net.sf.saxon.instruct
Class CallTemplate

java.lang.Object
  |
  +--net.sf.saxon.expr.ComputedExpression
        |
        +--net.sf.saxon.instruct.Instruction
              |
              +--net.sf.saxon.instruct.CallTemplate
All Implemented Interfaces:
Container, Expression, InstructionInfoProvider, java.io.Serializable, javax.xml.transform.SourceLocator

public class CallTemplate
extends Instruction

Instruction representing an xsl:call-template element in the stylesheet.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class net.sf.saxon.expr.ComputedExpression
locationId, staticProperties
 
Fields inherited from interface net.sf.saxon.expr.Expression
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD
 
Constructor Summary
CallTemplate(Template template, WithParam[] actualParams, WithParam[] tunnelParams, boolean useTailRecursion, Expression calledTemplateExpression, NamespaceResolver nsContext)
          Construct a CallTemplate instruction.
 
Method Summary
 Expression analyze(StaticContext env, ItemType contextItemType)
          Perform static analysis of an expression and its subexpressions.
 void display(int level, NamePool pool, java.io.PrintStream out)
          Diagnostic print of expression structure.
 InstructionInfo getInstructionInfo()
          Set additional trace properties appropriate to the kind of instruction.
 int getInstructionNameCode()
          Return the name of this instruction.
 Template getTargetTemplate(XPathContext context)
          Get the template, in the case where it is specified dynamically.
 java.util.Iterator 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)
 void process(XPathContext context)
          Process this instruction, without leaving any tail calls.
 TailCall processLeavingTail(XPathContext context)
          Process this instruction.
protected  void promoteInst(PromotionOffer offer)
          Handle promotion offers, that is, non-local tree rewrites.
 Expression simplify(StaticContext env)
          Simplify an expression.
 
Methods inherited from class net.sf.saxon.instruct.Instruction
appendItem, assembleParams, assembleTunnelParams, computeCardinality, computeSpecialProperties, dynamicError, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, getImplementationMethod, getItemType, getSourceLocator, iterate, promote
 
Methods inherited from class net.sf.saxon.expr.ComputedExpression
adoptChildExpression, computeDependencies, computeStaticProperties, dynamicError, dynamicError, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getIntrinsicDependencies, getLineNumber, getLocationId, getParentExpression, getPublicId, getSpecialProperties, getSystemId, markTailFunctionCalls, resetStaticProperties, setLocationId, setParentExpression, typeError
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface javax.xml.transform.SourceLocator
getColumnNumber, getLineNumber, getPublicId, getSystemId
 

Constructor Detail

CallTemplate

public CallTemplate(Template template,
                    WithParam[] actualParams,
                    WithParam[] tunnelParams,
                    boolean useTailRecursion,
                    Expression calledTemplateExpression,
                    NamespaceResolver nsContext)
Construct a CallTemplate instruction.

Parameters:
template - the Template object identifying the template to be called, in the normal case where this is known statically
actualParams - array of WithParam instructions to calculate the actual parameters to be supplied to the call
calledTemplateExpression - expression to calculate the name of the template to be called at run-time, this supports the saxon:allow-avt option
nsContext - the static namespace context of the instruction, needed only in the case where the name of the called template is to be calculated dynamically
Method Detail

getInstructionNameCode

public int getInstructionNameCode()
Return the name of this instruction.

Overrides:
getInstructionNameCode in class Instruction

getInstructionInfo

public InstructionInfo getInstructionInfo()
Set additional trace properties appropriate to the kind of instruction. This implementation adds the template property, which identities the template to be called

Specified by:
getInstructionInfo in interface InstructionInfoProvider
Overrides:
getInstructionInfo in class Instruction

simplify

public Expression simplify(StaticContext env)
                    throws XPathException
Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression).

Specified by:
simplify in interface Expression
Specified by:
simplify in class Instruction
Returns:
the simplified expression
Throws:
XPathException - if an error is discovered during expression rewriting

analyze

public Expression analyze(StaticContext env,
                          ItemType contextItemType)
                   throws XPathException
Perform static analysis of an expression and its subexpressions.

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 will only be accurately known if they have been explicitly declared.

Specified by:
analyze in interface Expression
Specified by:
analyze in class Instruction
Parameters:
env - the static context of the expression
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)

iterateSubExpressions

public java.util.Iterator 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)

Specified by:
iterateSubExpressions in interface Expression
Overrides:
iterateSubExpressions in class ComputedExpression
Returns:
an iterator containing the sub-expressions of this expression

promoteInst

protected void promoteInst(PromotionOffer offer)
                    throws XPathException
Handle promotion offers, that is, non-local tree rewrites.

Overrides:
promoteInst in class Instruction
Parameters:
offer - The type of rewrite being offered
Throws:
XPathException

process

public void process(XPathContext context)
             throws XPathException
Process this instruction, without leaving any tail calls.

Specified by:
process in interface Expression
Overrides:
process in class Instruction
Parameters:
context - the dynamic context for this transformation
Throws:
XPathException - if a dynamic error occurs

processLeavingTail

public TailCall processLeavingTail(XPathContext context)
                            throws XPathException
Process this instruction. If the called template contains a tail call (which may be an xsl:call-template of xsl:apply-templates instruction) then the tail call will not actually be evaluated, but will be returned in a TailCall object for the caller to execute.

Specified by:
processLeavingTail in class Instruction
Parameters:
context - the dynamic context for this transformation
Returns:
an object containing information about the tail call to be executed by the caller. Returns null if there is no tail call.
XPathException

getTargetTemplate

public Template getTargetTemplate(XPathContext context)
                           throws XPathException
Get the template, in the case where it is specified dynamically.

Parameters:
context - The dynamic context of the transformation
Returns:
The template to be called
Throws:
XPathException - if a dynamic error occurs: specifically, if the template name is computed at run-time (Saxon extension) and the name is invalid or does not reference a known template

display

public void display(int level,
                    NamePool pool,
                    java.io.PrintStream out)
Diagnostic print of expression structure. The expression is written to the System.err output stream

Parameters:
level - indentation level for this expression
out -
pool - NamePool used to expand any names appearing in the expression