Testing Componentbased Software:

1
Testing Component-based Software

2
Outline

• Testing Component-based Software
• Precautions
• Adequate Testing of Component-based Software
• Adequate Testing Criteria

3
Component-based Software

• Construction
• Relatively advanced
• It is composed of components
• Modules ? encapsulate both data and functionality
• Testing
• Difficulties

4
Construction

• Logically-encapsulated code fragments
• Plug-ins, add-ins, Java applets
• Domain-specific frameworks
• Microsoft Foundation Classes
• Infrastructure technologies
• CORBA, ActiveX and JavaBeans
• Compound document
• OLE and OpenDoc

5
Advantages

• Require less time to specify, design, test, and
  maintain, yet satisfy the high reliability
  requirements
• Write once, reuse in many systems
• Are plug-and-play, easy to integrate

6
Reusing components developed for a different
project

• Changing priorities between applications
• Components can be used under very different
  context
• Necessary to test components in their new
  environments

7
Using components developed for multiple users

• Write once, but require more testing
• Necessary modification of code to adapt new
  environment
• If the source code is unavailable
• Significantly more difficult for testing
• Impossible for modification

8
COTS components

• Lack of source code
• Lack of detailed knowledge
• No control over the components maintenance and
  support
• Contains unnecessary functionality
• Interoperability problems, performances
• Vendor goes out of business?

9
Solutions

• Easy to identify and access of
• Specification
• Requirements and implementations
• Source code and built
• Test suite, and pointers to specification
• Primary maintainer
• Stable interface

10
Determine Test Adequacy

• Sequential composition
• Anticomposition
• Antidecomposition
• Can we do something more?

11
C-adequate

• Given an applicable subdomain-based criterion C,
  a program P, and a component M
• A test set TP TM is C-adequate if it
  contains at least one test case from each
  subdomain in SDc( DP DM )

12
C-adequate-for-P

• P-relevant subset of DM is the set of all inputs
  of Ms access method that execution of P causes
  some methods of M execute
• A test set TM is C-adequate-for-P if TM contains
  at least one test case from each subdomain in
  SDc(P-relevant(DM))

13
C-adequate ! C-adequate-for-P

• There exist a program P, a component M of P, a
  criterion C, and a test set TM for M such that TM
  is C-adequate but not C-adequate-for-P
• such that TM is C-adequate-for-P but not
  C-adequate

14
C-adequate-on-M

• A test set TP is C-adequate-on-M if TP traverses
  M with at least one element from each subdomain
  in SDc(P-relevant(DM))

15
C-adequate ! C-adequate-on-M

• There exist a program P, a component M of P, a
  criterion CP and CM, and a test set TP for P such
  that TP is CP-adequate but not CM-adequate-on-M
• such that TP is CM-adequate-on-M but not
  CP-adequate

16
Applications

• Unit-testing of a component
• C-adequate-for-P
• Integration-testing of compositions of components
• C-adequate-on-M