structure
Class CircularListIterator

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

All Implemented Interfaces:

Enumeration, Iterator

class CircularListIterator

extends AbstractIterator

An iterator for traversing the elements of a circular list. The iterator traverses the list beginning at the head, and heads toward tail.

Typical use:

      List l = new CircularList();
      // ...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 SinglyLinkedListElement	current The current value of the iterator.
protected SinglyLinkedListElement	tail The tail of the traversed list.

Constructor Summary

CircularListIterator(SinglyLinkedListElement t)
Constructs an iterator over circular list whose tail is t

Method Summary

Object	get() Determine the current value of iterator.
boolean	hasNext() Determine if there are unconsidered elements.
Object	next() Return the current value and increment iterator.
void	reset() Resets iterator to consider 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, registerNatives, toString, wait, wait, wait

Field Detail

tail

protected SinglyLinkedListElement tail

The tail of the traversed list.

current

protected SinglyLinkedListElement current

The current value of the iterator.

Constructor Detail

CircularListIterator

public CircularListIterator(SinglyLinkedListElement t)

Constructs an iterator over circular list whose tail is t

Parameters:

t - The tail of the list to be traversed.

Method Detail

reset

public void reset()

Resets iterator to consider the head of the list.

Overrides:

reset in class AbstractIterator

Postcondition:

rests iterator to point to head of list

hasNext

public boolean hasNext()

Determine if there are unconsidered elements.

Overrides:

hasNext in class AbstractIterator

Postcondition:

returns true if some elements not visited

Returns:

True iff some element has not been considered.

next

public Object next()

Return the current value and increment iterator.

Overrides:

next in class AbstractIterator

Precondition:

hasNext()

Postcondition:

returns current element, increments iterator

Returns:

The current value before incrementing.

get

public Object get()

Determine the current value of iterator.

Overrides:

get in class AbstractIterator

Precondition:

hasNext()

Postcondition:

returns current value

Returns:

The current value of the iterator.