Judith A. Stafford

The Past, Present, and Future for Software Architecture

Its been 10 years since David Garlan and Mary Shaw wrote their seminal book Software Architecture Perspective on an Emerging Discipline, since Maarten Boasson edited a special issue of IEEE Software on software architecture, and since the first International Software Architecture Workshop took place. What has happened over these 10 years? What have we learned? Where do we look for information? Whats the community around this discipline? And where are we going from here?This article is part of a focus section on software architecture.

ARCHITECTURE-LEVEL DEPENDENCE ANALYSIS FOR SOFTWARE SYSTEMS

The emergence of formal software architecture description languages provides an opportunity to perform analyses at high levels of abstraction, as well as early in the development process. Previous research has primarily focused on developing techniques such as algebraic and transition-system analysis to detect component mismatches or global behavioral incorrectness. In this paper we motivate the utility and describe the challenges in developing a different kind of analysis for use at the architectural level, namely dependence analysis. Various kinds of dependence analyses have been used widely at the implementation level to aid program optimization, anomaly checking, program understanding, testing, and debugging. However, the languages used for architectural description offer quite different features than the languages for which traditional dependence analysis techniques have been developed. We describe our initial approach to architecture-level dependence analysis and illustrate that approach through a prototype tool we have built, called Aladdin, to automatically perform the analysis.

Architecting Systems with Trustworthy Components

Performance predictions of component assemblies and the ability of obtaining system-level performance properties from these predictions are a cru- cial success factor when building trustworthy component-based systems. In order to achieve this goal, a collection of methods and tools to capture and analyze the performance of software systems has been developed. These methods and tools aim at helping software engineers by providing them with the capability to understand design trade-offs, optimize their design by identifying performance inhibitors, or predict a systems performance within a specified deployment envi- ronment. In this paper, we analyze the applicability of various performance pre- diction methods for the development of component-based systems and contrast their inherent strengths and weaknesses in different engineering problem scenar- ios. In so doing, we establish a basis to select an appropriate prediction method and to provide recommendations for future research activities, which could sig- nificantly improve the performance prediction of component-based systems.Invited Articles.- Audition of Web Services for Testing Conformance to Open Specified Protocols.- A Core Theory of Interfaces and Architecture and Its Impact on Object Orientation.- Making Specifications Complete Through Models.- Bus Scheduling for TDL Components.- Refinement and Consistency in Component Models with Multiple Views.- Articles by Participants.- A Taxonomy on Component-Based Software Engineering Methods.- Unifying Hardware and Software Components for Embedded System Development.- On the Composition of Compositional Reasoning.- Trustworthy Instantiation of Frameworks.- Performance Prediction of Component-Based Systems.- Towards an Engineering Approach to Component Adaptation.- Compatible Component Upgrades Through Smart Component Swapping.- Exceptions in Component Interaction Protocols - Necessity.- Coalgebraic Semantics for Component Systems.- A Type Theoretic Framework for Formal Metamodelling.

Quality of Software Architectures and Software Quality

Keynotes.- Reexamining the Role of Interactions in Software Architecture.- Are Successful Test Cases Useless or Not?.- QoSA Long Papers.- DoSAM - Domain-Specific Software Architecture Comparison Model.- An Architecture-Centric Approach for Producing Quality Systems.- A Model-Oriented Framework for Runtime Monitoring of Nonfunctional Properties.- Predicting Mean Service Execution Times of Software Components Based on Markov Models.- An XML-Based Language to Support Performance and Reliability Modeling and Analysis in Software Architectures.- Formal Definition of Metrics Upon the CORBA Component Model.- The Architects Dilemma - Will Reference Architectures Help?.- Architectural Reuse in Software Systems In-house Integration and Merge - Experiences from Industry.- Supporting Security Sensitive Architecture Design.- Exploring Quality Attributes Using Architectural Prototyping.- On the Estimation of Software Reliability of Component-Based Dependable Distributed Systems.- Empirical Evaluation of Model-Based Performance Prediction Methods in Software Development.- SOQUA Long Papers.- Automatic Test Generation for N-Way Combinatorial Testing.- Automated Generation and Evaluation of Dataflow-Based Test Data for Object-Oriented Software.- Automated Model-Based Testing of ? Simulation Models with TorX.- Jartege: A Tool for Random Generation of Unit Tests for Java Classes.- FlexTest: An Aspect-Oriented Framework for Unit Testing.- Quality Assurance in Performance: Evaluating Mono Benchmark Results.

The Application of Dependence Analysis to Software Architecture Descriptions

As the focus of software design shifts increasingly toward the architectural level, so too are its analysis techniques. Dependence analysis is one such technique that shows promise at this level. In this paper we briefly describe and illustrate the application of dependence analysis to architectural descriptions of software systems.

4th ICSE workshop on component-based software engineering: component certification and system prediction

This workshop brings together researchers from the areas of component trust and certification, component technology, and software architecture. The goal of this workshop is to ensure that work in the areas of certification of software components and architectural analysis for prediction of system quality attributes will be mutually aware, if not mutually reinforcing. The output of the workshop will be a defined set of community model problems that reflects this intersection of interests.

Achieving Agility through Architecture Visibility

L.L.Bean is a large retail organization whose development processes must be agile in order to allow rapid enhancement and maintenance of its technology infrastructure. Over the past decade L.L.Beans software code-base had become brittle and difficult to evolve. An effort was launched to identify and develop new approaches to software development that would enable ongoing agility to support the ever-increasing demands of a successful business. This paper recounts L.L.Beans effort in restructuring its code-base and adoption of process improvements that support an architecture-based agile approach to development, governance, and maintenance. Unlike traditional refactoring, this effort was guided by an architectural blueprint that was created in a Dependency Structure Matrix where the refactoring was first prototyped before being applied to the actual code base.

Ensembles: abstractions for a new class of design problem

Trends in component-based software development point to increased use of pre-existing or purchased components. A consequence of this type of development is that systems are being composed of large-grained components over which the developer wields little control. This and other issues related to the use of commercial components has created a new class of design problem that is not addressed by traditional development methods and tools. In this paper we describe this class of design problem, and introduce Ensemble, a conceptual language that supports assembling software systems from commercial components.

CMEH: Container Managed Exception Handling for Increased Assembly Robustness

Component containers provide a deployment environment for components in a component-based system. Containers supply a variety of services to the components that are deployed in them, such as persistence, enforcement of security policies and transaction management. Recently, containers have shown a large amount of potential for aiding in the predictable assembly of component-based systems. This paper describes an augmentation to the component container, called the Container-Managed Exception Handling (CMEH) Framework, which provides an effective means for deploying exception handling mini-components into a component-based system. This framework promotes a more effective handling of exceptional events, as well as a better separation of concerns, yielding a more robust component assembly.

WICSA Wiki WAN Party: capturing experience in software architecture best practices

Researchers, practitioners, educators, and students of software architecture would benefit from having online access to quality information about the state of research and practice of software architecture. In recent years, Wiki technology has enabled distributed and collaborative editing of content using only a Web browser. To explore whether Wiki technology would be effective in facilitating the ongoing discussion and evolution of ideas on software architecture, we hosted the WICSA Wiki WAN Party (WWWP) during the 4th Working IEEE/IFIP Conference on Software Architecture (WICSA 2004). We used a history tool developed at IBM Research to monitor site activity and provide daily feedback to conference participants. This report recounts experience hosting this Wiki site and summarizes the site activity.