Analysing Object Oriented Framework Reuse using Concept Analysis

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Analysing Object Oriented Framework Reuse using
Concept Analysis

• Gabriela Arévalo
• SCG - University of Bern
• Tom Mens
• PROG Lab - Vrije Universiteit Brussels
• ECOOP 2002 Inheritance Workshop

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Understanding an object oriented inheritance
hierarchy

• Behaviour and structure reuse
• Interface and Inheritance relationships
• Problems
• number of classes is large
• inheritance hierarchy is deep
• Use of Concept Analysis groups of elements
  based on their properties

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Example

• B and C have a similar structure

• B and C calls m3 defined in A via a super

• B and C define m2 and m4 ( abstract in A)

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Use of Concept Analysis
A

• Groups of elements based on their properties
• Experiments
• Elements selector called in class
• Properties
• Selector called via a self super
• Implementor class concrete abstract
• Sender and implementor ancestor descendant
  internal
• Analysis of Magnitude hierarchy

m1 ... ... self m2
B
m2 ... m3 ... ... super m1 ...
self m3
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Pattern 1 Self send captured in the same class

• expanded, depth, parent
• Called via self in class AssocTreeWithParent
• Concrete implementation
• Sender and implementor are the same class
• Internal interface
• Class-specific behavior

AssocTreeWithParent
expanded ltconcretegt depth ltconcretegt parent
ltconcretegt ... self expanded ... self
depth ... self parent
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Pattern 5 Self send captured locally with super
delegation

• ?, ?
• Called via self and super in class SmallInteger
• Concrete implementation in Magnitude and
  SmallInteger
• Sender and implementor are the same class and an
  ancestor
• Delegation between methods in the same class and
  with the superclass

Magnitude
? ltconcretegt ? ltconcretegt
SmallInteger

• ? super ?
• super ?
• ... self ?
• ... self ?

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Pattern 6 Template and hook methods

• digitAt, digitLength
• Called via self in Integer
• Abstract implementation in Integer
• Concrete implementation in SInteger and LInteger
• Sender and implementor are the same class and an
  descendant

Integer
digitAt ltabstractgt digitLength
ltabstractgt ... self digitAt ... ... self
digitLength

• Hot spots Template and hook methods

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Conclusions Future Work

• Concept patterns identify non-documented
  relationships about how classes and methods are
  reused
• Provide guidelines on how an object oriented
  frmwk can be customized or reused
• Detect different types of inheritance interface
  implementation
• Identify potential impact of changes to framework
  classes
• Identify opportunities for refactoring