IBM Version 5 manual XML digital, Book Library

</BOOK>

<BOOK ID=”B3.2”> <TITLE>great novel</TITLE> <COPIES>10</COPIES>

</BOOK>

<BOOK ID=”B5.5”> <TITLE>good story</TITLE> <COPIES>10</COPIES>

</BOOK>

</LIBRARY>

The path /child::book/child::copies selects all copies element children of book, which are defined under the document’s root. The above path can also be written as /book/copies.

The XPath location step makes the selection of document part based on the basis and the predicate. The basis performs a selection based on axis name and node test. Then the predicate performs additional selections based on the outcome of the selection from the basis. A simple example of this is as follows:

The path /child::book[position()-1]selects the first book element under root. This location step can also be written as /book[1]

For example, the path /book/author/@* would have selected all the author elements’ attributes

The path /book/author[@type=’old’] would have selected all the author elements with type attribute equal to “old”.

The W3C has published a working draft for a new set of requirements for XPath on February 2001. It has set of number of goals. It has stated that XML must:

￿Simplify manipulation of XML Schema-types content

￿Simplify manipulation of string-content

￿Support related XML standards

￿Improve ease of use

￿Improve interoperability

￿Improve i18n (International Language Support)

￿Maintain backward compatibility

￿Enable improved processor efficiency

2.7XML digital

Any document, XML or otherwise, can be encrypted entirely and be transmitted to one or more recipients. Suppose we would only want to encrypt parts of the

34 The XML Files: Development of XML/XSL Applications Using WebSphere Studio