## net.sf.saxon.expr.instruct
Class ApplyTemplates

    java.lang.Object
      net.sf.saxon.expr.Expression
          net.sf.saxon.expr.instruct.Instruction
              net.sf.saxon.expr.instruct.ApplyTemplates

All Implemented Interfaces:
  Serializable, SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, ITemplateCall, TailCallReturner, SequenceIterable, InstructionInfo, Locator

Direct Known Subclasses:
  StreamingApplyTemplates

    public class ApplyTemplates

extends Instruction
implements ITemplateCall

An instruction representing an xsl:apply-templates element in the stylesheet

See Also:
  Serialized Form

Field Summary
`protected WithParam[]` `actualParams`
`protected boolean` `implicitSelect`
`protected Mode` `mode`
`protected Expression` `select`
`protected WithParam[]` `tunnelParams`
`protected boolean` `useCurrentMode`
`protected boolean` `useTailRecursion`

Fields inherited from class net.sf.saxon.expr.Expression
`EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, PUSH_SELECTION, staticProperties, WATCH_METHOD`

Constructor Summary
`protected` `ApplyTemplates()`
`` `ApplyTemplates(Expression select, boolean useCurrentMode, boolean useTailRecursion, boolean implicitSelect, Mode mode)` Construct an apply-templates instructino

Method Summary
`PathMap.PathMapNodeSet` `addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)` Add a representation of this expression to a PathMap.
`protected TailCall` `apply(XPathContext context, boolean returnTailCall)`
`static TailCall` `applyTemplates(SequenceIterator iterator, Mode mode, ParameterSet parameters, ParameterSet tunnelParameters, XPathContextMajor context, int locationId)` Process selected nodes using the handlers registered for a particular mode.
`Expression` `copy()` Copy an expression.
`boolean` `createsNewNodes()` Determine whether this instruction creates new nodes.
`static void` `defaultAction(NodeInfo node, ParameterSet parameters, ParameterSet tunnelParams, XPathContext context, int locationId)` Perform the built-in template action for a given node.
`void` `explain(ExpressionPresenter out)` Diagnostic print of expression structure.
`protected void` `explainStreaming(ExpressionPresenter out)`
`WithParam[]` `getActualParams()` Get the actual parameters passed to the called template
`int` `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 purposes
`int` `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 Mode
`Expression` `getSelectExpression()` Get the select expression
`WithParam[]` `getTunnelParams()` Get the tunnel parameters passed to the called template
`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
`protected void` `init(Expression select, boolean useCurrentMode, boolean useTailRecursion, Mode mode)`
`boolean` `isImplicitSelect()` Ask if the select expression was implicit
`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, ItemType contextItemType)` Perform optimisation of an expression and its subexpressions.
`void` `process(XPathContext context)` Process the instruction, without returning any tail calls
`TailCall` `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 subexpression
`void` `setActualParameters(WithParam[] actualParams, WithParam[] tunnelParams)` Set the actual parameters on the call
`Expression` `simplify(ExpressionVisitor visitor)` Simplify an expression.
`Expression` `typeCheck(ExpressionVisitor visitor, ItemType contextItemType)` Perform type checking of an expression and its subexpressions.
`boolean` `usesCurrentMode()` Ask if mode="#current" was specified
`boolean` `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`

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, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toString, typeError`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Methods inherited from interface javax.xml.transform.SourceLocator
`getColumnNumber, getLineNumber, getPublicId, getSystemId`

Field Detail

### select

    protected Expression select

### actualParams

    protected WithParam[] actualParams

### tunnelParams

    protected WithParam[] tunnelParams

### useCurrentMode

    protected boolean useCurrentMode

### useTailRecursion

    protected boolean useTailRecursion

### mode

    protected Mode mode

### implicitSelect

    protected boolean implicitSelect

Constructor Detail

### ApplyTemplates

    protected ApplyTemplates()

### ApplyTemplates

    public ApplyTemplates(Expression select,
                          boolean useCurrentMode,
                          boolean useTailRecursion,
                          boolean implicitSelect,
                          Mode mode)

  Construct an apply-templates instructino

  Parameters:
    `select` - the select expression
    `useCurrentMode` - true if mode="#current" was specified
    `useTailRecursion` - true if this instruction is the last in its template
    `mode` - the mode specified on apply-templates

Method Detail

### init

    protected void init(Expression select,
                        boolean useCurrentMode,
                        boolean useTailRecursion,
                        Mode mode)

### 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"

### getInstructionNameCode

    public int getInstructionNameCode()

  Get the name of this instruction for diagnostic and tracing purposes

  Overrides:
    `getInstructionNameCode` in class `Instruction`
  Returns:
    a code identifying the instruction: typically but not always the fingerprint of a name in the XSLT namespace

### 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 class `Instruction`
  Returns:
    the implementation method, for example `Expression.ITERATE_METHOD` or `Expression.EVALUATE_METHOD` or `Expression.PROCESS_METHOD`

### 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 class `Instruction`
  Parameters:
    `visitor` - the expression visitor
  Returns:
    the simplified expression
  Throws:
    `XPathException` - if an error is discovered during expression rewriting

### typeCheck

    public Expression typeCheck(ExpressionVisitor visitor,
                                ItemType 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 class `Expression`
  Parameters:
    `visitor` - an expression visitor
    `contextItemType` - 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 to `Type.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)

### optimize

    public Expression optimize(ExpressionVisitor visitor,
                               ItemType 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 class `Expression`
  Parameters:
    `visitor` - an expression visitor
    `contextItemType` - 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 to `Type.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)

### 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 class `Expression`
  Returns:
    a set of bit-significant flags identifying the "intrinsic" dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty

### copy

    public Expression copy()

  Copy an expression. This makes a deep copy.

