Due Date: 12/10/01

Course Title: Application Servers Course Number: g22.3033-011

Instructor: Jean-Claude Franchitti Session: 12

1. Ongoing Project Background

This homework follows the course on-going project approach described in the homework #1 specification. You should keep enriching your framework-based enterprise application design, and take advantage of the application server platforms used to implement/deploy your application. Your application should be developed in such a way as to be shielded as much as possible from the underlying software infrastructure. For that reason, it is a good idea to build your applications around a portable application framework. As portability issues arise, you will learn how to improve the design of your applications to make them more portable across application server platforms.

2. Web Services Computing Environments

A “Web Service” is an interface that describes a collection of operations that are network accessible through standardized XML messaging.

In this homework, you will experiment with a Web Services platform in the context of the framework-based application developed as part of previous assignments on top of the CORBA and J2EE Component-Based Computing Environments. You may wish to extend the application(s) you developed so far to motivate the need for migration to a Web Services platform as a way to handle flexible access to your application components in a service-trading environment.

2.1. Software Infrastructure Provided:

Programming environment

1. CORBA and EJB MOO Frameworks used in previous homework

2. Other development tools best suited for Web Services development environments. No particular Web Services platform is imposed for this homework. However, it is suggested to look at Microsoft .Net or IBM Alphaworks’ WSTK. Information on IBM’s WSTK is available at http://www.alphaworks.ibm.com/tech/webservicestoolkit, and related information can be found at http://xml.coverpages.org/ni2001-02-19-b.html.

3. No additional application software is provided for this homework.

Additional Sample Applications

1. No additional sample applications are provided for this homework. You may wish to refer to the sample application provided by your Web Services platform.

3. Questions

1. Preparation phase:

Select a technology infrastructure that is compatible with the application infrastructure required for this homework.
Install the application infrastructure software, and experiment with it.
Experiment with the sample application on the selected platforms.
Refine your framework-based enterprise application and extend it to make use of a Web Services platform. Your application should involve Web Services deployed on at least two different DOC platforms. You should bear in mind that your application services are implemented as services on top of a community chat framework. The resulting architecture should provide a similar level of functionality with improved accessibility. If your application is well designed you should simply have to extend existing services or create separate services that extend the semantics of your application. You may wish to keep using a combination of infrastructure frameworks for the time being.

2. Prepare a short report documenting your refined framework-based enterprise application (using software engineering standards), and explaining its motivation.

3. Prepare a short report including functional diagrams and screenshots (as needed) to demonstrate your understanding of the infrastructure software. Explain the infrastructure software differences between the application you developed in previous assignments and the one you are developing for this homework.

4. Develop and deploy your framework-based enterprise application as follows on top of a Web Services platform. You are welcome to either reuse services provided by the sample application or complement them. Document the benefits and deficiencies of the approach on which Web Services environments are based and explain (as needed) how it limits your ability to develop the various application components you have envisioned for your enterprise application. Note that you do not need to provide a complete implementation of your application in this homework. You should restrict yourself to what you feel is feasible based on time and the level of support provided by the infrastructure software. Your application should be tuned for efficiency as allowed by the underlying infrastructure software, and you should document your performance engineering approach. You should conclude your report by suggesting, and implementing (as time allows) an improved Application Server model.

5. Explain how you would refine the “analyzer” tool you have been working on to capture information about applications deployed in previous assignments, and re-deploy them as XML-based applications such as: (a) the “SpyWeb” applications provided as support material under demo programs on the course Web site, (b) applications based on the Cocoon 2 XSP framework, and (c) Web Services. Note that the target application should again maintain a strict separation between content, style, and logic. As for previous assignments, your analyzer should strive to extract and represent a generic model of your application using a suitable markup language. You should also revisit the comments you made in homework 7 about Sygel’s “Wonder Machine”, and provide a detailed assessment of the added value of an analyzer-based Model Driven Architecture (MDA) as it compares to Microsoft .NET and Sun ONE.

6. Extra Credit: Implement a prototype of the analyzer tool described in question 5 (ongoing)

5. Deliverables

Please provide an electronic copy of your homework submission as one zip archive by sending it to the course TA by the beginning of next class. The archive should include your application software, any modified infrastructure software, a readme file describing the environment setup required to run your application, and your homework report (in word or text format). You should name your archive using the following convention for all homework archives: name_hw?_fa01.zip, where name may include additional underscore characters as needed. You are also required to provide a hard copy of your homework reports at the beginning of each session or according to the homework submission scheduled spelled out in the homework specification.

6. Grading

All assignments are graded on a maximum scale of 10 points. Your grade will be based equally on:

a. The overall quality of your documentation.

b. The understanding and appropriate use of application server related technologies.

c. Your ability to submit working and well-commented code.

d. Extra credit may be granted for solutions that are particularly creative.

7. Additional Information

Please let the TA know as soon as possible about teaming arrangements. You will need to stay with the same team for the duration of the course. You should only submit one report/archive per team for each assignment. To balance things out, the final grading in the course will take into account the fact that you are working as a team instead of individually, so you should feel free to work individually as well. Note that the final take home examination will require individual work.