## com.saxonica.expr.ee
Class MultithreadedForEach

    java.lang.Object
      net.sf.saxon.expr.Expression
          net.sf.saxon.expr.instruct.Instruction
              net.sf.saxon.expr.instruct.ForEach
                  com.saxonica.expr.ee.MultithreadedForEach

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

    public class MultithreadedForEach

extends ForEach

This instruction represents an xsl:for-each instruction using more than one thread

See Also:
  Serialized Form

Field Summary

Fields inherited from class net.sf.saxon.expr.instruct.ForEach
`action, containsTailCall, select, threads`

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
`MultithreadedForEach(Expression select, Expression action, boolean containsTailCall, int threads)`

Method Summary
`Expression` `copy()` Copy an expression.
`protected void` `explainThreads(ExpressionPresenter out)` Add the value of the saxon:threads attribute to the explain output
`int` `getImplementationMethod()` An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
`SequenceIterator` `iterate(XPathContext context)` Return an Iterator to iterate over the values of the sequence.
`TailCall` `processLeavingTail(XPathContext context)` ProcessLeavingTail: called to do the real work of this instruction.

Methods inherited from class net.sf.saxon.expr.instruct.ForEach
`addToPathMap, checkPermittedContents, computeDependencies, createsNewNodes, explain, getActionExpression, getInstructionNameCode, getItemType, getNumberOfThreads, getSelectExpression, hasLoopingSubexpression, iterateSameFocusSubExpressions, iterateSubExpressions, map, optimize, promoteInst, replaceSubExpression, simplify, typeCheck`

Methods inherited from class net.sf.saxon.expr.instruct.Instruction
`assembleParams, assembleTunnelParams, computeCardinality, computeSpecialProperties, dynamicError, evaluateAsString, evaluateItem, getConstructType, getExpressionName, getInstructionName, getIteratorFromProcessMethod, getSourceLocator, isXSLT, process, promote`

Methods inherited from class net.sf.saxon.expr.Expression

`adoptChildExpression, checkForUpdatingSubexpressions, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, 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`

Constructor Detail

### MultithreadedForEach

    public MultithreadedForEach(Expression select,
                                Expression action,
                                boolean containsTailCall,
                                int threads)

Method Detail

### copy

    public Expression copy()

  Copy an expression. This makes a deep copy.

  Overrides:
    `copy` in class `ForEach`
  Returns:
    the copy of the original expression

### 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 provided. This implementation provides only the process() method natively.

  Overrides:
    `getImplementationMethod` in class `ForEach`
  Returns:
    the implementation method, for example `Expression.ITERATE_METHOD` or `Expression.EVALUATE_METHOD` or `Expression.PROCESS_METHOD`

### 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`
  Overrides:
    `processLeavingTail` in class `ForEach`
  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`

### iterate

    public SequenceIterator iterate(XPathContext context)
                             throws XPathException

  Return an Iterator to iterate over the values of the sequence.

  Specified by:
    `iterate` in interface `SequenceIterable`
  Overrides:
    `iterate` in class `ForEach`
  Parameters:
    `context` - supplies the context for evaluation
  Returns:
    a SequenceIterator that can be used to iterate over the result of the expression
  Throws:
    `XPathException` - if any dynamic error occurs evaluating the expression

### explainThreads

    protected void explainThreads(ExpressionPresenter out)

  Add the value of the saxon:threads attribute to the explain output

  Overrides:
    `explainThreads` in class `ForEach`
  Parameters:
    `out` - the destination for explain output

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