net.sf.saxon.instruct
Class UseAttributeSets
- SourceLocator, EvaluableItem, InstructionInfoProvider, SequenceIterable, Serializable, SourceLocator, TailCallReturner
public class UseAttributeSets
This instruction corresponds to a use-attribute-sets attribute on a literal result element, xsl:element,
or xsl:copy.
assembleParams , assembleTunnelParams , computeCardinality , computeSpecialProperties , createsNewNodes , dynamicError , evaluateAsString , evaluateItem , getImplementationMethod , getInstructionInfo , getInstructionNameCode , getItemType , getSourceLocator , isXSLT , iterate , process , processLeavingTail , promote , promoteInst , simplify |
addToPathMap , adoptChildExpression , checkPermittedContents , computeCardinality , computeDependencies , computeSpecialProperties , computeStaticProperties , copy , display , doPromotion , dynamicError , effectiveBooleanValue , evaluateAsString , evaluateItem , explain , explain , findParentOf , getCardinality , getColumnNumber , getConstructType , getContainer , getDependencies , getExecutable , getHostLanguage , getImplementationMethod , getInstructionInfo , getIntrinsicDependencies , getItemType , getLineNumber , getLocationId , getLocationProvider , getPublicId , getSlotsUsed , getSpecialProperties , getSystemId , hasLoopingSubexpression , implementsStaticTypeCheck , iterate , iterateEvents , iterateSubExpressions , markTailFunctionCalls , optimize , process , promote , replaceSubExpression , resetLocalStaticProperties , setContainer , setFiltered , setFlattened , setLocationId , simplify , staticTypeCheck , suppressValidation , toString , typeCheck , typeError |
UseAttributeSets
public UseAttributeSets(AttributeSet[] sets)
Create a use-attribute-sets expression
sets
- the set of attribute sets to be expanded
copy
public Expression copy()
Copy an expression. This makes a deep copy.
- copy in interface Expression
- the copy of the original expression
explain
public void explain(ExpressionPresenter out)
Diagnostic print of expression structure. The abstract expression tree
is written to the supplied output destination.
- explain in interface Expression
getIntrinsicDependencies
public int getIntrinsicDependencies()
Determine the intrinsic dependencies of an expression, that is, those which are not derived
from the dependencies of its subexpressions. For example, position() has an intrinsic dependency
on the context position, while (position()+1) does not. The default implementation
of the method returns 0, indicating "no dependencies".
- getIntrinsicDependencies in interface Expression
- a set of bit-significant flags identifying the "intrinsic"
dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty
getItemType
public ItemType getItemType(TypeHierarchy th)
Get the item type of the items returned by evaluating this instruction
- getItemType in interface Instruction
th
- the type hierarchy cache
- the static item type of the instruction
optimize
public Expression optimize(ExpressionVisitor visitor,
ItemType contextItemType)
throws XPathException
Perform optimisation of an expression and its subexpressions.
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 Expression
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 to
Type.ITEM_TYPE
- the original expression, rewritten if appropriate to optimize execution
XPathException
- if an error is discovered during this phase
(typically a type error)
processLeavingTail
public TailCall processLeavingTail(XPathContext context)
throws XPathException
ProcessLeavingTail: called to do the real work of this instruction. This method
must be implemented in each subclass. The results of the instruction are written
to the current Receiver, which can be obtained via the Controller.
- processLeavingTail in interface TailCallReturner
- processLeavingTail in interface Instruction
context
- The dynamic context of the transformation, giving access to the current node,
the current variables, etc.
- null if the instruction has completed execution; or a TailCall indicating
a function call or template call that is delegated to the caller, to be made after the stack has
been unwound so as to save stack space.
simplify
public Expression simplify(ExpressionVisitor visitor)
throws XPathException
Simplify an expression. This performs any static optimization (by rewriting the expression
as a different expression). The default implementation does nothing.
- simplify in interface Instruction
visitor
- an expression visitor
- the simplified expression
XPathException
- if an error is discovered during expression
rewriting
typeCheck
public Expression typeCheck(ExpressionVisitor visitor,
ItemType contextItemType)
throws XPathException
Perform type checking of an expression and its subexpressions.
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 interface Expression
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 to
Type.ITEM_TYPE
- the original expression, rewritten to perform necessary
run-time type checks, and to perform other type-related
optimizations
XPathException
- if an error is discovered during this phase
(typically a type error)