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Developing your campus portal

What kind of Java expertise is necessary to develop a campus portal using uPortal?

In general, to use the uPortal framework to develop a campus portal (the "instance" of the portal for use with your application server), over and above the level of expertise necessary to administer your application server (see above), you must be an experienced Java programmer, familiar with the JDK 1.2 tools for compiling, packaging, deploying and running server-side Java programs, and conversant with most of the technologies that comprise the J2EE specification. Specifically, at a minimum, you must have experience with:

  • XML. The uPortal framework uses XML and XSLT extensively to ensure the platform independence of data and to separate that data from it's presentation. To develop a portal with uPortal, you will have to create/edit XML files and create/edit XSL stylesheets. If you're not fluent with the XML-related APIs in Java, (McLaughlin2000) provides a comprehensive tutorial on writing Java programs that can create and manipulate XML documents. The uPortal developers highly recommend (Kay2000) to those looking for a tutorial and in-depth reference guide to XSLT. (Bradley2000) provides a guide to the overall XSL standard.
  • JSP: The portal framework uses Java Server Pages to facilitate the intermixing of markup language code required by a web browser and programming language code that leverages the underlying Java Runtime environment. If you want to change the look and feel of the portal substantially, you'll have to edit Java Server Pages, so you should understand how to use JSP syntax correctly. For those looking for a tutorial on JSP, (Manning) is an excellent choice.
  • Servlets. JSP works as an abstraction layer on top of the Java Servlets API and because of this, experience writing servlets will come in handy. Several programming 'idioms' in the portal code originated with Servlet programming. Although now a little dated, (Hunter1998) is a great tutorial on Java Servlets. The publisher expects to release a new edition soon.
  • SQL. The portal requires the use of a relational database to store some user, authentication, and channel subscription information, and the standard way to issue requests to a relational database server is using SQL, the Structured Query Language. You must therefore be familiar with the syntax and proper use of SQL in order to work with the uPortal framework. (Gulutzan1999) offers comprehensive coverage of the SQL standard. I say these are minimums because if you want to deliver something over and above the minimum functionality (for example authenticating via an LDAP server) then you'll have to be familiar with other J2EE technologies and/or APIs (for example, JNDI).

You keep writing that uPortal is a framework. Isn't that just an empty yuppie marketing word?

No. I'm using the word 'framework' in its widely-accepted, Software Engineering sense (Wirfs-Brock1991). A framework is a reusable design, expressed as a set of classes, that can serve as a solution to a family of related problems and support reuse at a larger granularity than classes. A mature framework allows components to be reusedas "black boxes", that is, a programmer can incorporate them into a system under construction without knowing their implementations (Johnson1998). Most frameworks in widespread use today are for constructing graphical user interfaces (GUIs) for traditional desktop applications. uPortal is different in that it's a framework for developing a web portal and developing content for display within that portal, but the underlying principal of both kinds of frameworks is the same: the framework provides programmers with an infrastructure that supports a coherent architectural model, allowing developers to concentrate on applying their expertise to the problem domain. In the case of uPortal, the framework takes care of the common functionality that every portal needs, so that you can implement the parts that are important and specific to your campus.

Developing content and applications for use with uPortal

What kind of experience is necessary to develop content and/or applciations for use with uPortal?

It depends upon what kind of content you want to deliver through the portal. For simplest content provision, you only have to know how to produce an html document. One of the defined kinds of channels for use with uPortal is an RSS (RichSite Summary) channel, the same format that Netscape uses for their Internet portal. If you create an XML document which adheres to this standard , the uPortal framework will handle formatting and presenting the output for you. To deliver content which requires complex user interaction, you'll have to create a complete web application which uses a channel as its user interface. This approach requires that you have the XML, Servlets and SQL skills that someone developing a campus portal instance using uPortal has (see above) as well as experience with:

  • JDBC. It's likely you will want your application to store information in and retrieve information from a database, so the ability to use the Java Database Connectivity API will be essential. The portal itself requires a relational database to store information related to users and their preferences, and the standard way for your application to access this information is by using JDBC. If you're not familiar with the JDBC API, (White1999) is a comprehensive tutorial, reference and source of sample code.
  • EJB. If your application requires distributed data access, transactions and persistence, the Enterprise Java Beans distributed component model will probably become an important part of your architecture. For EJB beginners, (Monson-Haefel2000) provides a complete reference. To get an idea of what you're in for when you begin developing channnels, carefully read Michael Oltz' tutorial.

