Package net.sf.saxon.tree.iter

Class ArrayIterator<T extends Item>

java.lang.Object
net.sf.saxon.tree.iter.ArrayIterator<T>
All Implemented Interfaces:
LastPositionFinder<T>, SequenceIterator<T>, GroundedIterator<T>, LookaheadIterator<T>, ReversibleIterator<T>, UnfailingIterator<T>
public class ArrayIterator<T extends Item> extends Object implements UnfailingIterator<T>, ReversibleIterator<T>, LastPositionFinder<T>, LookaheadIterator<T>, GroundedIterator<T>
ArrayIterator is used to enumerate items held in an array. The items are always held in the correct sorted order for the sequence.
Author:
Michael H. Kay

  • Field Details

    • items

      protected T extends Item[] items

    • start

      protected int start

    • end

      protected int end

  • Constructor Details

    • ArrayIterator

      public ArrayIterator(T[] nodes)
      Create an iterator over all the items in an array
      Parameters:
      nodes - the array (of any items, not necessarily nodes) to be processed by the iterator

    • ArrayIterator

      public ArrayIterator(T[] items, int start, int end)
      Create an iterator over a range of an array. Note that the start position is zero-based
      Parameters:
      items - the array (of nodes or simple values) to be processed by the iterator
      start - the position of the first item to be processed (numbering from zero). Must be between zero and nodes.length-1; if not, undefined exceptions are likely to occur.
      end - position of first item that is NOT returned, zero-based. Must be beween 1 and nodes.length; if not, undefined exceptions are likely to occur.

  • Method Details

    • makeSliceIterator

      public SequenceIterator<T> makeSliceIterator(int min, int max)
      Create a new ArrayIterator over the same items, with a different start point and end point
      Parameters:
      min - the start position (1-based) of the new ArrayIterator relative to the original
      max - the end position (1-based) of the last item to be delivered by the new ArrayIterator, relative to the original. For example, min=2, max=3 delivers the two items ($base[2], $base[3]). Set this to Integer.MAX_VALUE if there is no end limit.
      Returns:
      an iterator over the items between the min and max positions

    • hasNext

      public boolean hasNext()
      Test whether there are any more items
      Specified by:
      hasNext in interface LookaheadIterator<T extends Item>
      Returns:
      true if there are more items

    • next

      public T next()
      Get the next item in the array
      Specified by:
      next in interface SequenceIterator<T extends Item>
      Specified by:
      next in interface UnfailingIterator<T extends Item>
      Returns:
      the next item in the array

    • current

      public T current()
      Get the current item in the array
      Specified by:
      current in interface SequenceIterator<T extends Item>
      Specified by:
      current in interface UnfailingIterator<T extends Item>
      Returns:
      the item returned by the most recent call of next()

    • position

      public int position()
      Get the position of the current item in the array
      Specified by:
      position in interface SequenceIterator<T extends Item>
      Specified by:
      position in interface UnfailingIterator<T extends Item>
      Returns:
      the current position (starting at 1 for the first item)

    • getLength

      public int getLength()
      Get the number of items in the part of the array being processed
      Specified by:
      getLength in interface LastPositionFinder<T extends Item>
      Returns:
      the number of items; equivalently, the position of the last item

    • close

      public void close()
      Description copied from interface: SequenceIterator
      Close the iterator. This indicates to the supplier of the data that the client does not require any more items to be delivered by the iterator. This may enable the supplier to release resources. After calling close(), no further calls on the iterator should be made; if further calls are made, the effect of such calls is undefined.

      (Currently, closing an iterator is important only when the data is being "pushed" in another thread. Closing the iterator terminates that thread and means that it needs to do no additional work. Indeed, failing to close the iterator may cause the push thread to hang waiting for the buffer to be emptied.)

      Specified by:
      close in interface SequenceIterator<T extends Item>

    • getAnother

      public ArrayIterator<T> getAnother()
      Get another iterator over the same items
      Specified by:
      getAnother in interface SequenceIterator<T extends Item>
      Specified by:
      getAnother in interface UnfailingIterator<T extends Item>
      Returns:
      a new ArrayIterator

    • getReverseIterator

      public SequenceIterator<T> getReverseIterator()
      Get an iterator that processes the same items in reverse order
      Specified by:
      getReverseIterator in interface ReversibleIterator<T extends Item>
      Returns:
      a new ArrayIterator

    • getArray

      public T[] getArray()
      Get the underlying array
      Returns:
      the underlying array being processed by the iterator

    • getStartPosition

      public int getStartPosition()
      Get the initial start position
      Returns:
      the start position of the iterator in the array (zero-based)

    • getEndPosition

      public int getEndPosition()
      Get the end position in the array
      Returns:
      the position in the array (zero-based) of the first item not included in the iteration

    • materialize

      public GroundedValue materialize()
      Return a SequenceValue containing all the items in the sequence returned by this SequenceIterator
      Specified by:
      materialize in interface GroundedIterator<T extends Item>
      Returns:
      the corresponding SequenceValue

    • getProperties

      public int getProperties()
      Get properties of this iterator, as a bit-significant integer.
      Specified by:
      getProperties in interface SequenceIterator<T extends Item>
      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.