Objects and Aspects: Wrapup

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Objects and AspectsWrap-up

• 15-819
• Jonathan Aldrich

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Object Mechanisms

• Prototypes
• Dynamic inheritance
• Multiple dispatch/pattern matching
• Overrideable fields
• Parameterized module systems
• Mixin inheritance

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Type Mechanisms

• Row polymorphism
• Family polymorphism
• F-bounded polymorphism
• Nested inheritance
• Abstract types
• Variance annotations
• Typestate
• Ownership

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Aspect Mechanisms

• Open classes
• Advice
• Pointcuts
• Aspect binding
• Dynamic deployment
• Class composition

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Analysis and Verification

• Typestate for objects
• Data groups
• Boogie
• Aspect-aware interfaces
• Open modules
• Model checking aspects

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Empirical Studies

• Comparing AspectJ and Hyper/J
• WebSphere
• AOP can implement homogenous concerns more
  consistently
• AOP can effectively isolate optional concerns
• AspectC
• Preliminary evidence that modular concerns can
  aid evolution

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Themes Declarativity

• Prototypes
• Dynamic inheritance
• Multiple dispatch
• Pattern matching
• Pointcuts
• Dynamic deployment

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Themes Extensibility

• In-place
• Open classes
• Advice
• Functional
• Parameterized modules
• Mix-in inheritance
• Overrideable fields
• Class composition
• Aspect binding

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Big Challenges

• Using aspects in evolving programs
• Useable symmetric AOP
• Effective AOP tool support
• Developing AOP constructs that are more modular
  and/or less brittle
• Cleanly combining functional and in-place
  extension
• Unifying mechanisms without complexity explosion
• Lightweight but powerful AOP/OOP type systems
• Verification methodologies that respect object
  and aspect paradigms