Class UntypedAtomicConverter

All Implemented Interfaces:
Serializable, SourceLocator, Container, Expression, InstructionInfoProvider

public final class UntypedAtomicConverter extends UnaryExpression
An UntypedAtomicConverter is an expression that converts any untypedAtomic items in a sequence to a specified type
See Also:
  • Constructor Details

    • UntypedAtomicConverter

      public UntypedAtomicConverter(Expression sequence, AtomicType requiredItemType, boolean allConverted)
      Constructor
      Parameters:
      sequence - this must be a sequence of atomic values. This is not checked; a ClassCastException will occur if the precondition is not satisfied.
      requiredItemType - the item type to which untypedAtomic items in the sequence should be converted, using the rules for "cast as".
      allConverted - true if the result of this expression is a sequence in which all items belong to the required type
  • Method Details

    • getItemType

      public ItemType getItemType(TypeHierarchy th)
      Determine the data type of the items returned by the expression
      Specified by:
      getItemType in interface Expression
      Overrides:
      getItemType in class UnaryExpression
      Parameters:
      th -
      Returns:
      the item type of the items in the result sequence, insofar as this is known statically.
    • typeCheck

      public Expression typeCheck(StaticContext env, ItemType contextItemType) throws XPathException
      Type-check the expression
      Specified by:
      typeCheck in interface Expression
      Overrides:
      typeCheck in class UnaryExpression
      Parameters:
      env - the static context of the expression
      contextItemType - 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
      Returns:
      the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
      Throws:
      XPathException
    • computeSpecialProperties

      public int computeSpecialProperties()
      Determine the special properties of this expression
      Overrides:
      computeSpecialProperties in class UnaryExpression
      Returns:
      StaticProperty.NON_CREATIVE.
    • iterate

      public SequenceIterator iterate(XPathContext context) throws XPathException
      Iterate over the sequence of values
      Specified by:
      iterate in interface Expression
      Overrides:
      iterate in class ComputedExpression
      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
    • evaluateItem

      public Item evaluateItem(XPathContext context) throws XPathException
      Evaluate as an Item. This should only be called if the UntypedAtomicConverter has cardinality zero-or-one
      Specified by:
      evaluateItem in interface Expression
      Overrides:
      evaluateItem in class ComputedExpression
      Parameters:
      context - The context in which the expression is to be evaluated
      Returns:
      the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
      Throws:
      XPathException - if any dynamic error occurs evaluating the expression
    • displayOperator

      protected String displayOperator(Configuration config)
      Give a string representation of the operator for use in diagnostics
      Specified by:
      displayOperator in class UnaryExpression
      Parameters:
      config -
      Returns:
      the operator, as a string