XML Input Basics (Reminders)

A few things to keep in mind--first, XML is case-sensitive when it comes to element and attribute names, so ``createCity'' is not the same as ``cReAtEcity''. In general:

• Any attribute whose value is obviously a number (such as x and y in createCity) will typically follow the aforementioned regular expression (0|(-?[1-9][0-9]*)). In other words, integers. A programmatic description is that you should be able to obtain the integer value of numerical attributes by obtaining their values as strings and passing them through Integer.parseInt(). If that method throws an exception when attempting to parse a numerical value, you can assume that attribute's value is invalid.

• Any attribute whose value is defined to be a string (such as name in createCity) must have a non-numeric first character; however, the remaining part can consist of any combination of numbers, upper case and lower case letters, and the underscore character. Thus, the regular expression for string attributes will be ([_a-zA-Z][_a-zA-Z0-9]*).

  But the XML schema and the XmlUtility class provides a method to do type-checking for you so don't worry about this part.