Class ApplyTemplates
- java.lang.Object
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- net.sf.saxon.expr.Expression
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- net.sf.saxon.expr.instruct.Instruction
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- net.sf.saxon.expr.instruct.ApplyTemplates
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- All Implemented Interfaces:
java.io.Serializable
,javax.xml.transform.SourceLocator
,LocationProvider
,SaxonLocator
,ITemplateCall
,TailCallReturner
,InstructionInfo
,org.xml.sax.Locator
public class ApplyTemplates extends Instruction implements ITemplateCall
An instruction representing an xsl:apply-templates element in the stylesheet- See Also:
- Serialized Form
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Field Summary
Fields Modifier and Type Field Description protected WithParam[]
actualParams
protected boolean
implicitSelect
protected Mode
mode
protected Expression
select
protected WithParam[]
tunnelParams
protected boolean
useCurrentMode
protected boolean
useTailRecursion
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Fields inherited from class net.sf.saxon.expr.Expression
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, WATCH_METHOD
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Constructor Summary
Constructors Modifier Constructor Description protected
ApplyTemplates()
ApplyTemplates(Expression select, boolean useCurrentMode, boolean useTailRecursion, boolean implicitSelect, Mode mode)
Construct an apply-templates instructino
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description PathMap.PathMapNodeSet
addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
Add a representation of this expression to a PathMap.protected TailCall
apply(XPathContext context, boolean returnTailCall)
Expression
copy()
Copy an expression.boolean
createsNewNodes()
Determine whether this instruction creates new nodes.void
explain(ExpressionPresenter out)
Diagnostic print of expression structure.protected void
explainStreaming(ExpressionPresenter out)
WithParam[]
getActualParams()
Get the actual parameters passed to the called templateint
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().int
getInstructionNameCode()
Get the name of this instruction for diagnostic and tracing purposesint
getIntrinsicDependencies()
Determine the intrinsic dependencies of an expression, that is, those which are not derived from the dependencies of its subexpressions.Mode
getMode()
Get the ModeExpression
getSelectExpression()
Get the select expressionWithParam[]
getTunnelParams()
Get the tunnel parameters passed to the called templateboolean
hasLoopingSubexpression(Expression child)
Given an expression that is an immediate child of this expression, test whether the evaluation of the parent expression causes the child expression to be evaluated repeatedlyprotected void
init(Expression select, boolean useCurrentMode, boolean useTailRecursion, Mode mode)
boolean
isImplicitSelect()
Ask if the select expression was implicitjava.util.Iterator<Expression>
iterateSubExpressions()
Get all the XPath expressions associated with this instruction (in XSLT terms, the expression present on attributes of the instruction, as distinct from the child instructions in a sequence construction)Expression
optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType)
Perform optimisation of an expression and its subexpressions.void
process(XPathContext context)
Process the instruction, without returning any tail callsTailCall
processLeavingTail(XPathContext context)
ProcessLeavingTail: called to do the real work of this instruction.protected void
promoteInst(PromotionOffer offer)
Handle promotion offers, that is, non-local tree rewrites.boolean
replaceSubExpression(Expression original, Expression replacement)
Replace one subexpression by a replacement subexpressionvoid
setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)
Set the actual parameters on the callExpression
simplify(ExpressionVisitor visitor)
Simplify an expression.Expression
typeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType)
Perform type checking of an expression and its subexpressions.boolean
usesCurrentMode()
Ask if mode="#current" was specifiedboolean
useTailRecursion()
Ask if tail recursion is to be used-
Methods inherited from class net.sf.saxon.expr.instruct.Instruction
assembleParams, assembleTunnelParams, computeCardinality, computeSpecialProperties, dynamicError, evaluateAsString, evaluateItem, getConstructType, getExpressionName, getInstructionName, getItemType, getIteratorFromProcessMethod, getSourceLocator, isXSLT, iterate, promote
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Methods inherited from class net.sf.saxon.expr.Expression
adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toString, typeError
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Field Detail
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select
protected Expression select
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actualParams
protected WithParam[] actualParams
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tunnelParams
protected WithParam[] tunnelParams
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useCurrentMode
protected boolean useCurrentMode
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useTailRecursion
protected boolean useTailRecursion
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mode
protected Mode mode
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implicitSelect
protected boolean implicitSelect
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Constructor Detail
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ApplyTemplates
protected ApplyTemplates()
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ApplyTemplates
public ApplyTemplates(Expression select, boolean useCurrentMode, boolean useTailRecursion, boolean implicitSelect, Mode mode)
Construct an apply-templates instructino- Parameters:
select
- the select expressionuseCurrentMode
- true if mode="#current" was specifieduseTailRecursion
- true if this instruction is the last in its templateimplicitSelect
- true if the select expression is implicit, that is, if there was no explicit select expression in the call. This information is used only to make error messages more meaningful.mode
- the mode specified on apply-templates
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Method Detail
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init
