Class AnyFunctionType

  • All Implemented Interfaces:
    java.io.Serializable, FunctionItemType, ItemType

    public class AnyFunctionType
    extends java.lang.Object
    implements FunctionItemType
    An ItemType representing the type function(). Subtypes represent function items with more specific type signatures.
    See Also:
    Serialized Form
    • Constructor Detail

      • AnyFunctionType

        public AnyFunctionType()
    • Method Detail

      • getInstance

        public static AnyFunctionType getInstance()
        Get the singular instance of this type (Note however that subtypes of this type may have any number of instances)
      • isAtomicType

        public boolean isAtomicType()
        Determine whether this item type is an atomic type
        Specified by:
        isAtomicType in interface ItemType
        Returns:
        true if this is ANY_ATOMIC_TYPE or a subtype thereof
      • isPlainType

        public boolean isPlainType()
        Determine whether this item type is atomic (that is, whether it can ONLY match atomic values)
        Specified by:
        isPlainType in interface ItemType
        Returns:
        true if this is ANY_ATOMIC_TYPE or a subtype thereof
      • isMapType

        public boolean isMapType()
        Ask whether this function item type is a map type. In this case function coercion (to the map type) will never succeed.
        Specified by:
        isMapType in interface FunctionItemType
        Returns:
        true if this FunctionItemType is a map type
      • getArgumentTypes

        public SequenceType[] getArgumentTypes()
        Get the argument types of the function
        Specified by:
        getArgumentTypes in interface FunctionItemType
        Returns:
        the argument types, as an array of SequenceTypes, or null if this is the generic function type function(*)
      • matches

        public boolean matches​(Item item,
                               XPathContext context)
        Test whether a given item conforms to this type
        Specified by:
        matches in interface ItemType
        Parameters:
        item - The item to be tested
        context - the XPath dynamic evaluation context
        Returns:
        true if the item is an instance of this type; false otherwise
      • matchesItem

        public boolean matchesItem​(Item item,
                                   boolean allowURIPromotion,
                                   Configuration config)
        Test whether a given item conforms to this type
        Specified by:
        matchesItem in interface ItemType
        Parameters:
        item - The item to be tested
        allowURIPromotion -
        config -
        Returns:
        true if the item is an instance of this type; false otherwise
      • getSuperType

        public ItemType getSuperType​(TypeHierarchy th)
        Get the type from which this item type is derived by restriction. This is the supertype in the XPath type heirarchy, as distinct from the Schema base type: this means that the supertype of xs:boolean is xs:anyAtomicType, whose supertype is item() (rather than xs:anySimpleType).

        In fact the concept of "supertype" is not really well-defined, because the types form a lattice rather than a hierarchy. The only real requirement on this function is that it returns a type that strictly subsumes this type, ideally as narrowly as possible.

        Specified by:
        getSuperType in interface ItemType
        Parameters:
        th - the type hierarchy cache
        Returns:
        the supertype, or null if this type is item()
      • getPrimitiveItemType

        public ItemType getPrimitiveItemType()
        Get the primitive item type corresponding to this item type. For item(), this is Type.ITEM. For node(), it is Type.NODE. For specific node kinds, it is the value representing the node kind, for example Type.ELEMENT. For anyAtomicValue it is Type.ATOMIC_VALUE. For numeric it is Type.NUMBER. For other atomic types it is the primitive type as defined in XML Schema, except that integer, xs:dayTimeDuration, and xs:yearMonthDuration are considered to be primitive types. For function items it is the singular instance FunctionItemType.getInstance().
        Specified by:
        getPrimitiveItemType in interface ItemType
        Returns:
        the corresponding primitive type
      • getPrimitiveType

        public int getPrimitiveType()
        Get the primitive type corresponding to this item type. For item(), this is Type.ITEM. For node(), it is Type.NODE. For specific node kinds, it is the value representing the node kind, for example Type.ELEMENT. For anyAtomicValue it is Type.ATOMIC_VALUE. For numeric it is Type.NUMBER. For other atomic types it is the primitive type as defined in XML Schema, except that INTEGER is considered to be a primitive type.
        Specified by:
        getPrimitiveType in interface ItemType
        Returns:
        the integer fingerprint of the corresponding primitive type
      • toString

        public java.lang.String toString​(NamePool pool)
        Produce a representation of this type name for use in error messages.
        Specified by:
        toString in interface ItemType
        Parameters:
        pool - the name pool
        Returns:
        a string representation of the type, in notation resembling but not necessarily identical to XPath syntax
      • toString

        public java.lang.String toString()
        Produce a representation of this type name for use in error messages.
        Overrides:
        toString in class java.lang.Object
        Returns:
        a string representation of the type, in notation resembling but not necessarily identical to XPath syntax
      • getAtomizedItemType

        public AtomicType getAtomizedItemType()
        Get the item type of the atomic values that will be produced when an item of this type is atomized
        Specified by:
        getAtomizedItemType in interface ItemType
        Returns:
        the item type of the atomic values that will be produced when an item of this type is atomized
      • isAtomizable

        public boolean isAtomizable()
        Ask whether values of this type are atomizable
        Specified by:
        isAtomizable in interface ItemType
        Returns:
        true unless it is known that these items will be elements with element-only content, in which case return false
      • makeFunctionSequenceCoercer

        public Expression makeFunctionSequenceCoercer​(Expression exp,
                                                      RoleLocator role,
                                                      TypeCheckerEnvironment visitor)
                                               throws XPathException
        Create an expression whose effect is to apply function coercion to coerce a function from this type to another type
        Specified by:
        makeFunctionSequenceCoercer in interface FunctionItemType
        Parameters:
        exp - the expression that delivers the supplied sequence of function items (the ones in need of coercion)
        role - information for use in diagnostics
        visitor - the expression visitor, supplies context information
        Returns:
        the coerced function, a function that calls the original function after checking the parameters
        Throws:
        XPathException
      • getDefaultPriority

        public double getDefaultPriority()
        Description copied from interface: ItemType
        Determine the default priority of this item type when used on its own as a Pattern
        Specified by:
        getDefaultPriority in interface ItemType
        Returns:
        the default priority