Package net.sf.saxon.tree.iter

Class ArrayIterator

java.lang.Object
net.sf.saxon.tree.iter.ArrayIterator
All Implemented Interfaces:
Closeable, AutoCloseable, LastPositionFinder, FocusIterator, SequenceIterator, GroundedIterator, LookaheadIterator, ReversibleIterator
Direct Known Subclasses:
ArrayIterator.Of
public abstract class ArrayIterator extends Object implements SequenceIterator, FocusIterator, LastPositionFinder, LookaheadIterator, GroundedIterator, ReversibleIterator
ArrayIterator is used to enumerate items held in a Java array. The items are always held in the correct sorted order for the sequence. The challenge here is getting the generics right, especially in a way that works for C#, which is less tolerant of generic abuse. The solution is to have a non-generic ArrayIterator class, with ArrayIterator.Of<T extends Item> as a subclass. A further subtlety is that we need an ArrayIterator of nodes to implement AxisIterator, so we have another subclass ArrayIterator.OfNodes<N extends NodeInfo> for that purpose.

  • Field Details

    • index

      protected int index

    • start

      protected int start

    • end

      protected int end

  • Constructor Details

    • ArrayIterator

      public ArrayIterator()

  • Method Details

    • makeSliceIterator

      public abstract SequenceIterator 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

    • isActuallyGrounded

      public boolean isActuallyGrounded()
      Description copied from interface: GroundedIterator
      Ask if the iterator is actually grounded. This method must be called before calling GroundedIterator.materialize() or GroundedIterator.getResidue(), because the iterator might be grounded under some conditions and not others (usually when it delegates to another iterator)
      Specified by:
      isActuallyGrounded in interface GroundedIterator
      Returns:
      true if this iterator is grounded

    • supportsHasNext

      public boolean supportsHasNext()
      Description copied from interface: LookaheadIterator
      Ask whether the hasNext() method can be called. This method must be called before calling hasNext(), because some iterators implement this interface, but only support look-ahead under particular circumstances (this is usually because they delegate to another iterator)
      Specified by:
      supportsHasNext in interface LookaheadIterator
      Returns:
      true if the LookaheadIterator.hasNext() method is available

    • position

      public int position()
      Description copied from interface: FocusIterator
      Get the current position. This will usually be zero before the first call on next(), otherwise it will be the number of times that next() has been called. Once next() has returned null, the preferred action is for subsequent calls on position() to return -1, but not all existing implementations follow this practice. (In particular, the EmptyIterator is stateless, and always returns 0 as the value of position(), whether or not next() has been called.)

      This method does not change the state of the iterator.

      Specified by:
      position in interface FocusIterator
      Returns:
      the current position, the position of the item returned by the most recent call of next(). This is 1 after next() has been successfully called once, 2 after it has been called twice, and so on. If next() has never been called, the method returns zero. If the end of the sequence has been reached, the value returned will always be <= 0; the preferred value is -1.

    • getLength

      public int getLength()
      Description copied from interface: FocusIterator
      Get the position of the last item in the sequence
      Specified by:
      getLength in interface FocusIterator
      Specified by:
      getLength in interface LastPositionFinder
      Returns:
      the position of the last item