net.sf.saxon.instruct
Class ProcessingInstruction

java.lang.Object
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  +--net.sf.saxon.instruct.Instruction
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        +--net.sf.saxon.instruct.ExprInstruction
              |
              +--net.sf.saxon.instruct.SimpleNodeConstructor
                    |
                    +--net.sf.saxon.instruct.ProcessingInstruction

All Implemented Interfaces:

Expression, Instr, Locatable, java.io.Serializable, javax.xml.transform.SourceLocator

public class ProcessingInstruction

extends SimpleNodeConstructor

An xsl:processing-instruction element in the stylesheet.

See Also:

Serialized Form

Field Summary

 

Fields inherited from class net.sf.saxon.instruct.SimpleNodeConstructor

select, separator

 

Fields inherited from class net.sf.saxon.instruct.Instruction

children

 

Constructor Summary

ProcessingInstruction(Expression name)           Create an xsl:processing-instruction instruction

 

Method Summary
void	display(int level, NamePool pool)           Display this instruction as an expression, for diagnostics
protected  int	evaluateNameCode(XPathContext context)
int	getCardinality()           Determine the static cardinality of the expression.
int	getDependencies()           Determine which aspects of the context the expression depends on.
java.lang.String	getInstructionName()           Get the name of this instruction for diagnostic and tracing purposes
ItemType	getItemType()           Determine the data type of the expression, if possible.
void	getXPathExpressions(java.util.List list)           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)
TailCall	processLeavingTail(XPathContext context)           Process this instruction, that is, produce a processing-instruction node in the result sequence.
void	promoteInst(PromotionOffer offer)           Offer promotion for subexpressions.
void	typeCheck(StaticContext env)

 

Methods inherited from class net.sf.saxon.instruct.SimpleNodeConstructor

analyze, evaluateItem, expandChildren, setSelect, setSeparator

 

Methods inherited from class net.sf.saxon.instruct.ExprInstruction

effectiveBooleanValue, evaluateAsString, getSpecialProperties, getSubExpressions, iterate, promote, simplify

 

Methods inherited from class net.sf.saxon.instruct.Instruction

assembleParams, assembleTunnelParams, displayChildren, dynamicError, dynamicError, getChildren, getColumnNumber, getExecutable, getInstructionNamespace, getLineNumber, getPublicId, getSourceLocator, getSystemId, process, processChildren, processChildrenLeavingTail, recoverableError, setChildren, setExecutable, setSourceLocation

 

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

 

Constructor Detail

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

getInstructionName

public java.lang.String getInstructionName()

Get the name of this instruction for diagnostic and tracing purposes

Specified by:

getInstructionName in class Instruction

Returns:

the string "xsl:processing-instruction"

getItemType

public ItemType getItemType()

Description copied from interface: Expression

Determine the data type of the expression, if possible. All expression return sequences, in general; this method determines the type of the items within the sequence, assuming that (a) this is known in advance, and (b) it is the same for all items in the sequence.

This method should always return a result, though it may be the best approximation that is available at the time.

Specified by:

getItemType in interface Expression

Overrides:

getItemType in class Instruction

Returns:

a value such as Type.STRING, Type.BOOLEAN, Type.NUMBER, Type.NODE, or Type.ITEM (meaning not known at compile time)

getCardinality

public int getCardinality()

Description copied from interface: 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.

This method should always return a result, though it may be the best approximation that is available at the time.

Specified by:

getCardinality in interface Expression

Overrides:

getCardinality in class Instruction

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).

typeCheck

public void typeCheck(StaticContext env)
               throws XPathException

Specified by:

typeCheck in class SimpleNodeConstructor

XPathException

getDependencies

public int getDependencies()

Description copied from class: ExprInstruction

Determine which aspects of the context the expression depends on. The result is a bitwise-or'ed value composed from constants such as StaticProperty.DEPENDS_ON_CONTEXT_ITEM and StaticProperty.DEPENDS_ON_CURRENT_ITEM. 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.

Specified by:

getDependencies in interface Expression

Overrides:

getDependencies in class ExprInstruction

Returns:

a set of bit-significant flags identifying the dependencies of the expression

getXPathExpressions

public void getXPathExpressions(java.util.List list)

Description copied from class: ExprInstruction

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:

getXPathExpressions in class SimpleNodeConstructor

Parameters:

list - A list to be populated with the list of XPath expressions

promoteInst

public 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 class SimpleNodeConstructor

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

processLeavingTail

public TailCall processLeavingTail(XPathContext context)
                            throws javax.xml.transform.TransformerException

Process this instruction, that is, produce a processing-instruction node in the result sequence.

Specified by:

processLeavingTail in interface Instr

Specified by:

processLeavingTail in class Instruction

Parameters:

context - the dynamic context of this transformation

Returns:

always returns null in this implementation

Throws:

javax.xml.transform.TransformerException - if any non-recoverable dynamic error occurs

evaluateNameCode

protected int evaluateNameCode(XPathContext context)
                        throws XPathException

Overrides:

evaluateNameCode in class SimpleNodeConstructor

XPathException

display

public void display(int level,
                    NamePool pool)

Description copied from class: SimpleNodeConstructor

Display this instruction as an expression, for diagnostics

Specified by:

display in interface Expression

Overrides:

display in class SimpleNodeConstructor

Parameters:

level - indentation level for this expression