ch.ethz.mxquery.iterators.forseq
Class ForseqWindowIterator

java.lang.Object
  ch.ethz.mxquery.model.Iterator
      ch.ethz.mxquery.model.TokenBasedIterator
          ch.ethz.mxquery.iterators.forseq.ForseqIterator
              ch.ethz.mxquery.iterators.forseq.ForseqWindowIterator

All Implemented Interfaces:

XDMIterator, Traversable

Direct Known Subclasses:

ForseqWindowEarlyBinding, ForseqWindowEarlyBindingParallel, ForseqWindowIndexIterator, ForseqWindowNaiveIterator

public abstract class ForseqWindowIterator
extends ForseqIterator

Basic helper class for all windows. As every window implementation has some stuff in common, this class was introduced

Field Summary

Fields inherited from class ch.ethz.mxquery.iterators.forseq.ForseqIterator

GENERAL_WINDOW, LANDMARK_WINDOW, ORDER_MODE_END, ORDER_MODE_ENDSTART, ORDER_MODE_NONE, SLIDING_WINDOW, TUMBLING_WINDOW

Fields inherited from interface ch.ethz.mxquery.model.XDMIterator

EXPR_CATEGORY_SEQUENTIAL, EXPR_CATEGORY_SIMPLE, EXPR_CATEGORY_UPDATING, EXPR_CATEGORY_VACUOUS, EXPR_PARAM_CHEAPEVAL, EXPR_PARAM_VARIABLE, EXPR_PARAM_WINDOW, EXPR_PARAM_XDMGEN

Constructor Summary

ForseqWindowIterator(Context ctx, int windowType, QName var, TypeInfo type, XDMIterator seq, WindowVariable[] startVars, XDMIterator startExpr, WindowVariable[] endVars, XDMIterator endExpr, boolean forceEnd, boolean onNewStart, int orderMode, QueryLocation location)
Creates a new Window Iterator

Method Summary

XDMIterator[]	getAllSubIters()
QName[]	getForseqVars() Get the name of all variables (possibly) bound by this Forseq window iterator instance
Context	getInnermostContext()
void	setContext(Context context, boolean recursive) Assigns a context for this iterator (and possibly for its subIterators), replacing the existing context
void	setResettable(boolean r) Set this Iterator (and its subiterators) resetable.
KXmlSerializer	traverseIteratorTree(KXmlSerializer serializer)
void	updateVarHolders(XQDynamicContext ctx) Set the variable holder using this context Access is public, since for parallel execution each new binding goes into new varHolders

Methods inherited from class ch.ethz.mxquery.iterators.forseq.ForseqIterator

copy, getForseqVariable, isParallelAccess, next, setParallelAccess

Methods inherited from class ch.ethz.mxquery.model.Iterator

addPredicates, close, copyInts, copyIterators, copyQNames, copyStrings, copyTypeInfos, getAllSubItersRecursive, getContext, getExpressionCategoryType, getLoc, getPendingUpdateList, getPredicates, getStaticType, getSubIters, hasPredicates, isConstModePreserve, isExprParameter, isOpen, isResettable, removePredicates, reset, setConstModePreserve, setLoc, setOrderByExpr, setParam, setReturnExpr, setSubIters, setSubIters, setSubIters, setWhereExpr, traverse

Methods inherited from class java.lang.Object

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

Constructor Detail

ForseqWindowIterator

public ForseqWindowIterator(Context ctx,
                            int windowType,
                            QName var,
                            TypeInfo type,
                            XDMIterator seq,
                            WindowVariable[] startVars,
                            XDMIterator startExpr,
                            WindowVariable[] endVars,
                            XDMIterator endExpr,
                            boolean forceEnd,
                            boolean onNewStart,
                            int orderMode,
                            QueryLocation location)
                     throws MXQueryException

Creates a new Window Iterator

Parameters:

windowType - Type of the window

var - Variable QName

type - Type of the variable (not supported at the moment)

seq - The source iterator

startVars - List of all start WindowVariables

startExpr - The start expression iterator

endVars - List of all end WindowVariables

endExpr - The end expression iterator

forceEnd - If a force of the end should be applied

onNewStart - If the end expressions is newstart

orderMode - Order mode of the iterator

Throws:

MXQueryException

Method Detail

setContext

public void setContext(Context context,
                       boolean recursive)
                throws MXQueryException

Description copied from interface: XDMIterator

Assigns a context for this iterator (and possibly for its subIterators), replacing the existing context

Specified by:

setContext in interface XDMIterator

Overrides:

setContext in class Iterator

Parameters:

context - the context to assign

recursive - true perform the assignment also subiteratos, false only replace on the current iterator

Throws:

MXQueryException

setResettable

public void setResettable(boolean r)
                   throws MXQueryException

Description copied from interface: XDMIterator

Set this Iterator (and its subiterators) resetable. Resetable iterators may require more space (trading buffered data against recomputation)

Specified by:

setResettable in interface XDMIterator

Overrides:

setResettable in class Iterator

Parameters:

r - true make this iterator resetable, false make it not resetable

Throws:

MXQueryException

getAllSubIters

public XDMIterator[] getAllSubIters()

Specified by:

getAllSubIters in interface XDMIterator

Overrides:

getAllSubIters in class Iterator

traverseIteratorTree

public KXmlSerializer traverseIteratorTree(KXmlSerializer serializer)
                                    throws java.lang.Exception

Specified by:

traverseIteratorTree in interface XDMIterator

Overrides:

traverseIteratorTree in class Iterator

Throws:

java.lang.Exception

getInnermostContext

public Context getInnermostContext()

updateVarHolders

public void updateVarHolders(XQDynamicContext ctx)
                      throws MXQueryException

Set the variable holder using this context Access is public, since for parallel execution each new binding goes into new varHolders

Parameters:

ctx - Context from which to resolve the variables into varHolders

Throws:

MXQueryException

getForseqVars

public QName[] getForseqVars()

Get the name of all variables (possibly) bound by this Forseq window iterator instance

Returns:

a sequence of variable names