Package net.sf.saxon.expr
Class EmptyTextNodeRemover
- java.lang.Object
-
- net.sf.saxon.expr.Expression
-
- net.sf.saxon.expr.UnaryExpression
-
- net.sf.saxon.expr.EmptyTextNodeRemover
-
- All Implemented Interfaces:
ExportAgent,ItemMappingFunction,Locatable,IdentityComparable,Traceable
public class EmptyTextNodeRemover extends UnaryExpression implements ItemMappingFunction
This class performs part of the processing in "constructing simple content": it takes an input sequence and eliminates empty text nodes into one.- Since:
- 9.3
-
-
Field Summary
-
Fields inherited from class net.sf.saxon.expr.Expression
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, MAX_COST, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, UPDATE_METHOD, WATCH_METHOD
-
-
Constructor Summary
Constructors Constructor Description EmptyTextNodeRemover(Expression p0)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description intcomputeCardinality()Determine the static cardinality.Expressioncopy(RebindingMap rebindings)Copy an expression.java.lang.StringgetExpressionName()Get a name identifying the kind of expression, in terms meaningful to a user.intgetImplementationMethod()An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().ItemTypegetItemType()Determine the data type of the expression, if possible.protected OperandRolegetOperandRole()Get the usage (in terms of streamability analysis) of the single operandjava.lang.StringgetStreamerName()Get the (partial) name of a class that supports streaming of this kind of expressionSequenceIteratoriterate(XPathContext context)Return an Iterator to iterate over the values of a sequence.ItemmapItem(Item item)Map an item to another item-
Methods inherited from class net.sf.saxon.expr.UnaryExpression
computeHashCode, computeSpecialProperties, displayOperator, emitExtraAttributes, equals, export, getBaseExpression, getOperand, operands, optimize, setBaseExpression, toShortString, toString, typeCheck
-
Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, evaluatePendingUpdates, explain, getCardinality, getConfiguration, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getIntrinsicDependencies, getLocalRetainedStaticContext, getLocation, getNetCost, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, getTracingTag, hasCompatibleStaticContext, hashCode, hasSpecialProperty, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isEqual, isIdentical, isInstruction, isLiftable, isMultiThreaded, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimizeChildren, prepareForStreaming, process, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, typeCheckChildren, typeError, unordered, verifyParentPointers
-
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
-
Methods inherited from interface net.sf.saxon.trace.Traceable
gatherProperties
-
-
-
-
Constructor Detail
-
EmptyTextNodeRemover
public EmptyTextNodeRemover(Expression p0)
-
-
Method Detail
-
getItemType
public ItemType getItemType()
Determine the data type of the expression, if possible. The default implementation for unary expressions returns the item type of the operand- Overrides:
getItemTypein classUnaryExpression- Returns:
- the item type of the items in the result sequence, insofar as this is known statically.
-
computeCardinality
public int computeCardinality()
Description copied from class:UnaryExpressionDetermine the static cardinality. Default implementation returns the cardinality of the operand- Overrides:
computeCardinalityin classUnaryExpression- Returns:
- the computed cardinality, as one of the values
StaticProperty.ALLOWS_ZERO_OR_ONE,StaticProperty.EXACTLY_ONE,StaticProperty.ALLOWS_ONE_OR_MORE,StaticProperty.ALLOWS_ZERO_OR_MORE. May also returnStaticProperty.ALLOWS_ZEROif the result is known to be an empty sequence, orStaticProperty.ALLOWS_MANYif if is known to return a sequence of length two or more.
-
getOperandRole
protected OperandRole getOperandRole()
Description copied from class:UnaryExpressionGet the usage (in terms of streamability analysis) of the single operand- Specified by:
getOperandRolein classUnaryExpression- Returns:
- the operand usage
-
copy
public Expression copy(RebindingMap rebindings)
Copy an expression. This makes a deep copy.- Specified by:
copyin classExpression- Parameters:
rebindings-- 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 prefered.- Specified by:
getImplementationMethodin classExpression- Returns:
- the implementation method, for example
Expression.ITERATE_METHODorExpression.EVALUATE_METHODorExpression.PROCESS_METHOD
-
iterate
public SequenceIterator iterate(XPathContext context) throws XPathException
Return an Iterator to iterate over the values of a sequence. The value of every expression can be regarded as a sequence, so this method is supported for all expressions. This default implementation handles iteration for expressions that return singleton values: for non-singleton expressions, the subclass must provide its own implementation.- Overrides:
iteratein classExpression- 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
-
mapItem
public Item mapItem(Item item) throws XPathException
Map an item to another item- Specified by:
mapItemin interfaceItemMappingFunction- Parameters:
item- The input item to be mapped.- Returns:
- the result of the mapping: maybe null
- Throws:
XPathException
-
getStreamerName
public java.lang.String getStreamerName()
Get the (partial) name of a class that supports streaming of this kind of expression- Overrides:
getStreamerNamein classExpression- Returns:
- the partial name of a class that can be instantiated to provide streaming support in Saxon-EE, or null if there is no such class
-
getExpressionName
public java.lang.String getExpressionName()
Description copied from class:ExpressionGet a name identifying the kind of expression, in terms meaningful to a user.- Overrides:
getExpressionNamein classExpression- Returns:
- a name identifying the kind of expression, in terms meaningful to a user. The name will always be in the form of a lexical XML QName, and should match the name used in export() output displaying the expression.
-
-