Class DistinctValues.DistinctIterator

java.lang.Object
net.sf.saxon.functions.DistinctValues.DistinctIterator
All Implemented Interfaces:
SequenceIterator
Enclosing class:
DistinctValues

public static class DistinctValues.DistinctIterator extends Object implements SequenceIterator
Iterator class to return the distinct values in a sequence
  • Constructor Details

    • DistinctIterator

      public DistinctIterator(SequenceIterator base, AtomicComparer comparer)
      Create an iterator over the distinct values in a sequence
      Parameters:
      base - the input sequence. This must return atomic values only.
      comparer - The comparer used to obtain comparison keys from each value; these comparison keys are themselves compared using equals().
  • Method Details

    • next

      public Item next() throws XPathException
      Get the next item in the sequence.
      Specified by:
      next in interface SequenceIterator
      Returns:
      the next item, or null if there are no more items.
      Throws:
      XPathException - if an error occurs retrieving the next item
    • current

      public Item current()
      Get the current value in the sequence (the one returned by the most recent call on next()). This will be null before the first call of next().
      Specified by:
      current in interface SequenceIterator
      Returns:
      the current item, the one most recently returned by a call on next(); or null, if next() has not been called, or if the end of the sequence has been reached.
    • position

      public int position()
      Get the current position. This will be zero before the first call on next(), otherwise it will be the number of times that next() has been called.
      Specified by:
      position in interface SequenceIterator
      Returns:
      the current position, the position of the item returned by the most recent call of next()
    • getAnother

      public SequenceIterator getAnother() throws XPathException
      Get another SequenceIterator that iterates over the same items as the original, but which is repositioned at the start of the sequence.
      Specified by:
      getAnother in interface SequenceIterator
      Returns:
      a SequenceIterator that iterates over the same items, positioned before the first item
      Throws:
      XPathException - if any error occurs
    • getProperties

      public int getProperties()
      Get properties of this iterator, as a bit-significant integer.
      Specified by:
      getProperties in interface SequenceIterator
      Returns:
      the properties of this iterator. This will be some combination of properties such as SequenceIterator.GROUNDED, SequenceIterator.LAST_POSITION_FINDER, and SequenceIterator.LOOKAHEAD. It is always acceptable to return the value zero, indicating that there are no known special properties. It is acceptable for the properties of the iterator to change depending on its state.