Browsing by Subject "Generic Modeling Environment (GME)"

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    AUTO-GENERATING MODELS FROM THEIR SEMANTICS AND CONSTRAINTS
    (Office of the Vice Chancellor for Research, 2012-04-13) Pati, Tanumoy; Hill, James H.
    Model-Driven Engineering (MDE) facilitates building solutions in many en-terprise application domains through the systematic use of graphical lan-guages called domain-specific modeling languages (DSMLs). MDE tools, such as the Generic Modeling Environment (GME) and the Generic Eclipse Modeling System (GEMS), enable end-users to rapidly create such custom DSMLs. When DSMLs are coupled with constraint solvers, it is possible for DSML end-users to auto-generate solutions (i.e., models) based on the goals of the constraint solver (e.g., finding the optimal deployment for a set of software components given resource availability and resource needs). One requirement of using a constraint solver with a DSML, however, is that mod-elers have to create an initial model, also known as a “partial model”. This implies that it is the end-users responsibility to (1) understand how to use the DSML and (2) understand when they have created an appropriate partial model that is a candidate for completion using a constraint solver. Our research therefore focuses on addressing the two problems men-tioned above. We address the problems by analyzing the semantics and con-straints of the DSML (i.e., the meta-model). Based on our analysis, we then auto-generate as much of the model until we reach a point that requires us-er intervention. At that point, we present a set of operations (or moves) to the user and continue the process until the model is complete, or is solvable using a constraint solver.
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    A VERY FAST CONSTRAINT SOLVER INTERPRETER FOR EVALUATING MODEL CONSTRAINTS
    (Office of the Vice Chancellor for Research, 2016-04-08) Nair, Arvind; Hill, James H.
    Model-Driven Engineering (MDE) facilitates building solutions in many enterprise application domains through the systematic use of graphical languages called domain-specific modeling languages (DSMLs). MDE tools, such as the Generic Modeling Environment (GME) and the Generic Eclipse Modeling System (GEMS), enable end-users to rapidly create such custom DSMLs. One advantage of using DSMLs is its correct-by-construction characteristics, which is provided by domain-specific constraints defined within these custom languages. The constraints, written in Object Constraint Language (OCL), are evaluated during and after model construction using a constraint checker. For example, GME provides a Constraint Manager (CM) that evaluate the constraints defined by a DSMLs against its models. Unfortunately, our experience has shown that the constraint checkers provided by MDE tools do not scale to large models (i.e., models that have 10s of 1000s of model elements and 10s of 100s of constraints). Our research therefore focuses on developing a very fast OCL constraint solver that can address the current shortcomings of existing OCL constraint solvers in the context of GME. Our design approach leverages best practices in software design patterns, caching, and multi-threading to improve its performance and scalability. Initial results of our work show that for small models (e.g., 10s to 100s of elements), the traditional constraint solvers run slightly faster than our approach. For models with more than 1000s of elements, our approach is twice as fast, and performs exponential better as the size and complexity of the models increase.