Class CombinedNodeTest

java.lang.Object
net.sf.saxon.pattern.NodeTest
net.sf.saxon.pattern.CombinedNodeTest
All Implemented Interfaces:
Serializable, ItemType
public class CombinedNodeTest extends NodeTest
A CombinedNodeTest combines two nodetests using one of the operators union (=or), intersect (=and), difference (= "and not"). This arises when optimizing a union (etc) of two path expressions using the same axis. A CombinedNodeTest is also used to support constructs such as element(N,T), which can be expressed as (element(N,*) AND element(*,T))
Author:
Michael H. Kay
See Also:

  • Constructor Details

    • CombinedNodeTest

      public CombinedNodeTest(NodeTest nt1, int operator, NodeTest nt2)
      Create a NodeTest that combines two other node tests
      Parameters:
      nt1 - the first operand. Note that if the defaultPriority of the pattern is required, it will be taken from that of the first operand.
      operator - one of Token.UNION, Token.INTERSECT, Token.EXCEPT
      nt2 - the second operand

  • Method Details

    • matches

      public boolean matches(int nodeKind, NodeName name, int annotation)
      Test whether this node test is satisfied by a given node. This method is only fully supported for a subset of NodeTests, because it doesn't provide all the information needed to evaluate all node tests. In particular (a) it can't be used to evaluate a node test of the form element(N,T) or schema-element(E) where it is necessary to know whether the node is nilled, and (b) it can't be used to evaluate a node test of the form document-node(element(X)). This in practice means that it is used (a) to evaluate the simple node tests found in the XPath 1.0 subset used in XML Schema, and (b) to evaluate node tests where the node kind is known to be an attribute.
      Specified by:
      matches in class NodeTest
      Parameters:
      nodeKind - The kind of node to be matched
      name - identifies the expanded name of the node to be matched. The value should be null for a node with no name.
      annotation - The actual content type of the node

    • matches

      public boolean matches(TinyTree tree, int nodeNr)
      Test whether this node test is satisfied by a given node on a TinyTree. The node must be a document, element, text, comment, or processing instruction node. This method is provided so that when navigating a TinyTree a node can be rejected without actually instantiating a NodeInfo object.
      Overrides:
      matches in class NodeTest
      Parameters:
      tree - the TinyTree containing the node
      nodeNr - the number of the node within the TinyTree
      Returns:
      true if the node matches the NodeTest, otherwise false

    • matches

      public boolean matches(NodeInfo node)
      Test whether this node test is satisfied by a given node. This alternative method is used in the case of nodes where calculating the fingerprint is expensive, for example DOM or JDOM nodes.
      Overrides:
      matches in class NodeTest
      Parameters:
      node - the node to be matched

    • toString

      public String toString(NamePool pool)
      Description copied from class: NodeTest
      Display the type descriptor for diagnostics
      Specified by:
      toString in interface ItemType
      Overrides:
      toString in class NodeTest
      Parameters:
      pool - the name pool
      Returns:
      a string representation of the type, in notation resembling but not necessarily identical to XPath syntax

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getSuperType

      public ItemType getSuperType(TypeHierarchy th)
      Get the supertype of this type. This isn't actually a well-defined concept: the types form a lattice rather than a strict hierarchy.
      Specified by:
      getSuperType in interface ItemType
      Overrides:
      getSuperType in class NodeTest
      Parameters:
      th - the type hierarchy cache
      Returns:
      the supertype, or null if this type is item()

    • getNodeKindMask

      public int getNodeKindMask()
      Get a mask indicating which kinds of nodes this NodeTest can match. This is a combination of bits: 1<<Type.ELEMENT for element nodes, 1<<Type.TEXT for text nodes, and so on.
      Overrides:
      getNodeKindMask in class NodeTest
      Returns:
      a combination of bits: 1invalid input: '<'invalid input: '<'Type.ELEMENT for element nodes, 1invalid input: '<'invalid input: '<'Type.TEXT for text nodes, and so on

    • getPrimitiveType

      public int getPrimitiveType()
      Get the basic kind of object that this ItemType matches: for a NodeTest, this is the kind of node, or Type.Node if it matches different kinds of nodes.
      Specified by:
      getPrimitiveType in interface ItemType
      Overrides:
      getPrimitiveType in class NodeTest
      Returns:
      the node kind matched by this node test

    • getRequiredNodeNames

      public IntSet getRequiredNodeNames()
      Get the set of node names allowed by this NodeTest. This is returned as a set of Integer fingerprints. A null value indicates that all names are permitted (i.e. that there are no constraints on the node name). The default implementation returns null.
      Overrides:
      getRequiredNodeNames in class NodeTest
      Returns:
      the set of integer fingerprints of the node names that this node test can match.

    • getContentType

      public SchemaType getContentType()
      Get the content type allowed by this NodeTest (that is, the type annotation of the matched nodes). Return AnyType if there are no restrictions. The default implementation returns AnyType.
      Overrides:
      getContentType in class NodeTest
      Returns:
      the type annotation that all nodes matching this NodeTest must satisfy

    • getAtomizedItemType

      public AtomicType getAtomizedItemType()
      Get the item type of the atomic values that will be produced when an item of this type is atomized (assuming that atomization succeeds)
      Specified by:
      getAtomizedItemType in interface ItemType
      Overrides:
      getAtomizedItemType in class NodeTest
      Returns:
      the best available item type of the atomic values that will be produced when an item of this type is atomized

    • isAtomizable

      public boolean isAtomizable()
      Ask whether values of this type are atomizable
      Specified by:
      isAtomizable in interface ItemType
      Overrides:
      isAtomizable in class NodeTest
      Returns:
      true unless it is known that these items will be elements with element-only content, in which case return false

    • getFingerprint

      public int getFingerprint()
      Get the name of the nodes matched by this nodetest, if it matches a specific name. Return -1 if the node test matches nodes of more than one name
      Overrides:
      getFingerprint in class NodeTest

    • isNillable

      public boolean isNillable()
      Determine whether the content type (if present) is nillable
      Overrides:
      isNillable in class NodeTest
      Returns:
      true if the content test (when present) can match nodes that are nilled

    • hashCode

      public int hashCode()
      Returns a hash code value for the object.
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object other)
      Indicates whether some other object is "equal to" this one.
      Overrides:
      equals in class Object

    • getDefaultPriority

      public double getDefaultPriority()
      Get the default priority of this nodeTest when used as a pattern. In the case of a union, this will always be (arbitrarily) the default priority of the first operand. In other cases, again somewhat arbitrarily, it is 0.25, reflecting the common usage of an intersection to represent the pattern element(E, T).
      Returns:
      the default priority

    • getComponentNodeTests

      public NodeTest[] getComponentNodeTests()
      Get the two parts of the combined node test
      Returns:
      the two operands

    • getOperator

      public int getOperator()
      Get the operator used to combine the two node tests: one of Token.UNION, Token.INTERSECT, Token.EXCEPT,
      Returns:
      the operator

    • visitNamedSchemaComponents

      public void visitNamedSchemaComponents(SchemaComponentVisitor visitor) throws XPathException
      Visit all the schema components used in this ItemType definition
      Specified by:
      visitNamedSchemaComponents in interface ItemType
      Overrides:
      visitNamedSchemaComponents in class NodeTest
      Parameters:
      visitor - the visitor class to be called when each component is visited
      Throws:
      XPathException - if an error occurs