Package net.sf.saxon.pattern
This package provides classes associated with XSLT pattern handling.
The principal classes are:
Pattern:
This represents an XSLT Pattern. There is a static method Pattern.make() which is
used to construct a Pattern from a String (it is a factory method rather than a
constructor, because it typically returns some subclass of Pattern according
to the syntax supplied). Subclasses of Pattern represent different kinds of pattern
such as LocationPathPattern and IDKeyPattern. What they all have in common is a match()
method, which determines whether a given node matches the pattern. A pattern is
not in itself an Expression, but the class PatternSponsor
is used
to wrap a pattern making it look like an expression for the benefit of the static analysis
(allowing the same mechanisms to be used for example to find all the references to a variable).
NodeTest:
This represents a NodeTest within a step of an XPath expression. A NodeTest performs several
roles: as well as its use in conjuction with an axis to form a step of a path expression,
it acts as an ItemType used in handling type checking of nodes, and (wrapped in a NodeTestPattern)
it acts as an XSLT pattern for use in constructs such as the match
attribute of
xsl:template
and xsl:key
.
A NodeTest is used directly to implement simple patterns such as match="item"
or match="*"
. There are several subclasses of NodeTest, depending on the conditions
to be matched: node type, node name, namespace URI, and so on. The class AnyNodeTest matches any node,
while NoNodeTest matches nothing. NodeTests can also be combined using the operators of intersection,
difference, and union, to describe the more complex types that are sometimes computed by the type
checking machinery.
Michael H. Kay
Saxonica Limited
9 February 2005
-
Interface Summary Interface Description PatternFinder This interface enables a client to find all nodes in a document that match a particular pattern. -
Class Summary Class Description AnyChildNodePattern An AnyChildNodePattern is the pattern node(), which matches any node except a root node, an attribute node, or a namespace node: in other words, any node that is the child of another node.AnyNodeTest NodeTest is an interface that enables a test of whether a node has a particular name and type.CombinedNodeTest A CombinedNodeTest combines two nodetests using one of the operators union (=or), intersect (=and), difference (= "and not").ContentTypeTest NodeTest is an interface that enables a test of whether a node matches particular conditions.DocumentNodeTest A DocumentNodeTest implements the test document-node(element(~,~))EmptySequenceTest NodeTest is an interface that enables a test of whether a node has a particular name and type.IDPattern An IDPattern is a pattern of the form id("literal") or id($variable)IdrefTest IdrefTest is a test that cannot be represented directly in XPath or XSLT patterns, but which is used internally for matching IDREF nodes: it tests whether the node has the is-idref propertyKeyPattern A KeyPattern is a pattern of the form key(keyname, keyvalue)LocalNameTest NodeTest is an interface that enables a test of whether a node has a particular name and type.LocationPathPattern A LocationPathPattern represents a path, for example of the form A/B/C...NamespaceTest NodeTest is an interface that enables a test of whether a node has a particular name and type.NameTest NodeTest is an interface that enables a test of whether a node has a particular name and type.NodeKindTest NodeTest is an interface that enables a test of whether a node has a particular name and kind.NodeTest A NodeTest is a simple kind of pattern that enables a context-free test of whether a node has a particular name.NodeTestPattern A NodeTestPattern is a pattern that consists simply of a NodeTest.Pattern A Pattern represents the result of parsing an XSLT pattern string.PatternSponsor The PatternSponsor class allows a Pattern to be treated like an expression.SubstitutionGroupTest NodeTest is an interface that enables a test of whether a node has a particular name and type.UnionPattern A pattern formed as the union (or) of two other patterns