XPath notation

XPath notation used in this specification

XPath is a way to refer to parts of an XML document, for example, a JDF ticket. A simple subset of the XPath language [XPath] is used in the description of an element, attribute or value to identify other elements, attributes and/or values.

The simple subset of XPath used is:

• Element subelement hierarchy is indicated by a slash.

  For example: element/element

• Element attribute hierarchy is indicated by a slash and an at (@) symbol.

  For example: element/@attribute

• Paths beginning with a single slash: '/' indicate root elements.

  For example: /JDF indicates the root JDF node

• Paths beginning with a double slash '//' indicate elements with a parent.

  For example: //ResourcePool indicates a ResourcePool element in an element

• Predicates are always embedded in square brackets. Predicates are used to find a specific node or a node that contains a specific value.

  This document can contain the following types of predicates:

  • E[@A = V]

    The XPath specifies an element E whose attribute A has the value V.

  • E[contains(@A = V)]

    The XPath specifies an element E whose attribute A has some value that contains V.

  • E[@A]

    The XPath specifies an element E in which attribute A is present.

Example 1

XPath: /JDF/ResourcePool/Media/GeneralID[@IDUsage="oce:Orientation"]/@IDValue

This XPath refers to the following part of an XML document:

<JDF>

<ResourcePool>

<Media>

<GeneralID IDUsage="oce:Orientation" IDValue="LongEdgeFeed"/>

</Media>

</ResourcePool>

</JDF>

Example 2

XPath: /JDF[contains(@Types="Trimming")]/ResourcePool/TrimmingParams/GeneralID[@IDUsage="oce:CutWidth"]/@IDValue

This XPath refers to the following part of an XML document:

<JDF Types="Trimming">

<ResourcePool>

<TrimmingParams>

<GeneralID IDUsage="oce:CutWidth" IDValue="<double>"/>

</TrimmingParams>

</ResourcePool>

</JDF>

Example 3

/JDF/ResourcePool/Contact[contains(@ContactTypes="Owner") and @ID="<text>"]/@oce:UserID/oce:ComChannel[@ChannelType="ComputerName"]/@Locator

This XPath refers to the following part of an XML document:

<JDF>

<ResourcePool>

<Contact ID="<text>" ContactTypes="Owner" oce:UserID="<text>">

<oce:ComChannel ChannelType="ComputerName" Locator="<hostname>"/>

</Contact>

</ResourcePool>

</JDF>