net.sf.saxon.instruct
Class Param

java.lang.Object
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  +--net.sf.saxon.instruct.Instruction
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        +--net.sf.saxon.instruct.GeneralVariable
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              +--net.sf.saxon.instruct.DefiningVariable
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                    +--net.sf.saxon.instruct.Param
All Implemented Interfaces:
Binding, Instr, Locatable, java.io.Serializable, javax.xml.transform.SourceLocator

public final class Param
extends DefiningVariable

The compiled form of an xsl:param element in the stylesheet or an external variable in a Query.
The xsl:param element in XSLT has mandatory attribute name and optional attribute select. It can also be specified as required="yes" or required="no". In standard XQuery external variables are always required, and no default value can be specified; but Saxon provides an extension pragma that allows a query to specify a default.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class net.sf.saxon.instruct.GeneralVariable
variableFingerprint
 
Fields inherited from class net.sf.saxon.instruct.Instruction
children
 
Constructor Summary
Param()
           
 
Method Summary
 java.lang.String getInstructionName()
          Get the name of this instruction for diagnostic and tracing purposes
 TailCall processLeavingTail(XPathContext context)
          ProcessLeavingTail: called to do the real work of this instruction.
 void setConversion(Expression convertor)
           
 
Methods inherited from class net.sf.saxon.instruct.DefiningVariable
evaluateVariable, getRequiredType, getSlotNumber, getVariableName, setRequiredType, setSlotNumber, setVariableName
 
Methods inherited from class net.sf.saxon.instruct.GeneralVariable
containsLocals, getCardinality, getItemType, getSelectExpression, getSelectValue, getVariableFingerprint, init, isAssignable, isGlobal, isRequiredParam, isTunnelParam, setAssignable, setContainsLocals, setGlobal, setRequiredParam, setSelect, setTunnel, setVariableFingerprint
 
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

Param

public Param()
Method Detail

setConversion

public void setConversion(Expression convertor)

getInstructionName

public java.lang.String getInstructionName()
Get the name of this instruction for diagnostic and tracing purposes

Overrides:
getInstructionName in class GeneralVariable

processLeavingTail

public TailCall processLeavingTail(XPathContext context)
                            throws javax.xml.transform.TransformerException
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 interface Instr
Specified by:
processLeavingTail in class Instruction
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.
javax.xml.transform.TransformerException