Package net.sf.saxon.instruct
Class ProcessingInstruction
- java.lang.Object
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- net.sf.saxon.expr.Expression
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- net.sf.saxon.instruct.Instruction
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- net.sf.saxon.instruct.SimpleNodeConstructor
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- net.sf.saxon.instruct.ProcessingInstruction
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- All Implemented Interfaces:
java.io.Serializable
,javax.xml.transform.SourceLocator
,LocationProvider
,SaxonLocator
,EvaluableItem
,SequenceIterable
,TailCallReturner
,InstructionInfo
,org.xml.sax.Locator
public class ProcessingInstruction extends SimpleNodeConstructor
An xsl:processing-instruction element in the stylesheet, or a processing-instruction constructor in a query- See Also:
- Serialized Form
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Field Summary
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Fields inherited from class net.sf.saxon.instruct.SimpleNodeConstructor
select
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Fields inherited from class net.sf.saxon.expr.Expression
EVALUATE_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, staticProperties
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Constructor Summary
Constructors Constructor Description ProcessingInstruction(Expression name)
Create an xsl:processing-instruction instruction
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description protected java.lang.String
checkContent(java.lang.String data, XPathContext context)
Check the content of the node, and adjust it if necessaryExpression
copy()
Copy an expression.int
evaluateNameCode(XPathContext context)
Run-time method to compute the name of the node being constructed.void
explain(ExpressionPresenter out)
Diagnostic print of expression structure.int
getCardinality()
Determine the static cardinality of the expression.int
getDependencies()
Determine which aspects of the context the expression depends on.int
getInstructionNameCode()
Get the name of this instruction for diagnostic and tracing purposesItemType
getItemType(TypeHierarchy th)
Get the item type of the items returned by evaluating this instructionExpression
getNameExpression()
Get the expression that defines the processing instruction namejava.util.Iterator
iterateSubExpressions()
Get the immediate sub-expressions of this expression.void
localTypeCheck(ExpressionVisitor visitor, ItemType contextItemType)
Method to perform type-checking specific to the kind of instructionTailCall
processLeavingTail(XPathContext context)
Process this instruction, that is, produce a processing-instruction node in the result sequence.protected void
promoteInst(PromotionOffer offer)
Offer promotion for subexpressions.boolean
replaceSubExpression(Expression original, Expression replacement)
Replace one subexpression by a replacement subexpressionExpression
simplify(ExpressionVisitor visitor)
Simplify an expression.-
Methods inherited from class net.sf.saxon.instruct.SimpleNodeConstructor
computeCardinality, computeSpecialProperties, createsNewNodes, evaluateItem, expandChildren, getSelect, iterate, optimize, setSelect, typeCheck
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Methods inherited from class net.sf.saxon.instruct.Instruction
assembleParams, assembleTunnelParams, dynamicError, evaluateAsString, getConstructType, getImplementationMethod, getSourceLocator, isXSLT, process, promote
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Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, dynamicError, effectiveBooleanValue, evaluatePendingUpdates, explain, findParentOf, getColumnNumber, getColumnNumber, getContainer, getExecutable, getHostLanguage, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, isUpdatingExpression, iterateEvents, markTailFunctionCalls, resetLocalStaticProperties, setContainer, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toString, typeError
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Constructor Detail
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ProcessingInstruction
public ProcessingInstruction(Expression name)
Create an xsl:processing-instruction instruction- Parameters:
name
- the expression used to compute the name of the generated processing-instruction
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Method Detail
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getInstructionNameCode
public int getInstructionNameCode()
Get the name of this instruction for diagnostic and tracing purposes- Overrides:
getInstructionNameCode
in classInstruction
- Returns:
- the string "xsl:processing-instruction"
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getNameExpression
public Expression getNameExpression()
Get the expression that defines the processing instruction name- Returns:
- the expression that defines the processing instruction name
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getItemType
public ItemType getItemType(TypeHierarchy th)
Description copied from class:Instruction
Get the item type of the items returned by evaluating this instruction- Overrides:
getItemType
in classInstruction
- Parameters:
th
- the type hierarchy cache- Returns:
- the static item type of the instruction
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getCardinality
public int getCardinality()
Description copied from class:Expression
Determine the static cardinality of the expression. This establishes how many items there will be in the result of the expression, at compile time (i.e., without actually evaluating the result.- Overrides:
getCardinality
in classExpression
- Returns:
- one of the values Cardinality.ONE_OR_MORE, Cardinality.ZERO_OR_MORE, Cardinality.EXACTLY_ONE, Cardinality.ZERO_OR_ONE, Cardinality.EMPTY. This default implementation returns ZERO_OR_MORE (which effectively gives no information).
