Package net.sf.saxon.pattern
Class ConditionalPattern
java.lang.Object
net.sf.saxon.pattern.Pattern
net.sf.saxon.pattern.ConditionalPattern
- All Implemented Interfaces:
Serializable
,SourceLocator
,Container
,PatternFinder
A ConditionalPattern tests a node against one of a number of patterns depending on the value of a condition.
This is used only as a streaming selection.
- See Also:
-
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionint
allocateSlots
(StaticContext env, SlotManager slotManager, int nextFree) Allocate slots to any variables used within the patternanalyze
(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) Type-check the pattern.boolean
Determine whether this pattern is the same as another patternint
Get the dependencies of the pattern.Get a NodeTest that all the nodes matching this pattern must satisfyint
Determine the types of nodes to which this pattern applies.int
hashCode()
Hashcode supporting equals()Iterate over the subexpressions within this patternboolean
matches
(Item item, XPathContext context) Determine if the supplied node matches the patternboolean
matchesBeneathAnchor
(NodeInfo node, NodeInfo anchor, XPathContext context) Determine whether this pattern matches a given Node within the subtree rooted at a given anchor node.void
promote
(PromotionOffer offer, Expression parent) Offer promotion for subexpressions within this pattern.boolean
replaceSubExpression
(Expression original, Expression replacement) Replace a subexpression by a replacement subexpressionvoid
setExecutable
(Executable executable) Set the executable containing this patternvoid
setLineNumber
(int lineNumber) Override method to set the line numbervoid
setOriginalText
(String pattern) Set the original textvoid
setSystemId
(String systemId) Override method to set the system IDsimplify
(ExpressionVisitor visitor) Simplify the pattern: perform any context-independent optimisationsMethods inherited from class net.sf.saxon.pattern.Pattern
getColumnNumber, getContainerGranularity, getDefaultPriority, getExecutable, getFingerprint, getHostLanguage, getLineNumber, getLocationProvider, getPublicId, getSystemId, internalMatches, make, resolveCurrent, selectNodes, setVariableBindingExpression, toString
-
Constructor Details
-
ConditionalPattern
-
-
Method Details
-
setExecutable
Set the executable containing this pattern- Overrides:
setExecutable
in classPattern
- Parameters:
executable
- the executable
-
simplify
Simplify the pattern: perform any context-independent optimisations- Overrides:
simplify
in classPattern
- Parameters:
visitor
- an expression visitor- Returns:
- the optimised Pattern
- Throws:
XPathException
- if a static error is discovered
-
analyze
public Pattern analyze(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException Type-check the pattern. This is only needed for patterns that contain variable references or function calls.- Overrides:
analyze
in classPattern
- Parameters:
visitor
- the expression visitorcontextItemType
- the type of the context item at the point where the pattern is defined. Set to null if it is known that the context item is undefined.- Returns:
- the optimised Pattern
- Throws:
XPathException
- if a static error is discovered
-
promote
Offer promotion for subexpressions within this pattern. The offer will be accepted if the subexpression is not dependent on the factors (e.g. the context item) identified in the PromotionOffer. By default the offer is not accepted - this is appropriate in the case of simple expressions such as constant values and variable references where promotion would give no performance advantage. This method is always called at compile time.Unlike the corresponding method on
Expression
, this method does not return anything: it can make internal changes to the pattern, but cannot return a different pattern. Only certain kinds of promotion are applicable within a pattern: specifically, promotions affecting local variable references within the pattern.- Overrides:
promote
in classPattern
- Parameters:
offer
- details of the offer, for example the offer to move expressions that don't depend on the context to an outer level in the containing expressionparent
-- Throws:
XPathException
- if any error is detected
-
replaceSubExpression
Replace a subexpression by a replacement subexpression- Overrides:
replaceSubExpression
in classPattern
- Parameters:
original
- the expression to be replacedreplacement
- the new expression to be inserted in its place- Returns:
- true if the replacement was carried out
-
setOriginalText
Set the original text- Overrides:
setOriginalText
in classPattern
- Parameters:
pattern
- the original text of the pattern
-
allocateSlots
Allocate slots to any variables used within the pattern- Overrides:
allocateSlots
in classPattern
- Parameters:
env
- the static context in the XSLT stylesheetslotManager
-nextFree
- the next slot that is free to be allocated @return the next slot that is free to be allocated- Returns:
- the next slot that is free to be allocated
-
matches
Determine if the supplied node matches the pattern- Specified by:
matches
in classPattern
- Parameters:
item
- the node to be comparedcontext
- The dynamic context. Only relevant if the pattern uses variables, or contains calls on functions such as document() or key().- Returns:
- true if the node matches either of the operand patterns
- Throws:
XPathException
- if a dynamic error occurs during pattern matching
-
matchesBeneathAnchor
public boolean matchesBeneathAnchor(NodeInfo node, NodeInfo anchor, XPathContext context) throws XPathException Determine whether this pattern matches a given Node within the subtree rooted at a given anchor node. This method is used when the pattern is used for streaming.- Overrides:
matchesBeneathAnchor
in classPattern
- Parameters:
node
- The NodeInfo representing the Element or other node to be tested against the Patternanchor
- The anchor node, which must match any AnchorPattern subpatterncontext
- The dynamic context. Only relevant if the pattern uses variables, or contains calls on functions such as document() or key().- Returns:
- true if the node matches the Pattern, false otherwise
- Throws:
XPathException
- if a dynamic error occurs during pattern matching
-
getNodeKind
public int getNodeKind()Determine the types of nodes to which this pattern applies. Used for optimisation. For patterns that match nodes of several types, return Type.NODE- Overrides:
getNodeKind
in classPattern
- Returns:
- the type of node matched by this pattern. e.g. Type.ELEMENT or Type.TEXT
-
getItemType
Get a NodeTest that all the nodes matching this pattern must satisfy- Specified by:
getItemType
in classPattern
- Returns:
- an ItemType, as specific as possible, which all the matching items satisfy
-
getDependencies
public int getDependencies()Get the dependencies of the pattern. The only possible dependency for a pattern is on local variables. This is analyzed in those patterns where local variables may appear.- Overrides:
getDependencies
in classPattern
- Returns:
- the dependencies, as a bit-significant mask
-
iterateSubExpressions
Iterate over the subexpressions within this pattern- Overrides:
iterateSubExpressions
in classPattern
- Returns:
- an iterator over the subexpressions.
-
setSystemId
Override method to set the system ID- Overrides:
setSystemId
in classPattern
- Parameters:
systemId
- the URI of the module containing the pattern
-
setLineNumber
public void setLineNumber(int lineNumber) Override method to set the line number- Overrides:
setLineNumber
in classPattern
- Parameters:
lineNumber
- the line number of the pattern in the source module
-
equals
Determine whether this pattern is the same as another pattern -
hashCode
public int hashCode()Hashcode supporting equals()
-