Class Navigator.BaseEnumeration

java.lang.Object
net.sf.saxon.om.AxisIteratorImpl
net.sf.saxon.om.Navigator.BaseEnumeration
All Implemented Interfaces:
AtomizableIterator, AxisIterator, SequenceIterator
Direct Known Subclasses:
Navigator.AncestorEnumeration, Navigator.DescendantEnumeration, Navigator.FollowingEnumeration, Navigator.PrecedingEnumeration
Enclosing class:
Navigator

public abstract static class Navigator.BaseEnumeration extends AxisIteratorImpl
BaseEnumeration is an abstract implementation of an AxisIterator, it simplifies the implementation of the underlying AxisIterator by requiring it to provide only two methods: advance(), and getAnother().

NOTA BENE: BaseEnumeration does not maintain the value of the position variable. It must therefore either (a) be wrapped in an AxisFilter, which does maintain position, or (b) be subclassed by a class that maintains position itself.

  • Constructor Details

    • BaseEnumeration

      public BaseEnumeration()
  • Method Details

    • next

      public final Item next()
      Description copied from interface: AxisIterator
      Get the next item in the sequence.
      Returns:
      the next Item. If there are no more nodes, return null.
    • advance

      public abstract void advance()
      The advance() method must be provided in each concrete implementation. It must leave the variable current set to the next node to be returned in the iteration, or to null if there are no more nodes to be returned.
    • getAnother

      public abstract SequenceIterator getAnother()
      Description copied from interface: AxisIterator
      Get another iterator over the same sequence of items, positioned at the start of the sequence. It must be possible to call this method at any time, whether none, some, or all of the items in the original iterator have been read. The method is non-destructive: it does not change the state of the original iterator.
      Returns:
      a new iterator over the same sequence