Katrin Hölldobler

Engineering delta modeling languages

Delta modeling is a modular, yet flexible approach to capture spatial and temporal variability by explicitly representing the differences between system variants or versions. The conceptual idea of delta modeling is language-independent. But, in order to apply delta modeling for a concrete language, so far, a delta language had to be manually developed on top of the base language leading to a large variety of heterogeneous language concepts. In this paper, we present a process that allows deriving a delta language from the grammar of a given base language. Our approach relies on an automatically generated language extension that can be manually adapted to meet domain-specific needs. We illustrate our approach using delta modeling on a textual variant of statecharts.

A comparison of mechanisms for integrating handwritten and generated code for object-oriented programming languages

Code generation from models is a core activity in model-driven development (MDD). For complex systems it is usually impossible to generate the entire software system from models alone. Thus, MDD requires mechanisms for integrating generated and handwritten code. Applying such mechanisms without considering their effects can cause issues in projects with many model and code artifacts, where a sound integration for generated and handwritten code is necessary. We provide an overview of mechanisms for integrating generated and handwritten code for object-oriented languages. In addition to that, we define and apply criteria to compare these mechanisms. The results are intended to help MDD tool developers in choosing an appropriate integration mechanism.

Systematically deriving domain-specific transformation languages

Model transformations are helpful to evolve, refactor, refine and maintain models. While domain-specific languages are normally intuitive for modelers, common model transformation approaches (regardless of whether they transform graphical or textual models) are based on the modeling languages abstract syntax requiring the modeler to learn the internal representation of the model to describe transformations. This paper presents a process that allows to systematically derive a textual domain-specific transformation language from the grammar of a given textual modeling language. As example, we apply this systematic derivation to UML class diagrams to obtain a domain-specific transformation language called CDTrans. CDTrans incorporates the concrete syntax of class diagrams which is already familiar to the modeler and extends it with a few transformation operators. To demonstrate the usefulness of the derived transformation language, we describe several refactoring transformations.

Integration of Handwritten and Generated Object-Oriented Code

In many development projects models are core artifacts used to generate concrete implementations from them. However, for many systems it is impossible or not useful to generate the complete software system from models alone. Hence, developers need mechanisms for integrating generated and handwritten code. Applying such mechanisms without considering their effects can cause issues in projects, where model and code artifacts are essential. Thus, a sound approach for the integration of both forms of code is needed.

Systematic synthesis of delta modeling languages

Delta modeling is a modular, yet flexible approach to capture variability by explicitly representing differences between system variants or versions. The conceptual idea of delta modeling is language-independent. But, to apply delta modeling to a concrete language, either a generic transformation language has to be used or the corresponding delta language has to be manually developed for each considered base language. Generic languages and their tool support often lack readability and specific context condition checking, since they are unrelated to the base language. In this paper, we present a process that allows synthesizing a delta language from the grammar of a given base language. Our method relies on an automatically generated language extension that can be manually adapted to meet domain-specific needs. We illustrate our method using delta modeling on a textual variant of architecture diagrams. Furthermore, we evaluate our method using a comparative case study. This case study covers an architectural, a structural, and a behavioral language and compares the preexisting handwritten grammars to the generated grammars as well as the manually tailored grammars. This paper is an extension of Haber et al. (Proceedings of the 17th international software product line conference (SPLC’13), pp 22–31, 2013).

Advances in Modeling Language Engineering

The increasing complexity of modern systems development demands for specific modeling languages capturing the various aspects to be tackled. However, engineering of comfortable modeling languages as well as their tooling is a challenging endeavor. Far too often, new languages are built from scratch. We shed light into the advances of modeling language engineering that facilitates reuse, modularity, compositionality and derivation of new languages based on language components. We discuss ways to design, combine, and derive modeling languages in all their relevant aspects. For each of these activities, we illustrate their application for the model-driven development of a data exploration tool. The tool itself uses a set of meta-information, namely the structural model to derive all necessary software components that help to gather, store, visualize and navigate the data.

Adaptable symbol table management by meta modeling and generation of symbol table infrastructures

Many textual software languages share common concepts such as defining and referencing elements, hierarchical structures constraining the visibility of names, and allowing for identical names for different element kinds. Symbol tables are useful to handle those reference and visibility concepts. However, developing a symbol table can be a tedious task that leads to an additional effort for the language engineer. This paper presents a symbol table meta model usable to define language-specific symbol tables. Furthermore, we integrate this symbol table meta model with a meta model of a grammar-based language definition. This enables the language engineer to switch between the model structure and the symbol table as needed. Finally, based on a grammar annotation mechanism, our approach is able to generate a symbol table infrastructure that can be used as is or serve as a basis for custom symbol tables.

Software language engineering in the large: towards composing and deriving languages

Abstract Suitable software languages are crucial to tackling the ever-increasing complexity of software engineering processes and software products. They model, specify, and test products, describe processes and interactions with services and serve many other purposes. Meanwhile, engineering suitable modeling languages with useful tooling also has become a challenging endeavor - and far too often, new languages are developed from scratch. We shed light on the advances of modeling language engineering that facilitate reuse, modularity, compositionality, and derivation of new languages based on language components. To this end, we discuss ways to design, combine, and derive modeling languages in all their relevant aspects. We illustrate the application of advanced language engineering throughout the paper, which culminates in the example of deriving complete domain-specific transformations language from existing language components.