Package net.sf.saxon.value

Class SingletonNode

    • Constructor Detail

      • SingletonNode

        public SingletonNode​(NodeInfo node)
        Create a node-set containing zero or one nodes
        Parameters:
        node - The node to be contained in the node-set, or null if the node-set is to be empty

    • Method Detail

      • asItem

        public Item asItem()
        Return the value in the form of an Item
        Overrides:
        asItem in class Value
        Returns:
        the value in the form of an Item

      • process

        public void process​(XPathContext context)
             throws XPathException
        Process the instruction, without returning any tail calls
        Overrides:
        process in class Value
        Parameters:
        context - The dynamic context, giving access to the current node, the current variables, etc.
        Throws:
        XPathException

      • getItemType

        public ItemType getItemType​(TypeHierarchy th)
        Determine the data type of the items in the expression. This method determines the most precise type that it can, because it is called when testing that the node conforms to a required type.
        Overrides:
        getItemType in class Value
        Parameters:
        th - the type hierarchy cache
        Returns:
        the most precise possible type of the node.

      • getCardinality

        public int getCardinality()
        Determine the static cardinality
        Overrides:
        getCardinality in class Value
        Returns:
        the cardinality

      • itemAt

        public Item itemAt​(int n)
        Get the n'th item in the sequence (starting from 0). This is defined for all SequenceValues, but its real benefits come for a SequenceValue stored extensionally (or for a MemoClosure, once all the values have been read)
        Specified by:
        itemAt in interface GroundedValue
        Overrides:
        itemAt in class Value
        Parameters:
        n - position of the required item, counting from zero.
        Returns:
        the n'th item in the sequence, where the first item in the sequence is numbered zero. If n is negative or >= the length of the sequence, returns null.

      • subsequence

        public GroundedValue subsequence​(int start,
                                 int length)
        Get a subsequence of the value
        Specified by:
        subsequence in interface GroundedValue
        Parameters:
        start - the index of the first item to be included in the result, counting from zero. A negative value is taken as zero. If the value is beyond the end of the sequence, an empty sequence is returned
        length - the number of items to be included in the result. Specify Integer.MAX_VALUE to get the subsequence up to the end of the base sequence. If the value is negative, an empty sequence is returned. If the value goes off the end of the sequence, the result returns items up to the end of the sequence
        Returns:
        the required subsequence. If min is

      • getNode

        public NodeInfo getNode()
        Get the node that forms the node-set. Return null if there is none.

      • iterate

        public SequenceIterator iterate()
        Return an enumeration of this nodeset value.
        Specified by:
        iterate in class Value
        Returns:
        an iterator over the sequence of items

      • effectiveBooleanValue

        public boolean effectiveBooleanValue()
        Get the effective boolean value
        Overrides:
        effectiveBooleanValue in class Value
        Returns:
        the effective boolean value

      • getStringValue

        public java.lang.String getStringValue()
        Convert the value to a string, using the serialization rules. For atomic values this is the same as a cast; for sequence values it gives a space-separated list. For QNames and NOTATIONS, or lists containing them, it fails.
        Specified by:
        getStringValue in interface ValueRepresentation
        Overrides:
        getStringValue in class Value