Second, the top-level model is broken downward, and the model of each subsystem of the system is established, and these sub-models are simulated, analyzed and adjusted. The simulation result of the child model is then subjected to the upper layer, and then further simulates, analyzes, and adjusts the upper layer model. If it is not suitable, modification is made. Therefore, the entire modeling process is a "self-top molding, and modified by the bottom upward". Briefly, the flexible software development process is a demand traction, which is refined from the top downwardly, and then according to the "T-type technology", through the virtual execution of the model, the bottom is upward Modify until the simulation results of the layers meet demand. The generation of code is based on the correctness of the model, considering the "closed loop development" that can feedback modification at the same time considering the flexibility and fast response capability of demand modification. That is, it can not only support automatic generation from the model to code, convert the new model to code, but also support the reverse transformation from the code to the model, transform the original code into model, re-analyze, modify and adjust, and new one The development is supported for increasing development. This can not only be submitted in phases, but also improve the response speed and strain ability to change user demand, to meet the new demand for users. (2) The basic demand for the UML support environment is based on the above theory and our five-year experience in developing and developing integrated software engineering environments. A perfect integrated process engineering environment should meet the following basic needs: · It should be able to support the development of a complete process model (ie five sides such as process, resources, institutions, behaviors, and information) and system models (that is, from process, behavior, information, and structures) Side to describe a system). • The model established under this environment should be an executable process (system) model, which should support the virtual execution (simulation) and actual operation of the model, so that the model can be analyzed and optimized at different levels. · Process (system) model should adopt a visualized icon and a body description, and the structure of its visual model map should be objectively, naturally reflecting communication and synchronization relationship between enterprises and institutions. • It should be able to support modeling people or managers to flexibly control the implementation of the model in accordance with the constraint conditions inside and outside the enterprise (system), thereby achieving crossover crossings and management processes. · It should be supported from the model automatic generation to run on the Internet and support multi-platform sharing and multi-project inventory to achieve strong support for the automation of the third generation process engineering. · It should also support the flexible management of various component libraries, support component-based programming methods, implement process components, demand description, multiplexing and assembly of software components. UML Integrated Support Environment Countermeasures Supply Project Construction Environment and Integrated System Engineering Environment provides strong technical support. On the one hand, three of the functions and interfaces must be seamlessly connected, and the three in the style must be coordinated. At the division, the goal of the process engineering environment is to optimize the process. The goal of the system engineering environment is to automatically generate an optimized computer application system, and the UML support environment is to provide technical support to complement flexible computer application. 3. UML Integrated Support Environment The UML Integration Support Environment is a system development environment that supports construction flexible information systems under demand traction. Its composition should include UML visual modeling system, analog system, code generation system, reverse conversion system, quality control. System and its support software, etc. These environments should be based on the syntax rules and semantic definitions of UML, as shown in Figure 1. It can be seen that this support environment is an integrated support environment that supports "closed-loop development" generated by system modeling, system simulation, and system generated. (1) UML Visual Modeling System Frame UML Visual Modeling System Supports the entire modeling process of system design, system analysis to system design, providing editing and beautifying tools for UM L graphics, ensuring the correct, semantic integrity UML Graphics models and provide assistive support including document management and graphic printing. The modeling mechanism for supporting the environment Since UML not only supports the model model of the system, it also supports the modeling of demand and system architecture, which not only supports the establishment of a static model of the system, but also supports the dynamic model of the system, therefore, the model construction system The following models should be supported: The demand model includes a static model and a dynamic model. The static model is a functional model, and the relationship between the system functions and the potential users of each function are described in UML. The dynamic model supports a description of the business process or transaction process through the active diagram. The system object model includes a static model and a dynamic model. Define a static relationship between system objects and objects by a package diagram, class diagram, and object diagram; through sequential diagrams, cooperation diagrams describing the interaction between objects, the live cycle of the object, and the state of the object may exist in the lifecycle. Conversion constraints.
