public class ConditionalBlock extends Instruction
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, UPDATE_METHOD, WATCH_METHOD
Constructor and Description |
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ConditionalBlock(Expression[] children)
Create a block, supplying its child expressions
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ConditionalBlock(java.util.List<Expression> children)
Create a block, supplying its child expressions
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Modifier and Type | Method and Description |
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void |
checkPermittedContents(SchemaType parentType,
boolean whole)
Check that any elements and attributes constructed or returned by this expression are acceptable
in the content model of a given complex type.
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int |
computeSpecialProperties()
Get the static properties of this expression (other than its type).
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Expression |
copy(RebindingMap rebindings)
Copy an expression.
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void |
export(ExpressionPresenter out)
Diagnostic print of expression structure.
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int |
getCardinality()
Determine the cardinality of the expression
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Expression |
getChildExpression(int n)
Get the n'th child expression
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Expression[] |
getChildren()
Deprecated.
since 9.7 - use the operands() iterator instead
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java.lang.String |
getExpressionName()
Get a name identifying the kind of expression, in terms meaningful to a user.
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int |
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
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ItemType |
getItemType()
Determine the data type of the items returned by this expression
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java.lang.String |
getStreamerName()
Get the (partial) name of a class that supports streaming of this kind of expression
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boolean |
mayCreateNewNodes()
Determine whether this instruction creates new nodes.
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java.lang.Iterable<Operand> |
operands()
Get the immediate sub-expressions of this expression, with information about the relationship
of each expression to its parent expression.
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Expression |
optimize(ExpressionVisitor visitor,
ContextItemStaticInfo contextInfo)
Perform optimisation of an expression and its subexpressions.
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TailCall |
processLeavingTail(XPathContext context)
ProcessLeavingTail: called to do the real work of this instruction.
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int |
size()
Get the number of children
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java.lang.String |
toShortString()
Produce a short string identifying the expression for use in error messages
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Expression |
typeCheck(ExpressionVisitor visitor,
ContextItemStaticInfo contextInfo)
Perform type checking of an expression and its subexpressions.
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alwaysCreatesNewNodes, assembleParams, assembleTunnelParams, computeCardinality, dynamicError, evaluateAsString, evaluateItem, getConstructType, getInstructionName, getInstructionNameCode, getNetCost, getSourceLocator, isInstruction, isXSLT, iterate, process, someOperandCreatesNewNodes
addToPathMap, adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, computeDependencies, computeHashCode, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluatePendingUpdates, explain, getConfiguration, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getIntrinsicDependencies, getLocalRetainedStaticContext, getLocation, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, hasCompatibleStaticContext, hashCode, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isCallOnSystemFunction, isIdentical, isLiftable, isMultiThreaded, isSameExpression, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimizeChildren, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, toString, typeCheckChildren, typeError, unordered, verifyParentPointers, verifyParentPointers
public ConditionalBlock(Expression[] children)
children
- the child expressions in orderpublic ConditionalBlock(java.util.List<Expression> children)
children
- the child expressions in orderpublic Expression getChildExpression(int n)
n
- the position of the child expression required (zero-based)public int size()
public java.lang.Iterable<Operand> operands()
Expression
If the expression is a Callable, then it is required that the order of the operands returned by this function is the same as the order of arguments supplied to the corresponding call() method.
operands
in class Instruction
public java.lang.String getExpressionName()
Instruction
getExpressionName
in class Instruction
public Expression[] getChildren()
public int computeSpecialProperties()
Instruction
computeSpecialProperties
in class Instruction
public Expression copy(RebindingMap rebindings)
copy
in class Expression
rebindings
- variables to be reboundpublic final ItemType getItemType()
getItemType
in class Instruction
public final int getCardinality()
getCardinality
in class Expression
public final boolean mayCreateNewNodes()
mayCreateNewNodes
in class Instruction
public Expression typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathException
Expression
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.
typeCheck
in class Expression
visitor
- an expression visitorcontextInfo
- Information available statically about the context item: whether it is (possibly)
absent; its static type; its streaming posture.XPathException
- if an error is discovered during this phase
(typically a type error)public Expression optimize(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathException
Expression
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.
optimize
in class Expression
visitor
- an expression visitorcontextInfo
- 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
XPathException
- if an error is discovered during this phase
(typically a type error)public void checkPermittedContents(SchemaType parentType, boolean whole) throws XPathException
checkPermittedContents
in class Expression
parentType
- the "given complex type": the method is checking that the nodes returned by this
expression are acceptable members of the content model of this typewhole
- if true, we want to check that the value of this expression satisfies the content model
as a whole; if false we want to check that the value of the expression is acceptable as one part
of the contentXPathException
- if the value delivered by this expression cannot be part of the content model
of the given typepublic void export(ExpressionPresenter out) throws XPathException
export
in interface ExportAgent
export
in class Expression
out
- the expression presenter used to display the structureXPathException
- if the export fails, for example if an expression is found that won't work
in the target environment.public java.lang.String toShortString()
Expression
toShortString
in class Expression
public TailCall processLeavingTail(XPathContext context) throws XPathException
Instruction
processLeavingTail
in interface TailCallReturner
processLeavingTail
in class Instruction
context
- The dynamic context of the transformation, giving access to the current node,
the current variables, etc.XPathException
- if a dynamic error occurs during the evaluation
of the instructionpublic int getImplementationMethod()
getImplementationMethod
in class Instruction
Expression.ITERATE_METHOD
or Expression.EVALUATE_METHOD
or
Expression.PROCESS_METHOD
public java.lang.String getStreamerName()
getStreamerName
in class Expression
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