Generating Aspect Code from Models

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Generating Aspect Code from Models
1Jeff Gray, 2Ted Bapty, 2Sandeep Neema,
2Aniruddha Gokhale, 2Balachandran
Natarajan 1University of Alabama at Birmingham
(UAB) 2Vanderbilt University/ISIS

• OOPSLA 2002 Workshop on Generative Techniques in
  the Context of the MDA
• November 5th, 2002
• Seattle, WA
• This work is supported by the DARPA IXO, under
  the Program Composition for Embedded Systems
  (PCES) program, Contract Number F33615-00-C-1695

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An argument for generating aspect code from models

• Often, generators have knowledge of pre-existing
  libraries of components
• Generation of glue code (high reuse) vs.
  generation of whole system (little reuse)
• If not originally templatized, component library
  can become closed to modification during
  generation
• Granularity of reuse at the interface level
  internal implementation of method bodies not open
  for change
• Customizing the component to monitor/adapt to QoS
  requirements specified in the model may not be
  possible
• An AOP approach could offer some benefit, whereby
  the points of customization are weaved into
  library components

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Concretizing aspects
AspectJ
Generated Concrete Aspects
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Component modeling in GME
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Two levels of weaving
Aspect Model Weaving
Aspect Code Weaving
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Abstract Component
public abstract class Component public
abstract void call_back() public abstract int
get_data() public abstract void init()
public abstract void data_retrieve() public
abstract void compute() public abstract void
notify_availability() protected int _data
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Stubbed LocDisplay library component
public class LocDisplay extends Component
public void call_back() System.out.println("T
his was LocDisplay.call_back") public int
get_data() return _data public void
init() public void data_retrieve()
System.out.println("This is LocDisplay.data_retrie
ve!") UpdateMap map new UpdateMap()
map.get_data() public void compute()
System.out.println("This is LocDisplay.compute!"
) public void notify_availability()
System.out.println("This is LocDisplay.notify_avai
lability!")
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Lazy abstract library aspect
abstract aspect Lazy abstract pointcut
call_back(Component c) abstract pointcut
get_data(Component c) after(Component
c) call_back(c) System.out.println("aft
ercall_back (Lazy)!") c.notify_availabilit
y() before(Component c)
get_data(c) System.out.println("beforeg
et_data (Lazy)!") c.data_retrieve()
c.compute()
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Generated code for concrete aspect
aspect LocDisplayLazy extends Lazy
pointcut call_back(Component c) this(c)
executions(void LocDisplay.call_back(..))
pointcut get_data(Component c) this(c)
executions(int
LocDisplay.get_data(..))