The Unified Modeling Language

Exchanging UML model data among tools of different vendors will be done with the technological means developed for the EIA/CDIF interim standards. This paper gives an overview about the development and present state of EIA/CDIF, the metametamodel underlying all of CDIF’s metamodels, the proposed mapping of the UML meta-metamodel to the CDIF meta-metamodel as well as the officially submitted proposal for a CDIF UML-metamodel.

Object-oriented modeling is used in a growing number of commercial software development projects. But the plethora of approaches and corresponding CASE tools still prevents corporate users from migrating to object-oriented software development methods. Against this background the recent efforts of the Object Management Group (OMG) to standardize object-oriented modeling languages seem to promise substantial benefits: Not only will a standard allow to transfer a model from one CASE tool to another it will also protect investment in training. However, at the same time it is questionable whether the state of the art in object-oriented modeling is mature enough to allow for standardization. In order to answer this question, we will briefly describe the proposals submitted to the OMG in January 1997. We will then show that there are still essential problems in designing modeling languages Which have. not been addressed yet.

This paper presents an algorithm to derive class diagrams and consistency guaranteeing constraints formulated using the unified modeling language (UML) form a semantically irreducible formulated conceptual schema.

Originally a global sight to the universe of discourse can be modeled. All limiting assumptions arising from a special application view or implementation language could be taken into account as late as desired.

Nowadays, the Entity-Relationship Model (ERM) is the most important and widely used method for modeling data and designing databases. On the other hand, the Unified Modeling Language (UML) is expected to become more and more popular in object-oriented analysis and design (OOA/OOD). As a by-product of OOA/OOD, a database design can be derived by mapping of objects to entities. The purpose of this paper is to define a mapping between UML and ERM. The translation of a UML class diagram to and from an ER diagram is also elaborated. This work is part of a multi-model multi-tool database application engineering framework that is being designed and prototyped at University Konstanz.

The following article is motivated by the current efforts of the Object Management Group (OMG) to standardize object-oriented modelling languages. In the face of the great economic importance of such a standardization, a careful consideration of possible requirements for modelling languages is necessary. The development of suitable criteria and measures is, however, a delicate task. One reason for this is that the various tasks during the software engineering demand different, partly contradictory, requirements. Beyond this the valuation of quality is not independent from individual preferences and patterns of perception.

In this article, we will give a framework for evaluating modelling languages. We will consider different levels of requirements—from subjective ones, like clarity of notation, to technical ones, like completeness and correctness of the language description Finally we will use this framework for the comparison between OML and UML. An extended version of this comparison can be found in Frank and Prasse (1997).

The Unified Modeling Language consists of a set of mostly graphical description techniques for the specification, modeling, and documentation of object-oriented systems. Based on the experience gained in using UML 1.0 for the development of a medium-sized, distributed Java program, we comment on its strengths and weaknesses. Furthermore, some proposals for extensions and changes are made.

In this paper we show by using the example of UML, how a software engineer­ing method can benefit from an integrative mathematical foundation. The mathematical foundation is given by a mathematical system model. This model provides the basis both for integrating the various description techniques of UML and for implementing methodical support. After describing the basic concepts of the system model, we give a short overview of the UML description techniques. Then we show how they fit into the system model framework and sketch an approach to structure the UML development process such that it provides methodological guidance for developers.

The UML has recently been extended by an Object Constraint Language (OCL). This formal language can be used for specifying constraints on a model in order to restrict possible system states. We present some examples for illustrating main concepts of OCL. Problems with the current definition of OCL resulting from imprecise or ambiguous definitions are investigated. A comparison of OCL with a language for specification of queries and integrity constraints in an Extended Entity-Relationship model shows similarities between both approaches. This comparison could lead to a better understanding of OCL.

Modern programming languages such as Java facilitate the use of concurrent threads of control within computer applications. Considering concurrency is an important prerequisite for the adequate realization of object-oriented ideas, since real world objects usually operate in parallel. This brings up the requirement to be able to express concurrency issues already in design models, which precede implementation activities. The paper examines the possibilities of modeling Java threads using the Unified Modeling Language (UML). UML is the official industry standard for object-oriented modeling as defined by the Object Management Group (OMG).

UML is the first OO modeling language with a useful modularization and information hiding concept. It supports nesting, import, and refinement of so-called packages. This paper translates UML’s informal package definition into predicate logic formulas and solves some open problems concerning the visibility of exported and imported modeling elements.

Furthermore, the formulas will be transformed into a specification based on PROgrammed Graph REwriting Systems. We will very briefly sketch how a graphical UML editor can be generated from this PROGRES specification.

