, generics and interfaces within complex OO programs. The model employs a combination of nominal and anonymous nodes to represent respectively types that are identified by names and structures, and de- fines graph-based relations and operations on types including equivalence, subtyping, conjunction and instantiation. Algo- rithms based on the graph structures are designed for the im- plementation of the type system. We believe that this type system is important for the development of a graph-based logical foundation of a formal method for verification of and reasoning about OO programs.展开更多
文摘Modelling enterprises include two essential tasks:data modelling for static properties and behaviours modelling for dynamic properties.Traditionally,the data modelling and behaviours modelling are separated in different phases and also in different description forms,e.g.the former is modelled in entity-relationship diagrams(ERDs),and the latter is modelled in data flow diagrams (DFDs).The separation could result in an incorrect description of the relationships between da- ta and behaviours,so that the enterprise model couldn't reflect the actual conditions and demands of the enterprise.In this paper an object-oriented approach integrating data with behaviours in a model for the Enterprises Management Information Systems(in short,EMISs)is proposed.As an isomorphic mapping of enterprises an object-oriented model can,in a natural form,exactly describe the dynamic and static properties of enterprises in an integrated model.Therefore it can be easily used by the end-users(e.g.the experts in accounting,financial reporting,and business managers) to specify their demands and communicate with the system analysts and designers.Based on the model an EMIS can be prototyped quickly,and then be conveniently evolved with inheritance mechanism to an adaptive application system according to the actual demands of the enterprise.
文摘We present a graph-based model of a generic type system for an OO language. The type system supports the features of recursive types, generics and interfaces, which are commonly found in modern OO languages such as Java. In the classical graph theory, we define type graphs, instantia- tion graphs and conjunction graphs that naturally iIlustrate the relations among types, generics and interfaces within complex OO programs. The model employs a combination of nominal and anonymous nodes to represent respectively types that are identified by names and structures, and de- fines graph-based relations and operations on types including equivalence, subtyping, conjunction and instantiation. Algo- rithms based on the graph structures are designed for the im- plementation of the type system. We believe that this type system is important for the development of a graph-based logical foundation of a formal method for verification of and reasoning about OO programs.