My university has a large number of legacy applications that we want to provide access to from the portal. Can I do this?

Maybe. It depends upon the application. Did you write the application (and have the source code) or did you purchase a binary package from a vendor? If you have the source code, its relatively easy to create an alternate user interface to the application that operates within the portal. in uPortal parlance, this would be called a "channel". Your channel would display itself to the user in the portal and feed the input from that user to your application. Your legacy application would then process the data and send the output back to the channel, and the channel would in turn display the results to the user inside the portal.

If you purchased an application from a vendor, things are a bit more complicated, but the high-level approach is the same. You'd have to write an adaptor that would wrap the output of the legacy application in XML so that it can be displayed inside the portal. When you have this, you can then write a channel for use with the portal that interacts with your adaptor and actually facilitates the translation of the XML so that the portal can display it.

Appendix

References

Books

[1] [Bradley2000] Neil Bradley. Copyright © 2000 Neil Bradley. 0-201-67487-4.
The XSL Companion. Addison-Wesley Publishing Company.

[2] [Gulutzan1999] Peter Gulutzan1999 and Trudy Pelzer. Copyright © 1999. 0-879-30568-1.

SQL-99 Complete, Really. CMP Books.

[3] [Harold1999] Elliotte Rusty Harold. Copyright © 1999. 0-764532-36-7.
XML Bible. IDG Books.

[4] [Hunter1998] Jason Hunter and William Crawford. Copyright © 1998. 1-565923-91-X.
Java Servlet Programming. O'Reilly & Associates.

[5] [Kay2000] Michael Kay. Copyright © 2000 Wrox Press. 1-861003-12-9.

XSLT Programmer's Reference. Wrox Press.

[6] [Fields2000] Duane K. Fields and Mark A. Kolb. Copyright © 2000.1-884777-99-6.
Web Development with JavaServer Pages. Manning Publications Company.

[7] [McLaughlin2000] Brett McLaughlin. Copyright © 2000 O'Reilly & Associates.0-596-00016-2.
Java and XML. O'Reilly & Associates.

[8] [Maruyama1999] Hiroshi Maruyama, Kento Tamura, and Naohiko Uramoto. Copyright © 1999. 0-201-48543-5.
XML and Java : Developing Web Applications. Addison-Wesley Publishing Company.

[9] [Monson-Haefel2000] Richard Monson-Haefel. Copyright © 2000 O'Reilly & Associates. 1-56592-869-5.
Enterprise JavaBeans. O'Reilly & Associates.

[10] [White1999] Seth White, Maydene Fisher, Rick Cattell, and Graham Hamilton.
Copyright © 1999. 0-2014-3328-1.
JDBC API Tutorial and Reference, Second Edition: Universal Data Access for the Java 2 Platform.
O'Reilly & Associates.

Articles

[1] [Bosak1999] Jon Bosak and Tim Bray. XML and the Second-Generation Web.
Scientific American. 16-25. May 1999.

[2] [Johnson1998] Ralph Johnson. Designing Reusable Classes. Journal of
Object-Oriented Programming. 19-45. June/July 1998.

[3] [Wirfs-Brock1991] Rebecca J. Wirfs-Brock. Object-Oriented Frameworks.
American Programmer. 21-29. October 1991.

Originally written by:
Bill Brooks
California Polytechnic State University

Modifications and conversion to html by:
~jaf30@cornell.edu, Cornell University

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