359D 16107 Eric Wohlstadter

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359D 16/1/07 Eric Wohlstadter

• What is Middleware?
• What is Aspect-Oriented Programming?
• Introductions
• Course Format
• Discussions
• Assignments

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What is Middleware?

• Mediates heterogeneities (differences)
• Defines standard protocols for distributed
  computing
• Abstracts details of using protocols
• Programmers use abstractions
• Objects, Web Services, Broadcast channels
• Abstractions implement protocols
• Provided as off-the-shelf software
• Not traditionally integrated in the operating
  system or a virtual machine

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Problems with Distribution
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Common Middleware Platforms

• Object-oriented
• CORBA, Java RMI
• Container-based
• J2EE, .NET
• Aspect-Oriented
• Spring Framework
• Message-oriented
• TIBCO, JMS
• Web Services
• REST, SOAP
• Web Frameworks
• Struts, PHP, AJAX

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Middleware

• Conclusion
• Middleware is about creating a run-time
  environment that mediates interactions between
  programming abstractions
• We will come back to the details in a few weeks
• First we will focus on AOP

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AOP Conceptual Level

• Give programmers the power to implement the
  environment in which objects interact
• Behavior of objects depends on their context
• Override the behavior of method calls based on
  the context where the call takes place
• Context
• Implemented using pointcuts
• Method call behavior
• Implemented using advice

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OO vs. AOP

• Use OO to give different classes different
  behaviors
• Use AOP to give interactions different behaviors

A
A
B
B
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OO vs. AOP

• Use OO to give different classes different
  behaviors
• Use AOP to give interactions different behaviors
• Example
• All interactions between A and B are access
  control mediated

A
A
B
B
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Examples of Contexts

• Calling or Callee class
• Calling or Callee method
• Methods active on the call stack
• Argument or Return types of methods
• Write a query that captures a context of interest
  using a pointcut!

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AOP

• Go to AOP pdf

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AOP and Middleware

• So, AOP provides support for focusing on
  interactions
• Helps us to create new middleware features
• See how AOP is used to address distributed
  programming concerns
• RPC, Security, Fault-tolerance, Management
• AOP used this way by companies such as IBM,
  Siemens, Spring
• Compare to traditional middleware
• J2EE, .NET, CORBA, Web Services

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International Conference on AOSD

• Sixth Aspect-Oriented Software Development
  Conference
• Sheraton Wall Centre (on Burrard)
• Variety of tutorials, workshops, demos and
  presentations
• Several middleware related
• March 12-16
• No class that week
• Check out www.aosd.net/2007

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Introduce Yourself

• Name
• Degree objective/Year
• Research Interest or Career Objective

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Course Format

• Usually two research papers per class
• Some lectures and tutorials
• Paper review for one of the two papers
• Each paper will be presented by students by
  informal slide presentations
• Class discussion is important (10 of mark)
• Throughout the term students are required to
  complete a research project
• No exams

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Research Project

• Related to a topic in Middleware and/or AOP
• Individually or group of two students
• Recommendation
• writingThesis(student) ? inGroup(student)
• writingThesis(student) ? inGroup(student)
• gt 2 page proposal (Feb 8th)
• gt 4 page paper and implementation
• 10-15 minute (10 mins per person) class
  presentation at the end of the term

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Research Project Scope

• Implement original (software) feature or feature
  described in a research paper
• possible A
• Implement useful feature or describe an original
  feature without implementing
• possible B
• Review existing research literature or technical
  description of existing systems
• possible C

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Paper Reviews

• Between 3/4 and 1 page.
• Reviews will be marked out of 10 points
• Reviews will be marked and returned in three
  batches
• Review should be in paragraph form (not bulleted
  list)
• Recommend you address these four questions (next
  slide)

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Questions

• What is the problem addressed by this paper?
• What is the approach to solve this problem?
• How do the authors validate (prove/show/argue)
  that their approach solves the problem?
• What is one part of the approach or validation
  that you think can be improved or extended?

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Paper Presentations

• Two students will present a paper each class
• Recommend use of slides
• You may use slides which may be available on the
  web
• You may copy figures from document to use in
  slides
• You must reference all outside materials used
• 15 minutes
• Summarize paper and address the 4 questions

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Attendance

• Attendance is required
• Participation in discussion is 10 of mark
• You will not be able to submit paper reviews for
  classes which you did not attend
• Exceptions will be made for students with
  documented medical excuses or academic related
  travel obligations

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Grading

• Project proposal 10
• Implementation and Report 30
• Project Presentation 30
• Paper reviews 20
• Class participation 10

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Conclusion

• Questions?
• Thursday
• Gregor Kiczales, Erik Hilsdale, Jim Hugunin, Mik
  Kersten, Jeffrey Palm, and William G. Griswold.
  An overview of AspectJ. ECOOP 2001.
• AspectJ in class tutorial
• Bring your laptops with latest Eclipse installed
• Course Web Page
• http//www.cs.ubc.ca/wohlstad/539D.html