Exercises for Lecture 1

Consider a collection of recipes stored in raw text files such as this example. We design an XML version of a recipe collection:

• recipes consist of ingredients, steps for preparation, possibly some comments, and a specification of its nutrition
• an ingredient can be simple or composite
• a simple ingredient has a name, an amount (possibly unspecified), an a unit (unless amount is dimensionless)
• a composite ingredient is recursively a recipe with ingredients and preparation

<?xml version="1.0" encoding="UTF-8"?> <collection> <description> Some recipes used for the XML tutorial. </description> <recipe> <title>Beef Parmesan with Garlic Angel Hair Pasta</title> <ingredient name="beef cube steak" amount="1.5" unit="pound"/> ... <preparation> <step> Preheat oven to 350 degrees F (175 degrees C). </step> ... </preparation> <comment> Make the meat ahead of time, and refrigerate over night, the acid in the tomato sauce will tenderize the meat even more. If you do this, save the mozzarella till the last minute. </comment> <nutrition calories="1167" fat="23" carbohydrates="45" protein="32"/> </recipe> ... </collection>

Note that XML documents (usually) begin with an XML declaration (<?xml ...?>)

1. Add this ravioli recipe to the recipe collection XML file. Make sure the result is wellformed XML.

2. Design an XML language to represent weblogs, that is, diaries aimed for publication on the web. There are countless different solutions, try to keep it simple.

3. Use the W3C validator to check whether www.jp.dk and www.microsoft.com (or some other Web pages) are valid HTML. If not, see what kinds of errors there are.

4. This HTML page heavily uses physical markup (ex. <i>, <tt>, <font>, color="blue", ...).
   • Convert it to use only logical markup (ex. <em>, <h2>, <code>, ...)
   • Add a CSS stylesheet to obtain the original looks.

5. Study the list of selected online XML resources from the slides and the collection of XML applications.

Tips

To check that an XML document file.xml is wellformed XML, you can either

• try viewing the page in Explorer or Mozilla,
• use an XML editor. E.g. the free Morphon editor(Java, any platform), the xin editor or a Home edition of the XMLspy (both for Windows).
• use a piece of Java Xerces example code. In this case you should first download the packages: xercesImpl.jar, xercesSamples.jar and xmlParserAPIs.jar (right-click on the links and choose save-as) and then type (on Linux/Unix)

  java -classpath xercesImpl.jar:xercesSamples.jar:xmlParserAPIs.jar dom.Writer file.xml >out.xml
  
  

  On Windows you type:

  java -classpath xercesImpl.jar;xercesSamples.jar;xmlParserAPIs.jar dom.Writer file.xml >out.xml
  
  

  The program parses the file named file.xml, checks if it is well-formed and outputs the file. (The output is redirected to the file out.xml).

To run the W3C validator on a page without a DOCTYPE and encoding, try using "HTML 4.01 Transitional" and "iso-8859-1".