net.sf.jga.util
Class EmptyIterator<T>

java.lang.Object
  net.sf.jga.util.EmptyIterator<T>

All Implemented Interfaces:

java.lang.Iterable<T>, java.util.Iterator<T>, java.util.ListIterator<T>

public class EmptyIterator<T>
extends java.lang.Object
implements java.util.ListIterator<T>, java.lang.Iterable<T>

Iterator over an empty set of elements.

Author:

David A. Hall

Constructor Summary

EmptyIterator()

Method Summary

void	add(T arg) throws UnsupportedOperationException
boolean	hasNext() Returns false: the set of elements is empty by definition
boolean	hasPrevious() Returns false: the set of elements is empty by definition
java.util.Iterator<T>	iterator()
T	next() throws NoSuchElement exception
int	nextIndex() returns the size of the list (0, in this case)
T	previous() throws NoSuchElement exception
int	previousIndex() returns -1, as there is no previous
void	remove() throws UnsupportedOperationException
void	set(T arg) throws UnsupportedOperationException

Methods inherited from class java.lang.Object

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

Constructor Detail

EmptyIterator

public EmptyIterator()

Method Detail

iterator

public java.util.Iterator<T> iterator()

Specified by:

iterator in interface java.lang.Iterable<T>

hasNext

public boolean hasNext()

Returns false: the set of elements is empty by definition

Specified by:

hasNext in interface java.util.Iterator<T>

Specified by:

hasNext in interface java.util.ListIterator<T>

Returns:

false

next

public T next()

throws NoSuchElement exception

Specified by:

next in interface java.util.Iterator<T>

Specified by:

next in interface java.util.ListIterator<T>

Returns:

nothing

hasPrevious

public boolean hasPrevious()

Returns false: the set of elements is empty by definition

Specified by:

hasPrevious in interface java.util.ListIterator<T>

Returns:

false

previous

public T previous()

throws NoSuchElement exception

Specified by:

previous in interface java.util.ListIterator<T>

Returns:

nothing

nextIndex

public int nextIndex()

returns the size of the list (0, in this case)

Specified by:

nextIndex in interface java.util.ListIterator<T>

Returns:

0

previousIndex

public int previousIndex()

returns -1, as there is no previous

Specified by:

previousIndex in interface java.util.ListIterator<T>

Returns:

-1;

remove

public void remove()

throws UnsupportedOperationException

Specified by:

remove in interface java.util.Iterator<T>

Specified by:

remove in interface java.util.ListIterator<T>

set

public void set(T arg)

throws UnsupportedOperationException

Specified by:

set in interface java.util.ListIterator<T>

add

public void add(T arg)

throws UnsupportedOperationException

Specified by:

add in interface java.util.ListIterator<T>