protected void init(Expression select, boolean useCurrentMode, boolean useTailRecursion, Mode mode)
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setActualParameters
public void setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)
Set the actual parameters on the call- Parameters:
actualParams
- represents the contained xsl:with-param elements having tunnel="no" (the default)tunnelParams
- represents the contained xsl:with-param elements having tunnel="yes"
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getInstructionNameCode
public int getInstructionNameCode()
Get the name of this instruction for diagnostic and tracing purposes- Overrides:
getInstructionNameCode
in classInstruction
- Returns:
- a code identifying the instruction: typically but not always the fingerprint of a name in the XSLT namespace
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getImplementationMethod
public int getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process(). This method indicates which of these methods is prefered. For instructions this is the process() method.- Overrides:
getImplementationMethod
in classInstruction
- Returns:
- the implementation method, for example
Expression.ITERATE_METHOD
orExpression.EVALUATE_METHOD
orExpression.PROCESS_METHOD
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simplify
public Expression simplify(ExpressionVisitor visitor) throws XPathException
Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression).- Specified by:
simplify
in classInstruction
- Parameters:
visitor
- the expression visitor- Returns:
- the simplified expression
- Throws:
XPathException
- if an error is discovered during expression rewriting
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typeCheck
public Expression typeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException
Description copied from class:Expression
Perform type checking of an expression and its subexpressions. This is the second phase of static optimization.This checks statically that the operands of the expression have the correct type; if necessary it generates code to do run-time type checking or type conversion. A static type error is reported only if execution cannot possibly succeed, that is, if a run-time type error is inevitable. The call may return a modified form of the expression.
This method is called after all references to functions and variables have been resolved to the declaration of the function or variable. However, the types of such functions and variables may not be accurately known if they have not been explicitly declared.
If the implementation returns a value other than "this", then it is required to ensure that the location information in the returned expression have been set up correctly. It should not rely on the caller to do this, although for historical reasons many callers do so.
- Overrides:
typeCheck
in classExpression
- Parameters:
visitor
- an expression visitorcontextItemType
- the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set toType.ITEM_TYPE
- Returns:
- the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
- Throws:
XPathException
- if an error is discovered during this phase (typically a type error)
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optimize
public Expression optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException
Description copied from class:Expression
Perform optimisation of an expression and its subexpressions. This is the third and final phase of static optimization.This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.
- Overrides:
optimize
in classExpression
- Parameters:
visitor
- an expression visitorcontextItemType
- the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set toType.ITEM_TYPE
- Returns:
- the original expression, rewritten if appropriate to optimize execution
- Throws:
XPathException
- if an error is discovered during this phase (typically a type error)
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getIntrinsicDependencies
public int getIntrinsicDependencies()
Description copied from class:Expression
Determine the intrinsic dependencies of an expression, that is, those which are not derived from the dependencies of its subexpressions. For example, position() has an intrinsic dependency on the context position, while (position()+1) does not. The default implementation of the method returns 0, indicating "no dependencies".- Overrides:
getIntrinsicDependencies
in classExpression
- Returns:
- a set of bit-significant flags identifying the "intrinsic" dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty
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copy
public Expression copy()
Copy an expression. This makes a deep copy.- Specified by:
copy
in classExpression
- Returns:
- the copy of the original expression
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createsNewNodes
public final boolean createsNewNodes()
Determine whether this instruction creates new nodes. This implementation returns true (which is almost invariably the case, so it's not worth doing any further analysis to find out more precisely).- Overrides:
createsNewNodes
in classInstruction
- Returns:
- true if the instruction creates new nodes (or if it can't be proved that it doesn't)
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process
public void process(XPathContext context) throws XPathException
Description copied from class:Instruction
Process the instruction, without returning any tail calls- Overrides:
process
in classInstruction
- Parameters:
context
- The dynamic context, giving access to the current node, the current variables, etc.- Throws:
XPathException
- if a dynamic error occurs
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processLeavingTail
public TailCall processLeavingTail(XPathContext context) throws XPathException
Description copied from class:Instruction
ProcessLeavingTail: called to do the real work of this instruction. This method must be implemented in each subclass. The results of the instruction are written to the current Receiver, which can be obtained via the Controller.- Specified by:
processLeavingTail
in interfaceTailCallReturner
- Specified by:
processLeavingTail
in classInstruction
- Parameters:
context
- The dynamic context of the transformation, giving access to the current node, the current variables, etc.- Returns:
- null if the instruction has completed execution; or a TailCall indicating a function call or template call that is delegated to the caller, to be made after the stack has been unwound so as to save stack space.