Specialization is often considered being one of the crucial semantic operators in object-oriented modeling. Yet the ways of handling and interpreting this semantic construct differ highly from method to method. It is not only the lack of a precise definition the user of a method has to cope with, but also an in most cases missing discussion or simple indication of the implied consequences on the process of modeling, the resulting models, and the transformation into an implementation. In this respect even the Unified Modeling Language (UML) must not be considered an exception.

The following paper starts with a comparative look at different object-oriented modeling methods and the suggested ways of handling specialization. The differences can be partially explained by looking at the underlying basic classification approaches. These approaches are discussed with respect to consequences on modeling and implementing and correspondence to implementation technologies. The paper closes with a look at the UML while taking into account the previous results.

If the UML finally becomes a standard for a object-oriented notation we have a precise metamodel description for making the interchange of model data possible which allows the reuse of model elements of the OOA and OOD as well. The UML just offers a notation and does not impose a method. According to that the developer is free to combine the diagrams of the UML according to the metamodel to cope with the domain requirements. As an example, it is possible to assign state diagrams and activity diagrams to classes, operations and use cases — the mentioned interchange of model data involves sequences of diagrams and whole models, not just single diagrams. Now the developers problem is that based on missing methods for the UML there is a lack of consistency rules concerning the combination of its diagrams. The semantics for diagram assignments are not clearly defined. As a result the software developer gets no help for transferring the results of the OOD to an implementation. The UML does not solve the problem of the discontinuity between OOA, OOD and the level of implementation. The UML does not fill in the gaps of the given OO methods but widens these gaps. We want to demonstrate these problems regarding the association between a class and a state diagram: When a class A has a state diagram class B inherits the complete properties of class A for its behavioral description, the result is implicit inheritance of A’s state diagram. We chose the correlation of classes and state diagrams because state diagrams are a very important means for detailed modeling of complex dynamics At least the most important OO methods have state diagrams as its heart.

The telecommunication market is one of the fastest growing markets in the last years. Deregulation in the provider market, new techniques and user demands lead to more flexibility but require also the coexistence of legacy telecommunication systems with new and more advanced technologies. Although being known conservative in the introduction of new technologies, the new requirements have forced the industry to increase the time-to-market for new services and to apply new reference architectures. This paper investigates, how the new object oriented modeling language UML (Unified Modeling Language) can be applied in this domain.

The development of business information systems based on business object components as defined by the OMG is going to complement and simplify the conventional approach to object-oriented software development. The intention is to enable end users and business experts to assemble “plug-and-play” business objects without the help of IT experts. In spite of the reduction of complexity to be expected, a model-based approach to systems development is still essential. Business objects are not only well suited as modeling concepts in software engineering, they may even be used in the context of business engineering. This paper describes different aspects of modeling business objects with the Unified Modeling Language and evaluates its aptitude for that purpose.

The V-Model is an international recognized development standard for IT-systems which was developed by Industrieanlagen — Betriebsgesellschaft (IABG) on behalf of the German Ministery of Defense (BMVg) and was also taken over by the German Federal Ministery of the Interior. It is a generic process framework, that can be adapted to each type of system development project. The new version of the V-Model has integrated perfectly smooth the UML-Methods in the second level of the standard.

Process and object-orientation are basic concepts of modeling, implementing and customizing information systems. In this paper we present two approaches of combining those concepts into a coherent way. In the first approach we discuss how to transform business process models (Event-driven Process Chain (EPC) diagrams) into object-oriented models (Unified Modeling Language (UML) diagrams). The main focus is to support the co-existence of both modeling methods focusing on the modeling context. The second approach deals with the integration of both modeling methods extending the EPC-model by business object classes.

We describe our experiences with the use of the Unified Modeling Language (UML) in a job floor control system project. Firstly, we analyze what is new for the daily project work when using UML. The powerfulness and the extensibility of the UML, its changing character at the moment, and insufficiencies of the available tools make conventions a very important aspect of UML use in the practice. We give some examples of naming and structuring conventions and show how workarounds influence modeling.

In this contribution at first the Unified Modeling Language (UML) on the basis of the different diagrams (Class-Structure-, Use-Case-, Sequence-, Collaboration-, Component-, Distribution-, State-and Activity diagram) is briefly introduced as the result of the efforts to standardize modeling languages. Furthermore, the framework of an activity flow model for the software development in professional projects is introduced. Basing on this framework a possible activity flow model for the software development on the basis of UML is introduced, which has been adapted to a professional project of a leading german organisation in the banking sector.