Package net.sf.saxon.expr
Class GeneralComparison10
java.lang.Object
net.sf.saxon.expr.Expression
net.sf.saxon.expr.BinaryExpression
net.sf.saxon.expr.GeneralComparison10
- All Implemented Interfaces:
Serializable
,SourceLocator
,LocationProvider
,SaxonLocator
,CallableExpression
,InstructionInfo
,Locator
GeneralComparison10: a boolean expression that compares two expressions
for equals, not-equals, greater-than or less-than. This implements the operators
=, !=, invalid input: '<', >, etc. This version of the class implements general comparisons
in XPath 1.0 backwards compatibility mode, as defined in the Oct 2004 revision
of the specifications.
- See Also:
-
Field Summary
FieldsFields inherited from class net.sf.saxon.expr.BinaryExpression
operand0, operand1, operator
Fields inherited from class net.sf.saxon.expr.Expression
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, WATCH_METHOD
-
Constructor Summary
ConstructorsConstructorDescriptionGeneralComparison10
(Expression p0, int op, Expression p1) Create a general comparison identifying the two operands and the operator -
Method Summary
Modifier and TypeMethodDescriptioncall
(SequenceIterator[] arguments, XPathContext context) Evaluate the expression: interface for use by compiled bytecodeint
Determine the static cardinality.copy()
Copy an expression.boolean
effectiveBooleanValue
(XPathContext context) Evaluate the expression giving a boolean resultevaluateItem
(XPathContext context) Evaluate the expression in a given contextprotected void
Add subclass-specific attributes to the expression tree explanation.Determine the data type of the expressionoptimize
(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) Optimize the expressionvoid
setAtomicComparer
(AtomicComparer comparer) typeCheck
(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) Type-check the expressionMethods inherited from class net.sf.saxon.expr.BinaryExpression
computeSpecialProperties, displayOperator, equals, explain, getArguments, getOperands, getOperator, hashCode, isAssociative, isCommutative, isInverse, iterateSubExpressions, promote, replaceSubExpression, setFlattened, simplify, toString
Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getExpressionName, getHostLanguage, getImplementationMethod, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterate, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setLocationId, staticTypeCheck, suppressValidation, typeError
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
Methods inherited from interface net.sf.saxon.expr.CallableExpression
getArguments
-
Field Details
-
singletonOperator
protected int singletonOperator -
comparer
-
-
Constructor Details
-
GeneralComparison10
Create a general comparison identifying the two operands and the operator- Parameters:
p0
- the left-hand operandop
- the operator, as a token returned by the Tokenizer (e.g. Token.LT)p1
- the right-hand operand
-
-
Method Details
-
computeCardinality
public int computeCardinality()Determine the static cardinality. Returns [1..1]- Overrides:
computeCardinality
in classBinaryExpression
- 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
-
typeCheck
public Expression typeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException Type-check the expression- Overrides:
typeCheck
in classBinaryExpression
- Parameters:
visitor
- an expression visitorcontextItemType
- 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 toType.ITEM_TYPE
- Returns:
- the checked expression
- Throws:
XPathException
- if an error is discovered during this phase (typically a type error)
-
setAtomicComparer
-
optimize
public Expression optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException Optimize the expression- Overrides:
optimize
in classBinaryExpression
- Parameters:
visitor
- an expression visitorcontextItemType
- 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 toType.ITEM_TYPE
- Returns:
- the checked expression
- Throws:
XPathException
- if an error is discovered during this phase (typically a type error)
-
evaluateItem
Evaluate the expression in a given context- Overrides:
evaluateItem
in classExpression
- Parameters:
context
- the given context for evaluation- Returns:
- a BooleanValue representing the result of the numeric comparison of the two operands
- Throws:
XPathException
- if any dynamic error occurs evaluating the expression
-
call
public SequenceIterator call(SequenceIterator[] arguments, XPathContext context) throws XPathException Evaluate the expression: interface for use by compiled bytecode- Specified by:
call
in interfaceCallableExpression
- Parameters:
arguments
- the values of the arguments, supplied as SequenceIteratorscontext
- the dynamic evaluation context- Returns:
- the result of the evaluation, in the form of a SequenceIterator
- Throws:
XPathException
- if a dynamic error occurs during the evaluation of the expression
-
effectiveBooleanValue
Evaluate the expression giving a boolean result- Overrides:
effectiveBooleanValue
in classExpression
- Parameters:
context
- the given context for evaluation- Returns:
- a boolean representing the result of the comparison of the two operands
- Throws:
XPathException
- if any dynamic error occurs evaluating the expression
-
copy
Copy an expression. This makes a deep copy.- Specified by:
copy
in classExpression
- Returns:
- the copy of the original expression
-
getItemType
Determine the data type of the expression- Specified by:
getItemType
in classExpression
- Parameters:
th
- the type hierarchy cache- Returns:
- Type.BOOLEAN
-
explainExtraAttributes
Description copied from class:BinaryExpression
Add subclass-specific attributes to the expression tree explanation. Default implementation does nothing; this is provided for subclasses to override.- Overrides:
explainExtraAttributes
in classBinaryExpression
- Parameters:
out
- the output destination for the displayed expression tree
-