Component Mining

1
Component Mining

• Mahdi Cheraghchi-Bashi-Astaneh
• cheraghchi_at_ce.sharif.edu

2
Outline

• What is a component?
• Software reuse
• What is component retrieval?
• Pros and cons of reuse
• How to retrieve?
• Evaluation

3
What is a component?

• A part of the whole.
• A piece of software small enough to create and
  maintain, big enough to deploy and support, and
  with standard interfaces for interoperability" -
  Jed Harris, President CI Labs.
• Self contained binary pieces of software, but not
  complete applications.
• Can be combined with other components to produce
  complete applications, regardless of the
  languages the components are implemented in or
  platforms they run on.
• Object-Oriented methods are often used for
  component development and reuse.

4
Some Examples in Practice

• Borland Delphi
• Borland C Builder
• Borland Kylix
• OLE / COM / ActiveX
• JavaBeans
• CORBA

5
Software Reuse

• Software reuse is the process of creating
  software systems from existing software rather
  than building software systems from scratch.
  Krueger,1992
• Levels of software reuse source code,
  algorithms, architectures, domain models, design,
  program transformations, documentation, every
  possible aspect of a software system

6
What is Component Retrieval?

• The mere existence of a component library does
  not automatically entail its re-use.
• Component Mining is the deliberate, organized
  and automated process of extracting reusable
  components from an existing rich software base.
• Re-users need support to help them identifying
  components which suit their needs, This task is
  the topic of software component retrieval.
• The goal is to develop reusable, adaptable
  software components rather than large, monolithic
  applications.

7
Types of Reuse

• Black-Box Reuse a client may reuse the retrieved
  components as is.
• Component-adaptive Grey-Box Reuse a client may
  reuse the retrieved components without meeting
  any additional conditions but only after
  interface-level modifications of the components.
• White-Box Reuse arbitrary additions and
  modifications are required.

8
Pros and Cons of Reuse

• Advantages
• Reduces time and cost spent on programming.
• Increases programmers productivity.
• Increases program quality and reliability.
• Expertise sharing
• Problems
• It is hard to find things, especially in a large
  scale.
• Typically components are not (easily) modifiable.
• It is hard to manage a large pool of components.
• It only worth if it is easier to locate and
  modify a reusable component than to write it from
  scratch.

9
How to Retrieve?

• Component retrieval is in fact a form of
  information retrieval. Despite this fact,
  dedicated component retrieval algorithms are
  being developed, since software is more than an
  ordinary text.
• Component retrieval is a complex and heuristic
  process.
• Typically needs a well-structured repository of
  components.
• Methods of retrieval
• Algorithms based on the meta-data accompanying
  software components.
• Algorithms based on the structure of the
  components.
• Exact retrieval versus approximated retrieval

10
Retrieval by Meta-Data

• By meta-data we mean the documentation
  accompanying the component.
• This method relies on existence and quality of
  the documentation and needs some pre-processing.
• How to find?
• Using full-text search on documents and program
  files No cost, but inaccurate
• By classification of the components either
  automatically or manually. (depending on the cost
  and accuracy we need)

11
Retrieval by Structure

• Depends on the availability of the structure in
  some form (source code, interface, etc)
• Depends on the availability of computer language
  processors.

12
Some Other Methods

• Formal component specification
• Domain theories algebraic model, signatures, etc
• Interface specifications
• Interface matching (automated theorem proving,
  etc)
• Semantic Classification
• Feature-based methods (What possible features can
  a component have?)

13
Some Other Methods

• Deduction-Based Component Retrieval
• Is the only method which retrieves proven matches
  only.
• Suitable for the development of high-reliability
  or safety-critical applications, e.g. space craft
  control systems.

14
Searching and Browsing

• Searching Software developers formulate a query,
  and the repository system returns components that
  match the query.
• Problem Formulating an effective query is a
  challenging task.
• Browsing Developers determine the relevance of
  the components currently being displayed in terms
  of their development task, and traverse the
  associated links.
• It is an incremental task, and is usually
  preferred.
• Problem Software developer may be puzzled.
• Context-Aware Browsing Infers developers tasks
  by monitoring their interactions with the
  environment.
• Similar to browsing, but results in a
  significantly smaller browsing space.
• Uses learning methods to refine itself.
• Problem It is difficult to understand the
  content.

15
The Reuse Environment

• A component database.
• A library management system providing access to
  the database.
• A software component retrieval system (e.g. an
  ORB) that enables client applications to retrieve
  components from the library server.
• CBSE tools that support the integration of reused
  components into a new design.

16
Evaluation Measures

• Recall Ratio of the number of relevant
  components retrieved to the total number of
  relevant components in repository
• Precision Ratio of the number of relevant
  components retrieved to the total number of
  components retrieved
• Response time

17
Summary and Conclusion

• Software reuse is a crucial concern in todays
  world of complex software products.
• Component-based development model plays an
  important role in software reuse.
• Component-based model is useful only when an
  satisfactory means of retrieval is available.
• No definite answer has yet been developed for
  description of components in unambiguous
  classifiable terms.
• Component retrieval is a difficult problem and
  more work is needed to find an efficient solution.

18
References

• D. Spinellis, K. Raptis, Component Mining a
  process and its pattern language, Information and
  Software Technology 42 (2000) pp 609-617
• Hafedh Mili et al, An experiment in software
  component retrieval, Information and Software
  Technology 45 (2003) pp 633-649
• K. McArthur et al, An evaluation of the impact of
  component-based architectures on software
  reusability, Information and Software Technology
  44 (2002) pp 351-359
• P.A.V. Hall, Architecture-driven component reuse,
  Information and Software Technology 41 (1999) pp
  963-968
• I. Crnkovic, M. Larsson, Challenges of
  component-based development, The Journal of
  Systems and Software 61 (2002) pp 201-212
• Y. Ye, G. Fischer, Context-Aware Browsing of
  Large Component Repositories, IEEE 16th
  International Conference on Automated Software
  Engineering, 2001
• A. M. Zaremski, J. M. Wing, Signature Matching, A
  Key to Reuse
• B. Fischer, Deduction-Based Software Component
  Retrieval (Thesis)