Enterprise J2ME Developing Mobile Java Applications [Electronic resources] نسخه متنی

3.2 Introducing iFeedBack

In order to tap J2ME smart clients' potential in emerging markets and seek new ideas of killer applications, NexTel, Sun Microsystems, and Motorola jointly sponsored the University Wireless Developer Contest in the United States. My contest entry "iFeedBack: A Single Sign-on Mobile Survey Tool for University Students" won the grand prize of $20,000. In the rest of this chapter, I use iFeedBack as an example to illustrate what can be done with managed smart clients. The complete source code of the iFeedBack application can be downloaded from this book's Web site (see "Resources").

3.2.1 The Problems to Solve

A big "business problem" we had for a long time in the higher education enterprise (i.e., universities) was the lack of communication channels between knowledge producers (professors) and consumers (students). College students in large universities usually have little interaction with professors. The lack of feedback on course advances and teaching techniques is one of the major factors that impede effective learning. Course evaluation surveys at the end of the semester often are the only way a student can convey his or her opinions of the teaching to the professor. But there are two problems with such delayed instructor surveys: They are too late for the students to remember earlier incidents, and they are too late for the professor to take corrective measures.

An open, real-time, and convenient communication channel between professors and students will benefit both parties. iFeedBack is a mobile survey application that allows questionnaires to be presented and answered anytime, anywhere. It is not only suitable for frequent instructor surveys, but can also be used in in-class quizzes and homework assignments.

3.2.2 Architecture

The overall architecture of iFeedBack is illustrated in Figure 3.1.

There are three major components in an iFeedBack deployment:

Each class has its own survey site that feeds current questions to mobile clients and receives time-stamped answers over the HTTP. The professor and teaching assistants have administrative access to that site.

The university provides a single sign-on service. This server authenticates students and issues time-limited access tokens to survey sites. The student uses tokens to access class survey sites. Class sites also connect to the authentication server to verify the tokens. To ensure interoperability with potentially large numbers of different clients, this single sign-on service is provided via an XML Web Services interface.

The smart MIDP client provides user interface and temporary storage for time-stamped answers. It also manages authentication credentials and maintains a list of endpoint URLs for classes the student is attending.

3.2.3 Real-World Deployment

iFeedBack is a prototype application that is designed to sell to universities rather than to individual students. The backend services are deployed into the university IT infrastructure: The single sign-on services should be linked with the existing electronic ID systems; the class surveys could be integrated with existing campus-wide course Web sites, such as the blackboard system. The two serverside components I provided with the sample application are for proof-of-concept demonstration only.