Analyzing Consistency of Behavioral REST Web Service Interfaces

REST web services can offer complex operations that do more than just simply creating, retrieving, updating and deleting information from a database. We have proposed an approach to design the interfaces of behavioral REST web services by defining a resource and a behavioral model using UML. In this paper we discuss the consistency between the resource and behavioral models that represent service states using state invariants. The state invariants are defined as predicates over resources and describe what are the valid state configurations of a behavioral model. If a state invariant is unsatisfiable then there is no valid state configuration containing the state and there is no service that can implement the service interface. We also show how we can use reasoning tools to determine the consistency between these design models.Comment: In Proceedings WWV 2012, arXiv:1210.578

Consistency of UML based designs using ontology reasoners

Software plays an important role in our society and economy. Software development is an intricate process, and it comprises many different tasks: gathering requirements, designing new solutions that fulfill these requirements, as well as implementing these designs using a programming language into a working system. As a consequence, the development of high quality software is a core problem in software engineering. This thesis focuses on the validation of software designs. The issue of the analysis of designs is of great importance, since errors originating from designs may appear in the final system. It is considered economical to rectify the problems as early in the software development process as possible. Practitioners often create and visualize designs using modeling languages, one of the more popular being the Uni ed Modeling Language (UML). The analysis of the designs can be done manually, but in case of large systems, the need of mechanisms that automatically analyze these designs arises. In this thesis, we propose an automatic approach to analyze UML based designs using logic reasoners. This approach firstly proposes the translations of the UML based designs into a language understandable by reasoners in the form of logic facts, and secondly shows how to use the logic reasoners to infer the logical consequences of these logic facts. We have implemented the proposed translations in the form of a tool that can be used with any standard compliant UML modeling tool. Moreover, we authenticate the proposed approach by automatically validating hundreds of UML based designs that consist of thousands of model elements available in an online model repository. The proposed approach is limited in scope, but is fully automatic and does not require any expertise of logic languages from the user. We exemplify the proposed approach with two applications, which include the validation of domain specific languages and the validation of web service interfaces

Metamodel-based model conformance and multiview consistency checking

Model-driven development, using languages such as UML and BON, often makes use of multiple diagrams (e.g., class and sequence diagrams) when modeling systems. These diagrams, presenting different views of a system of interest, may be inconsistent. A metamodel provides a unifying framework in which to ensure and check consistency, while at the same time providing the means to distinguish between valid and invalid models, that is, conformance. Two formal specifications of the metamodel for an object-oriented modeling language are presented, and it is shown how to use these specifications for model conformance and multiview consistency checking. Comparisons are made in terms of completeness and the level of automation each provide for checking multiview consistency and model conformance. The lessons learned from applying formal techniques to the problems of metamodeling, model conformance, and multiview consistency checking are summarized

A Formal Metamodeling Approach to a Transformation between Visual and Formal Modeling Techniques

Formal modeling notations and visual modeling notations can complement each other when developing software models. The most frequently adopted approach is to define transformations between the visual and formal models. However, a significant problem with the currently suggested approaches is that the transformation itself is often described imprecisely, with the result that the overall transformation task may be imprecise, incomplete and inconsistent. This paper presents a formal metamodeling approach to transform between UML and Object-Z. In the paper, the two languages are defined in terms of their formal metamodels, and a systematic transformation between the models is provided at the meta-level in terms of formal mapping functions. As a consequence, we can provide a precise, consistent and complete transformation between a visual model in UML and a formal model in Object-Z

Software System Model Correctness using Graph Theory: A Review

The Unified Modeling Language UML is the de facto standard for object-oriented software model development The UML class diagram plays an essential role in design and specification of software systems The purpose of a class diagram is to display classes with their attributes and methods hierarchy generalization class relationships and associations general aggregation and composition between classes in one mode

UML models consistency management: guidelines for software quality manager

Unified Modeling Language (UML) has become the de-facto standard to design today’s large-size object-oriented systems. However, focusing on multiple UML diagrams is a main cause of breaching the consistency problem, which ultimately reduces the overall software model’s quality. Consistency management techniques are widely used to ensure the model consistency by correct model-to-model and model-to-code transformation. Consistency management becomes a promising area of research especially for model-driven architecture. In this paper, we extensively review UML consistency management techniques. The proposed techniques have been classified based on the parameters identified from the research literature. Moreover, we performed a qualitative comparison of consistency management techniques in order to identify current research trends, challenges and research gaps in this field of study. Based on the results, we concluded that researchers have not provided more attention on exploring inter-model and semantic consistency problems. Furthermore, state-of-the-art consistency management techniques mostly focus only on three UML diagrams (i.e., class, sequence and state chart) and the remaining UML diagrams have been overlooked. Consequently, due to this incomplete body of knowledge, researchers are unable to take full advantage of overlooked UML diagrams, which may be otherwise useful to handle the consistency management challenge in an efficient manner

The Design and Implementation of a Query Platform and Simulation Tool for the Analysis of UML State Machines through Declarative Modeling

Among the various aspects of the UML, a state machine is part of the specification used to model the dynamic behavior of systems. In developing complex systems, state machines can be deployed to capture use cases and thus contribute towards requirements validation. During testing, a state machine can contribute towards requirements verification. In our proposal, we treat a state machine as a directed mathematical graph and transform it into a declarative model that is implemented as a database of clauses using Prolog. To tackle the complexity of composite states, we propose an algorithm for flattening the representation of a state machine. This model transformation occurs behind the scenes and provides the same semantic model at a lower level of abstraction. The initial and flattened declarative models provide the factbase on which we build a set of rules to study the behavior, the complexity and the structure of a state machine. Furthermore, we treat the machine’s flattened model as a platform over which we simulate the machine’s behavior given a scenario. We support the simulation process with a tool that we developed. The tool is implemented in Java using the Java Prolog Library (JPL) that provides an interface between the two technologies. Our simulator reads in a scenario and proceeds to generate the machine’s behavior including its state at discrete time steps as output. We demonstrate the process through a case study

An Operator-based Approach to Incremental Development of Conform Protocol State Machines

An incremental development framework which supports a conform construction of Protocol State Machines (PSMs) is presented. We capture design concepts and strategies of PSM construction by sequentially applying some development operators: each operator makes evolve the current PSM to another one. To ensure a conform construction, we introduce three conformance relations, inspired by the specification refinement and specification matchings supported by formal methods. Conformance relations preserve some global behavioral properties. Our purpose is illustrated by some development steps of the card service interface of an electronic purse: for each step, we introduce the idea of the development, we propose an operator and we give the new specification state obtained by the application of this operator and the property of this state relatively to the previous one in terms of conformance relation