- Throws:
XPathException
- if a dynamic error occurs during the evaluation of the instruction
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apply
protected TailCall apply(XPathContext context, boolean returnTailCall) throws XPathException
- Throws:
XPathException
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iterateSubExpressions
public java.util.Iterator<Expression> iterateSubExpressions()
Get all the XPath expressions associated with this instruction (in XSLT terms, the expression present on attributes of the instruction, as distinct from the child instructions in a sequence construction)- Overrides:
iterateSubExpressions
in classExpression
- Returns:
- an iterator containing the sub-expressions of this expression
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hasLoopingSubexpression
public boolean hasLoopingSubexpression(Expression child)
Given an expression that is an immediate child of this expression, test whether the evaluation of the parent expression causes the child expression to be evaluated repeatedly- Overrides:
hasLoopingSubexpression
in classExpression
- Parameters:
child
- the immediate subexpression- Returns:
- true if the child expression is evaluated repeatedly
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replaceSubExpression
public boolean replaceSubExpression(Expression original, Expression replacement)
Replace one subexpression by a replacement subexpression- Overrides:
replaceSubExpression
in classExpression
- Parameters:
original
- the original subexpressionreplacement
- the replacement subexpression- Returns:
- true if the original subexpression is found
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getSelectExpression
public Expression getSelectExpression()
Get the select expression- Returns:
- the select expression
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isImplicitSelect
public boolean isImplicitSelect()
Ask if the select expression was implicit- Returns:
- true if no select attribute was explicitly specified
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useTailRecursion
public boolean useTailRecursion()
Ask if tail recursion is to be used- Returns:
- true if tail recursion is used
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usesCurrentMode
public boolean usesCurrentMode()
Ask if mode="#current" was specified- Returns:
- true if mode="#current" was specified
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getMode
public Mode getMode()
Get the Mode- Returns:
- the mode, or null if mode="#current" was specified
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getActualParams
public WithParam[] getActualParams()
Get the actual parameters passed to the called template- Specified by:
getActualParams
in interfaceITemplateCall
- Returns:
- the non-tunnel parameters
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getTunnelParams
public WithParam[] getTunnelParams()
Get the tunnel parameters passed to the called template- Specified by:
getTunnelParams
in interfaceITemplateCall
- Returns:
- the tunnel parameters
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promoteInst
protected void promoteInst(PromotionOffer offer) throws XPathException
Handle promotion offers, that is, non-local tree rewrites.- Overrides:
promoteInst
in classInstruction
- Parameters:
offer
- The type of rewrite being offered- Throws:
XPathException
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addToPathMap
public PathMap.PathMapNodeSet addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
Add a representation of this expression to a PathMap. The PathMap captures a map of the nodes visited by an expression in a source tree.The default implementation of this method assumes that an expression does no navigation other than the navigation done by evaluating its subexpressions, and that the subexpressions are evaluated in the same context as the containing expression. The method must be overridden for any expression where these assumptions do not hold. For example, implementations exist for AxisExpression, ParentExpression, and RootExpression (because they perform navigation), and for the doc(), document(), and collection() functions because they create a new navigation root. Implementations also exist for PathExpression and FilterExpression because they have subexpressions that are evaluated in a different context from the calling expression.
- Overrides:
addToPathMap
in classExpression
- Parameters:
pathMap
- the PathMap to which the expression should be addedpathMapNodeSet
- the PathMapNodeSet to which the paths embodied in this expression should be added- Returns:
- the pathMapNodeSet representing the points in the source document that are both reachable by this expression, and that represent possible results of this expression. For an expression that does navigation, it represents the end of the arc in the path map that describes the navigation route. For other expressions, it is the same as the input pathMapNode.
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explain
public void explain(ExpressionPresenter out)
Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.- Specified by:
explain
in classExpression
- Parameters:
out
- output destination
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explainStreaming
protected void explainStreaming(ExpressionPresenter out)
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