Field Detail

• node

  protected NodeInfo node

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

• getLength

  public int getLength​()
                throws XPathException

  Get the length of the sequence

  Overrides:

  getLength in class Value

  Returns:

  the number of items in the sequence

  Throws:

  XPathException

• 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