structure
Class DoublyLinkedListIterator

java.lang.Object
  |
  +--structure.AbstractIterator
        |
        +--structure.DoublyLinkedListIterator

All Implemented Interfaces:

java.util.Enumeration, java.util.Iterator

public class DoublyLinkedListIterator

extends AbstractIterator

An iterator for traversing the elements of a doubly linked list. The iterator traverses the list beginning at the head, and heads toward tail. Typical use:

      List l = new DoublyLinkedList();
      // ...list gets built up...
      Iterator li = l.iterator();
      while (li.hasNext())
      {
          System.out.println(li.get());
          li.next();
      }
      li.reset();
      while (li.hasNext())
      { .... }
 

Field Summary

protected DoublyLinkedListElement	current Reference to the current node in the list.
protected DoublyLinkedListElement	head Reference to head of the list.
protected DoublyLinkedListElement	tail Sign of the end of the list.

Constructor Summary

DoublyLinkedListIterator(DoublyLinkedListElement h)
Construct an iterator over a doubly linked list hanging from head.

DoublyLinkedListIterator(DoublyLinkedListElement headDummy, DoublyLinkedListElement tailDummy)

Method Summary

java.lang.Object	get() Get reference to value that is current.
boolean	hasNext() Determine if there are more elements to be considered.
java.lang.Object	next() Returns reference to the current element, then increments iterator.
void	reset() Reset the iterator to the head of the list.

Methods inherited from class structure.AbstractIterator

hasMoreElements, nextElement, remove, value

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

head

protected DoublyLinkedListElement head

Reference to head of the list.

tail

protected DoublyLinkedListElement tail

Sign of the end of the list.

current

protected DoublyLinkedListElement current

Reference to the current node in the list.

Constructor Detail

DoublyLinkedListIterator

public DoublyLinkedListIterator(DoublyLinkedListElement h)

Construct an iterator over a doubly linked list hanging from head.

Parameters:

h - The head of the list to be traversed.

DoublyLinkedListIterator

public DoublyLinkedListIterator(DoublyLinkedListElement headDummy,
                                DoublyLinkedListElement tailDummy)

Method Detail

reset

public void reset()

Reset the iterator to the head of the list.

Specified by:

reset in class AbstractIterator

hasNext

public boolean hasNext()

Determine if there are more elements to be considered.

Specified by:

hasNext in interface java.util.Iterator

Specified by:

hasNext in class AbstractIterator

Returns:

True iff there are more elements to be considered.

See Also:

AbstractIterator.hasMoreElements()

next

public java.lang.Object next()

Returns reference to the current element, then increments iterator.

Specified by:

next in interface java.util.Iterator

Specified by:

next in class AbstractIterator

Returns:

Reference to element that was current before increment.

See Also:

AbstractIterator.hasMoreElements(), AbstractIterator.value()

get

public java.lang.Object get()

Get reference to value that is current.

Specified by:

get in class AbstractIterator

Returns:

A reference to the value that is current.