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simplify
public Expression simplify(ExpressionVisitor visitor) throws XPathException
Description copied from class:Instruction
Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression). The default implementation does nothing.- Overrides:
simplify
in classSimpleNodeConstructor
- Parameters:
visitor
- an expression visitor- Returns:
- the simplified expression
- Throws:
XPathException
- if an error is discovered during expression rewriting
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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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localTypeCheck
public void localTypeCheck(ExpressionVisitor visitor, ItemType contextItemType) throws XPathException
Description copied from class:SimpleNodeConstructor
Method to perform type-checking specific to the kind of instruction- Specified by:
localTypeCheck
in classSimpleNodeConstructor
- Parameters:
visitor
- an expression visitorcontextItemType
- the static type of the context item- Throws:
XPathException
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getDependencies
public int getDependencies()
Description copied from class:Expression
Determine which aspects of the context the expression depends on. The result is a bitwise-or'ed value composed from constants such as XPathContext.VARIABLES and XPathContext.CURRENT_NODE. The default implementation combines the intrinsic dependencies of this expression with the dependencies of the subexpressions, computed recursively. This is overridden for expressions such as FilterExpression where a subexpression's dependencies are not necessarily inherited by the parent expression.- Overrides:
getDependencies
in classExpression
- Returns:
- a set of bit-significant flags identifying the dependencies of the expression
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iterateSubExpressions
public java.util.Iterator iterateSubExpressions()
Description copied from class:Expression
Get the immediate sub-expressions of this expression. Default implementation returns a zero-length array, appropriate for an expression that has no sub-expressions.- Overrides:
iterateSubExpressions
in classSimpleNodeConstructor
- Returns:
- an iterator containing the sub-expressions of this expression
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replaceSubExpression
public boolean replaceSubExpression(Expression original, Expression replacement)
Replace one subexpression by a replacement subexpression- Overrides:
replaceSubExpression
in classSimpleNodeConstructor
- Parameters:
original
- the original subexpressionreplacement
- the replacement subexpression- Returns:
- true if the original subexpression is found
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promoteInst
protected void promoteInst(PromotionOffer offer) throws XPathException
Offer promotion for subexpressions. 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.- Overrides:
promoteInst
in classSimpleNodeConstructor
- 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 expression- Throws:
XPathException
- if any error is detected
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processLeavingTail
public TailCall processLeavingTail(XPathContext context) throws XPathException
Process this instruction, that is, produce a processing-instruction node in the result sequence.- Specified by:
processLeavingTail
in interfaceTailCallReturner
- Specified by:
processLeavingTail
in classInstruction
- Parameters:
context
- the dynamic context of this transformation- Returns:
- always returns null in this implementation
- Throws:
XPathException
- if any non-recoverable dynamic error occurs
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checkContent
protected java.lang.String checkContent(java.lang.String data, XPathContext context) throws XPathException
Check the content of the node, and adjust it if necessary- Overrides:
checkContent
in classSimpleNodeConstructor
- Parameters:
data
- the supplied contentcontext
- the dynamic context- Returns:
- the original content, unless adjustments are needed
- Throws:
XPathException
- if the content is invalid
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evaluateNameCode
public int evaluateNameCode(XPathContext context) throws XPathException
Description copied from class:SimpleNodeConstructor
Run-time method to compute the name of the node being constructed. This is overridden for nodes that have a name. The default implementation returns -1, which is suitable for unnamed nodes such as comments- Overrides:
evaluateNameCode
in classSimpleNodeConstructor
- Parameters:
context
- the XPath dynamic evaluation context- Returns:
- the name pool nameCode identifying the name of the constructed node
- Throws:
XPathException
- if any failure occurs
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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
- the expression presenter used to display the structure
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