Class Attribute

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

public final class Attribute extends SimpleNodeConstructor
An instruction derived from an xsl:attribute element in stylesheet, or from an attribute constructor in XQuery
See Also:
  • Constructor Details

    • Attribute

      public Attribute(Expression attributeName, Expression namespace, NamespaceResolver nsContext, int validationAction, SimpleType schemaType, int annotation, boolean allowNameAsQName)
      Construct an Attribute instruction
      Parameters:
      attributeName - An expression to calculate the attribute name
      namespace - An expression to calculate the attribute namespace
      nsContext - a NamespaceContext object containing the static namespace context of the stylesheet instruction
      validationAction - e.g. validation=strict, lax, strip, preserve
      schemaType - Type against which the attribute must be validated. This must not be a namespace-sensitive type; it is the caller's responsibility to check this.
      annotation - Integer code identifying the type named in the type attribute
      allowNameAsQName -
  • Method Details

    • setRejectDuplicates

      public void setRejectDuplicates()
      Indicate that two attributes with the same name are not acceptable. (This option is set in XQuery, but not in XSLT)
    • getInstructionNameCode

      public int getInstructionNameCode()
      Get the name of this instruction
      Overrides:
      getInstructionNameCode in class Instruction
    • getItemType

      public ItemType getItemType(TypeHierarchy th)
      Description copied from class: Instruction
      Get the item type of the items returned by evaluating this instruction
      Specified by:
      getItemType in interface Expression
      Overrides:
      getItemType in class Instruction
      Parameters:
      th -
      Returns:
      the static item type of the instruction
    • getCardinality

      public int getCardinality()
      Description copied from class: ComputedExpression
      Determine the static cardinality of the expression. This establishes how many items there will be in the result of the expression, at compile time (i.e., without actually evaluating the result.
      Specified by:
      getCardinality in interface Expression
      Overrides:
      getCardinality in class ComputedExpression
      Returns:
      one of the values Cardinality.ONE_OR_MORE, Cardinality.ZERO_OR_MORE, Cardinality.EXACTLY_ONE, Cardinality.ZERO_OR_ONE, Cardinality.EMPTY. This default implementation returns ZERO_OR_MORE (which effectively gives no information).
    • computeSpecialProperties

      public int computeSpecialProperties()
      Get the static properties of this expression (other than its type). The result is bit-signficant. These properties are used for optimizations. In general, if property bit is set, it is true, but if it is unset, the value is unknown.
      Overrides:
      computeSpecialProperties in class SimpleNodeConstructor
      Returns:
      a set of flags indicating static properties of this expression
    • simplify

      public Expression simplify(StaticContext env) throws XPathException
      Description copied from class: Instruction
      Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression). The default implementation does nothing.
      Specified by:
      simplify in interface Expression
      Overrides:
      simplify in class SimpleNodeConstructor
      Parameters:
      env - the static context
      Returns:
      the simplified expression
      Throws:
      XPathException - if an error is discovered during expression rewriting
    • localTypeCheck

      public void localTypeCheck(StaticContext env, ItemType contextItemType) throws XPathException
      Specified by:
      localTypeCheck in class SimpleNodeConstructor
      Throws:
      XPathException
    • iterateSubExpressions

      public Iterator iterateSubExpressions()
      Get the subexpressions of this expression
      Specified by:
      iterateSubExpressions in interface Expression
      Overrides:
      iterateSubExpressions in class SimpleNodeConstructor
      Returns:
      an iterator over the subexpressions
    • replaceSubExpression

      public boolean replaceSubExpression(Expression original, Expression replacement)
      Replace one subexpression by a replacement subexpression
      Specified by:
      replaceSubExpression in interface Container
      Overrides:
      replaceSubExpression in class SimpleNodeConstructor
      Parameters:
      original - the original subexpression
      replacement - the replacement subexpression
      Returns:
      true if the original subexpression is found
    • promoteInst

      protected void promoteInst(PromotionOffer offer) throws XPathException
      Offer promotion for subexpressions. The offer will be accepted if the subexpression is not dependent on the factors (e.g. the context item) identified in the PromotionOffer. By default the offer is not accepted - this is appropriate in the case of simple expressions such as constant values and variable references where promotion would give no performance advantage. This method is always called at compile time.
      Overrides:
      promoteInst in class SimpleNodeConstructor
      Parameters:
      offer - details of the offer, for example the offer to move expressions that don't depend on the context to an outer level in the containing expression
      Throws:
      XPathException - if any error is detected
    • checkPermittedContents

      public void checkPermittedContents(SchemaType parentType, StaticContext env, boolean whole) throws XPathException
      Check that any elements and attributes constructed or returned by this expression are acceptable in the content model of a given complex type. It's always OK to say yes, since the check will be repeated at run-time. The process of checking element and attribute constructors against the content model of a complex type also registers the type of content expected of those constructors, so the static validation can continue recursively.
      Specified by:
      checkPermittedContents in interface Expression
      Overrides:
      checkPermittedContents in class ComputedExpression
      Parameters:
      parentType - The schema type
      env - the static context
      whole - true if this expression is expected to make the whole content of the type, false if it is expected to make up only a part
      Throws:
      XPathException - if the expression doesn't match the required content type
    • processLeavingTail

      public TailCall processLeavingTail(XPathContext context) throws XPathException
      Process this instruction
      Specified by:
      processLeavingTail in interface TailCallReturner
      Specified by:
      processLeavingTail in class Instruction
      Parameters:
      context - the dynamic context of the transformation
      Returns:
      a TailCall to be executed by the caller, always null for this instruction
      Throws:
      XPathException
    • evaluateNameCode

      public int evaluateNameCode(XPathContext context) throws XPathException, XPathException
      Overrides:
      evaluateNameCode in class SimpleNodeConstructor
      Throws:
      XPathException
    • display

      public void display(int level, PrintStream out, Configuration config)
      Display this instruction as an expression, for diagnostics
      Specified by:
      display in interface Expression
      Overrides:
      display in class SimpleNodeConstructor
      Parameters:
      level - indentation level for this expression
      out - Output destination
      config -