The system architecture model supports software architectural and hardware architectural structures and definitions of communication mechanisms by component diagrams and configuration graphs. At the same time, it should further support the visual representation of the cooperative relationship between the hardware and software system. The detection mechanism of the modeling system UML syntax correctness detection mechanism is to ensure that the obtained UML graphics model is in line with its syntax definition, and the syntax correctness detection mechanism should be provided. A preferred method is to provide the syntax-guided UML visual modeling tool, providing dynamic grammar guidance and grammar detection function during the construction of the model. In this way, it is convenient for users to learn and use, and it is also possible to ensure the correctness of the built model in the grammatical structure. UML model consistency inspection mechanism Since UML supports from demand analysis to the system design of the entire modeling process, support users from different perspective description systems, and the collaboration and constraint between large software projects are intricate, it should not be Alone bear the management and maintenance of them. As a modeling support system, a consistent inspection mechanism between the model should be provided. First, the mechanism should be based on the above discussion based on the UML software development model, and the time to introduce the model is determined on the time axis of the software development phase; secondly, it is clear that the refined hierarchy mechanism of the same model, and how to describe the main model with other models Detail; third, on the software development phase time axis, a model exists in the hierarchy of the top-down decomposition, in the hierarchy generated in each time phase, various UML models are constrained, and cooperative and complex mesh Relationship, the same model of different stages, the same model of different functions, and the mathematical model of different model constraints; Finally, on the basis of this mathematical model, research will be the same as the model of the constraint and collaborative relationships. Sexual inspection mechanism. Further, since the same model is allowed from different angles, such as the interaction map includes a sequence diagram and a cooperation diagram, there is redundant information between the two, but therefore, not only the consistency between the two information is not only, but also support Consistency conversion between the model. The complete check mechanism complete check mechanism of the UML model must first define a complete guidelines for the UML graphics model to ensure the completeness of the UML graphics model on the basis of the UML semantic definition. The completeness of the UML graphics model can be considered in three hierarchies: the completeness of each graphic; the completeness of each sub-model, that is, the combination of related graphics; the overall completeness of the system model. Significance of these three completeness is that semantic completeness and semantic correctness check can be performed at different stages. Document Generation and Management Tool Documentation Generation Tool refers to a document automatic generation mechanism. As a modeling support system, it should be supported automatic generation of document data such as demand, object-oriented analysis and design, system architecture, and other document data. Document Management Tools are auxiliary management of version management of documentation. (2) UML analog system system simulation mechanism supports functional simulation and performance simulation of UML models, including the following three parts: The simulation of the dynamic model mainly includes the active model, interactive model (sequential diagram and cooperation map) and status maps simulation. Depending on the predefined semantics, the simulation of each model has truly reflects objective reality and user needs on the description of the system in time characteristics, and should provide the corresponding tracking debug mechanism. System function (demand) and user interface simulation uses to automatically generate tools for code automatic generation tools and user interfaces, generate system prototypes, and provide users to ensure effectiveness of modeling. System performance simulation as a good modeling and development support tool to support the modeling of system architecture, that is, in the case of different system configuration and function assignment, simulate system performance in order to obtain an optimized system design And a reasonable system configuration. (3) UML code generation system UML integrated support environment should support code generation of visual objects and behavior. The UML code generation system is also called a forward transform system for the UML support environment. It is well known that the ultimate goal of software development is to generate executable code. In most software development environments, modeling and encoding processes lack organic unity, this is there is historical reasons. The most important reason is the lack of powerful, simple and clear, standard unified modeling languages. The emergence of UML and is accommodated by OMG, providing a good starting point for eliminating this obstacle. In terms of UML language code generation mechanism, some major companies have made beneficial research and development work, which is relatively represented by Rational Company and Advanced Software Technologies Inc. However, these research and implementation are limited to class diagrams in the UML static model, and other research materials related to model code automatic generation mechanism are very rare. We believe that the code automatic generation mechanism should dynamically collaborate dynamically according to the UML language, the complex feature, first defining the semantics of the UML and object-oriented programming language (first is Java), study the dedicated semantic mechanism Description Object-oriented model and language The dynamic and static mechanisms, establish a semantic model of both.
