CS 445: Real-Time Systems

hw6.memo Jeffrey Levetin (tron@cs.umb.edu) rick butterworth(rickb@cs.umb.edu) Fall 2002 theCourses.xml & theSections.xml theCourses.xml - Design Decisions We decided to first create theCourses.xml with some attributes. We did it, but IE couldn't display it very nicely - perhaps IE can interpret < as < but still thinks that it's all just text. So we went back and redid it using only elements. We believe that may be more consistent anyway. Since some of the parts, e.g. Description, should be text within an element, we thought it would make sense to make everything an element. The output looks like: CS445 CS 445: Real-Time Systems Covers the entire development process of a real-time system, from the requirements specification and design to implementation and testing, including real-time programming, low-level software issues, and hardware architectures. Emphasizes timing constraints and scheduling principles. Subtopics include the four layers of real-time system development: real-time design methodologies, real-time design programming language constructs, real-time kernels, and real-time hardware architectures. CS 241 CS 310 We decided to make a few changes in Courses.xml to make it more consistent and thus easier for a computer to understand. Specifically we changed (fixed) the line 'permission of the instructor' in CS430 to have the appropriate tag. **** there is a problem with CS320 CS410 CS430 CS451 CS460 CS470 CS480 and their prerequisites. Sections.xml - Design Decisions We decided to create theSections.xml without using attributes, see above for a discussion. We decided to keep all the data so the output will look like:

261656 CS110 1 JAVA Intro prog (4.0) M-2-116 M W 19:00-20:30 Cohen, Robert

261656 CS110 1d JAVA Intro prog (4.0) M-2-116 M 17:30-18:45 Staff Unassigned

Because of the way Sections.xml is we had to deal with each part individually. We also had to 'eat' the first element at the which has nothing to do with courses (it is setting up the table headings). Also, we had to allow for the item we wanted to be in several places. For example, many instructors have web sites and thus are within an element. However, a few instructors and, of course, Staff Unassigned have no such thing. Thus we made use of xsl:choose to pick off the one we wanted. Problems Encountered The biggest problem we encountered was that there were serveral lines in the *.xml files which seemed to prevent any output from Xalan. These lines were: and We're not sure what the problem is. Our best guess is that it's some sort of namespace problem. Anyhow, after we removed these our xsl file started to work.