An Infrastructure for the Rapid Development of XML-based

Architecture Description Languages

[Dashofy-Hoek-Taylor02]

Presented by Ares SaldanaMarch 11, 2008

What is the Problem?

•Many and many ADL keep emerging.

•No real unification nor consensus of what and ADL should consist of

•Architects write their own ADL to accommodate their domain.

What is the Solution?

• An XML-based infrastructure for the rapid development of ADLs

• It consists of:

1. “an XML-based modular extension mechanism for rapidly developing new ADLs

2. a base set of features that can be reused in ADL development and

3. a flexibler set of tools to support ADL evelopment and use”

Other considerations

•Importance of Support Tools

•Enforcement of semantic consistency with ADL not provided

Characteristics

•Scalability

•Adaptability and Extensibility

•Concept Capture

Architectural Emphasis

•Distributed Architectures

•Integrating Architectures

•Dynamic Architectures

•Product Line Architectures

Justification

•Most ADLs are monolithic

•Changes are not easy

•Tool support

•Cost

XML

•Broad support from standard bodies. (W3C)

•Compatibility

•Suitable for developing modular and extensible notations.

Approach

•XML-based language to describe ADLs

•A base set of schemas

•A flexible tool support

XML Schemas and Extensibility

•Hybrid DTD

•XML Schema standard

•Each Module as a Schema

XLM and ADLs

•XML does not guarantee syntactic compatibility between modules.

•A get-a-way solution for this is Artificial Dependencies. However this reduces orthogonality.

•XML cannot describe semantics, by this requiring Semantically-aware tools.

xADL v 2.0

•Collection of schemas

•Very general. Do NOT describe behavior

•but can be specified using extension schemas

Characteristics of a xADL derived ADL

•Separation of run-time and design-time models of a software system.•Implementation mappings that map the ADL specification of an architecture onto executable code•The ability to model aspects of architectural evolution and product line architectures.

INSTANCES or xArch

•Constructs while modeling Run-Time architectures.

• Component Instances

• Connector Instances

• Interface Instances

• Link Instances

• Sub-architectures

• General Groups

Structure and Types Schema

• Components

• Connectors

• Interfaces

• Sub-architectures

• Links

• General Groups

• Component Types

• Connector types

• interface types

Advantages

•Typing

•Allows the architect to reason about similarities among elements of the same type.

•Run and Design-time can be extended separately

Implementation

Mappings•Not platform specific•Where but not what data location

•xADL Abstract Implementation Schema

Modeling Architectural EvolutionEvolution and Product

Lines

•Versions

•Options

•Variants

Tool Support

•Provide parsing, syntax checking, and syntax-directed editing based on ADL schemas.

•XML Spy

•Apache Xerces

•Apigen

•xArchADT

•ArchEdit

Real World Experience

•AWACS

•JPL

•MAppings to Koala & Mae

Related Work

•Traditional and Domain-Specific ADLs

•XML-based ADLs

•UML

Conclusions

•Infrastructure for developing ADLs with reduced effort and time.

•No parsers, allowing to address other problems (research)

“Future” work

•ArchDiff - To see the differences between two architectures

•Investigate Issues related to distributed, dynamic software architectures, as well as applying architecture-based development to areas of the life-cycle such as deployment and maintenance

Thank you

•Questions?