|
||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | |||||||||
java.lang.Objectnet.sf.saxon.expr.ComputedExpression
net.sf.saxon.expr.UnaryExpression
net.sf.saxon.expr.CardinalityChecker
A CardinalityChecker implements the cardinality checking of "treat as": that is, it returns the supplied sequence, checking that its cardinality is correct
| Field Summary |
| Fields inherited from class net.sf.saxon.expr.UnaryExpression |
operand |
| Fields inherited from class net.sf.saxon.expr.ComputedExpression |
locationId, staticProperties |
| Fields inherited from interface net.sf.saxon.expr.Expression |
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD |
| Method Summary | |
int |
computeCardinality()
Determine the static cardinality of the expression |
int |
computeSpecialProperties()
Get the static properties of this expression (other than its type). |
java.lang.String |
depictSequenceStart(SequenceIterator seq,
int max)
Show the first couple of items in a sequence in an error message |
java.lang.String |
displayOperator(Configuration config)
Diagnostic print of expression structure |
boolean |
equals(java.lang.Object other)
Is this expression the same as another expression? |
Item |
evaluateItem(XPathContext context)
Evaluate as an Item. |
int |
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process(). |
ItemType |
getItemType(TypeHierarchy th)
Determine the data type of the items returned by the expression, if possible |
int |
getRequiredCardinality()
Get the required cardinality |
SequenceIterator |
iterate(XPathContext context)
Iterate over the sequence of values |
static ComputedExpression |
makeCardinalityChecker(Expression sequence,
int cardinality,
RoleLocator role)
Factory method to construct a CardinalityChecker. |
Expression |
optimize(Optimizer opt,
StaticContext env,
ItemType contextItemType)
Perform optimisation of an expression and its subexpressions. |
void |
process(XPathContext context)
Process the instruction, without returning any tail calls |
void |
setErrorCode(java.lang.String code)
Set the error code to be returned (this is used when evaluating the functions such as exactly-one() which have their own error codes) |
Expression |
typeCheck(StaticContext env,
ItemType contextItemType)
Type-check the expression |
| Methods inherited from class net.sf.saxon.expr.UnaryExpression |
display, getBaseExpression, hashCode, iterateSubExpressions, promote, replaceSubExpression, simplify |
| Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait |
| Method Detail |
public static ComputedExpression makeCardinalityChecker(Expression sequence,
int cardinality,
RoleLocator role)
sequence - cardinality - role -
public int getRequiredCardinality()
public Expression typeCheck(StaticContext env,
ItemType contextItemType)
throws XPathException
typeCheck in interface ExpressiontypeCheck in class UnaryExpressionXPathException
public Expression optimize(Optimizer opt,
StaticContext env,
ItemType contextItemType)
throws XPathException
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 interface Expressionoptimize in class UnaryExpressionopt - the optimizer in use. This provides access to supporting functions; it also allows
different optimization strategies to be used in different circumstances.env - the static context of the expressioncontextItemType - 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
StaticError - if an error is discovered during this phase
(typically a type error)
XPathExceptionpublic void setErrorCode(java.lang.String code)
public int getImplementationMethod()
getImplementationMethod in interface ExpressiongetImplementationMethod in class ComputedExpression
public SequenceIterator iterate(XPathContext context)
throws XPathException
iterate in interface Expressioniterate in class ComputedExpressioncontext - supplies the context for evaluation
XPathException - if any dynamic error occurs evaluating the
expression
public java.lang.String depictSequenceStart(SequenceIterator seq,
int max)
public Item evaluateItem(XPathContext context)
throws XPathException
evaluateItem in interface ExpressionevaluateItem in class ComputedExpressioncontext - The context in which the expression is to be evaluated
XPathException - if any dynamic error occurs evaluating the
expression
public void process(XPathContext context)
throws XPathException
process in interface Expressionprocess in class ComputedExpressioncontext - The dynamic context, giving access to the current node,
the current variables, etc.
XPathExceptionpublic ItemType getItemType(TypeHierarchy th)
getItemType in interface ExpressiongetItemType in class UnaryExpressionth -
public int computeCardinality()
computeCardinality in class UnaryExpressionpublic int computeSpecialProperties()
computeSpecialProperties in class UnaryExpressionpublic boolean equals(java.lang.Object other)
equals in class UnaryExpressionpublic java.lang.String displayOperator(Configuration config)
displayOperator in class UnaryExpressionconfig -
|
||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | |||||||||