Managing the Object Soup in Ambient-Oriented Applications

This deck summarizes my master's thesis and was presented at the final defense in September 2012.

Transcript

1. MANAGING THE OBJECT SOUP IN AMBIENT-ORIENTED APPLICATIONS NICK DE COOMAN
2. 2 Life More and More Mobile Mobile ad hoc networks No shared infrastructure Volatile connections Dynamic network topology
3. 3 WeScribble
4. 3 WeScribble
5. 3 WeScribble
6. 4 Functional Requirements for WeScribble 1 2 Remote drawers can only read the properties of a shape, not change it. A shape can be temporary owned by one drawer at a time and this only for a limited duration.
7. 5 In this Thesis... We propose software abstractions to organize the object reference soup
8. 5 In this Thesis... We propose software abstractions to organize the object reference soup
9. 6 Aliasing Behavioral Protocol actor actor
10. 6 Aliasing Behavioral Protocol actor actor def a := object: { ... }
11. 6 Aliasing Behavioral Protocol actor actor uponDefiningPrincipal Protocol def a := object: { ... }
12. 6 Aliasing Behavioral Protocol actor actor uponDefiningPrincipal Protocol def a := object: { ... }
13. 6 Aliasing Behavioral Protocol actor actor uponDefiningPrincipal Protocol A
14. 6 Aliasing Behavioral Protocol actor actor uponDefiningPrincipal Protocol A def b := a
15. 6 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponDefiningPrincipal Protocol A def b := a
16. 6 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponDefiningPrincipal Protocol A B
17. 6 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponDefiningPrincipal Protocol A B def addShape(arg){...}; addShape(a)
18. 6 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A B def addShape(arg){...}; addShape(a)
19. 6 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A B ARG
20. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A B ARG
21. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A
22. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A when: ServiceTag discovered: { |c| ... } remote reference acquired C
23. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponDefiningPrincipal Protocol A when: ServiceTag discovered: { |c| ... } C
24. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponDefiningPrincipal Protocol A when: ServiceTag discovered: { |c| ... } C
25. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponDefiningPrincipal Protocol A when: ServiceTag discovered: { |c| ... } C
26. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponDefiningPrincipal Protocol A C
27. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponDefiningPrincipal Protocol A def d := c C D
28. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponBindingRemoteAlias uponDefiningPrincipal Protocol A C D
29. 7 Aliasing Behavioral Protocol actor actor uponBindingLocalAlias uponLocalAliasing uponRemoteAliasing uponBindingRemoteAlias uponDefiningPrincipal Protocol A Receiving remote reference = acquiring remote reference + resolving remote reference C D
30. Aliasing Behavioral Protocol at Work 8 Distributed object graph inspector Ownership Domains CASE STUDY 1 CASE STUDY 2
31. Typestate-oriented Programming 9 10 Aliasing behavioral protocol alone is insufficient to organize the object soup
32. Chameleon Objects 10 Typestate-oriented programming for ambient-oriented applications remote reference local reference transition()
33. Chameleon Objects 10 Typestate-oriented programming for ambient-oriented applications remote reference local reference transition()
34. Chameleon Objects Typestate-oriented programming for ambient-oriented applications remote reference local reference 11 transition()
35. Ownership Type Tags 12 Out of the box aliasing strategies Aliasing behavioral protocol + Chameleon objects LOCAL READONLY UNIQUE
36. 13 Local Ownership Type Tag Bob Alice local object ✕ messages disallowed remote client object def raiseError := { raise: XIllegalOperation.new("Cannot expose remote alias") }; def uponRemoteAliasing(localProxy, aliasReceiver, remoteAlias){ raiseError() }; def uponBindingRemoteAlias(localProxy, aliasReceiver, fieldObj, remoteAlias){ raiseError() }; LOCAL
37. 14 ReadOnly Ownership Type Tag Bob Alice local object only read messages remote client object READONLY
38. 15 Unique Ownership Type Tag Waiting Released Expired Acquired Eve Bob Alice UNIQUE remote client object acquired waiting expired
39. 16 WeScribble def makeShape(color, position, size){ def shape := object: { def getShapeData(){ [position, color, size] }; def changeColor(newColor){ color := newColor }; def reposition(newPosition){ position := newPosition }; def becomeTemporaryOwner(){ temporaryOwned }; def remove(){ ... }; } taggedAs: [ReadOnly]; def temporaryOwned := object: { def changeColor(newColor){ shape.changeColor(newColor) }; def reposition(newPosition){ shape.reposition(newPosition); } } taggedAs: [Unique]; export: shape as: ShapeObj; shape } READONLY SHAPE shape temporaryOwned UNIQUE
40. 17 Conclusion LOCAL READONLY UNIQUE Ownership Type Tags Chameleon Objects Aliasing Behavioral Protocol
41. 18 Research Training Promoter Prof. Dr. Wolfgang De Meuter Elisa Gonzalez Boix - Christophe Scholliers Advisors
42. 18 Research Training Promoter Prof. Dr. Wolfgang De Meuter Elisa Gonzalez Boix - Christophe Scholliers Advisors http://sites.google.com/site/nickdecooman
43. 19 Related Work
44. 19 Related Work Alias Detection
45. 19 Related Work Alias Advertisement
46. 19 Related Work Alias Prevention
47. 19 Related Work Alias Control
48. Typechecking Chameleon Objects 20 def obj := chameleonObject: { | install | def state1 := object: { def change(){ toState2() }; def foo(){ n()+2 }; }; def state2 := object: { def change(a){ foobar(bar(a)) }; def bar(b){ 9 }; }; def foobar(z){ toState1(z) }; def toState1(a){ install(state1) }; def toState2(){ install(state2) }; def n(){ 22 }; toState1(n()) }; obj.foo(); obj.change(); obj.bar(7); obj.change(33); state2 state1 change change BODY toState2 foobar toState1
49. Dynamically Tagged Objects 21 Chameleon object should obtain type tags of the current state def obj := dynamicallyTaggedObject: { ... }; tag: obj as: [TypeTag1, TypeTag2]; when: obj isTaggedAs: TypeTag1 do: { ... };
50. 22 Conclusion LOCAL READONLY UNIQUE Ownership Type Tags Chameleon Objects Aliasing Behavioral Protocol