  Specified by:
    `copy` in class `Expression`
  Returns:
    the copy of the original expression

### 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 class `Instruction`
  Returns:
    true if the instruction creates new nodes (or if it can't be proved that it doesn't)

### process

    public void process(XPathContext context)
                 throws XPathException

  Description copied from class: `Instruction`
  Process the instruction, without returning any tail calls

  Overrides:
    `process` in class `Instruction`
  Parameters:
    `context` - The dynamic context, giving access to the current node, the current variables, etc.
  Throws:
    `XPathException`

### 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 interface `TailCallReturner`
  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.
  Throws:
    `XPathException`

### apply

    protected TailCall apply(XPathContext context,
                             boolean returnTailCall)
                      throws XPathException

  Throws:
    `XPathException`

### applyTemplates

    public static TailCall applyTemplates(SequenceIterator iterator,
                                          Mode mode,
                                          ParameterSet parameters,
                                          ParameterSet tunnelParameters,
                                          XPathContextMajor context,
                                          int locationId)
                                   throws XPathException

  Process selected nodes using the handlers registered for a particular mode.

  Parameters:
    `iterator` - an Iterator over the nodes to be processed, in the correct (sorted) order
    `mode` - Identifies the processing mode. It should match the mode defined when the element handler was registered using setHandler with a mode parameter. Set this parameter to null to invoke the default mode.
    `parameters` - A ParameterSet containing the parameters to the handler/template being invoked. Specify null if there are no parameters.
    `tunnelParameters` - A ParameterSet containing the parameters to the handler/template being invoked. Specify null if there are no parameters.
    `context` - A newly-created context object (this must be freshly created by the caller, as it will be modified by this method)
    `locationId` - location of this apply-templates instruction in the stylesheet
  Returns:
    a TailCall returned by the last template to be invoked, or null, indicating that there are no outstanding tail calls.
  Throws:
    `XPathException` - if any dynamic error occurs

### defaultAction

    public static void defaultAction(NodeInfo node,
                                     ParameterSet parameters,
                                     ParameterSet tunnelParams,
                                     XPathContext context,
                                     int locationId)
                              throws XPathException

  Perform the built-in template action for a given node.

  Parameters:
    `node` - the node to be processed
    `parameters` - the parameters supplied to apply-templates
    `tunnelParams` - the tunnel parameters to be passed through
    `context` - the dynamic evaluation context
    `locationId` - location of the instruction (apply-templates, apply-imports etc) that caused the built-in template to be invoked
  Throws:
    `XPathException` - if any dynamic error occurs

### iterateSubExpressions

    public 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 class `Expression`
  Returns:
    an iterator containing the sub-expressions of this expression

### 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 class `Expression`
  Parameters:
    `child` - the immediate subexpression
  Returns:
    true if the child expression is evaluated repeatedly

### replaceSubExpression

    public boolean replaceSubExpression(Expression original,
                                        Expression replacement)

  Replace one subexpression by a replacement subexpression

  Overrides:
    `replaceSubExpression` in class `Expression`
  Parameters:
    `original` - the original subexpression
    `replacement` - the replacement subexpression
  Returns:
    true if the original subexpression is found

### getSelectExpression

    public Expression getSelectExpression()

  Get the select expression

  Returns:
    the select expression

### isImplicitSelect

    public boolean isImplicitSelect()

  Ask if the select expression was implicit

  Returns:
    true if no select attribute was explicitly specified

### useTailRecursion

    public boolean useTailRecursion()

  Ask if tail recursion is to be used

  Returns:
    true if tail recursion is used

### usesCurrentMode

    public boolean usesCurrentMode()

  Ask if mode="#current" was specified

  Returns:
    true if mode="#current" was specified

### getMode

    public Mode getMode()

  Get the Mode

  Returns:
    the mode, or null if mode="#current" was specified

### getActualParams

    public WithParam[] getActualParams()

  Get the actual parameters passed to the called template

  Specified by:
    `getActualParams` in interface `ITemplateCall`
  Returns:
    the non-tunnel parameters

### getTunnelParams

    public WithParam[] getTunnelParams()

  Get the tunnel parameters passed to the called template

  Specified by:
    `getTunnelParams` in interface `ITemplateCall`
  Returns:
    the tunnel parameters

### 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`

### 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 class `Expression`
  Parameters:
    `pathMap` - the PathMap to which the expression should be added
    `pathMapNodeSet` - 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.

### 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 class `Expression`
  Parameters:
    `out` - output destination

### explainStreaming

    protected void explainStreaming(ExpressionPresenter out)

Copyright (c) 2004-2010 Saxonica Limited. All rights reserved.