org.apache.commons.collections.iterators
Class ObjectArrayIterator<E>

java.lang.Object
  org.apache.commons.collections.iterators.ObjectArrayIterator<E>

All Implemented Interfaces:

Iterator<E>, ResettableIterator<E>

Direct Known Subclasses:

ObjectArrayListIterator

public class ObjectArrayIterator<E>
extends Object
implements Iterator<E>, ResettableIterator<E>

An Iterator over an array of objects.

This iterator does not support remove(), as the object array cannot be structurally modified.

The iterator implements a reset() method, allowing the reset of the iterator back to the start if required.

Since:

Commons Collections 3.0

Version:

$Revision: 1.1.1.1 $ $Date: 2005/05/23 04:34:57 $

Author:

James Strachan, Mauricio S. Moura, Michael A. Smith, Neil O'Toole, Stephen Colebourne, Matt Hall, John Watkinson, Phil Steitz

Field Summary

protected E[]	array The array
protected int	endIndex The end index to loop to
protected int	index The current iterator index
protected int	startIndex The start index to loop from

Constructor Summary

ObjectArrayIterator()
Constructor for use with setArray.

ObjectArrayIterator(E[] array)
Constructs an ObjectArrayIterator that will iterate over the values in the specified array.

ObjectArrayIterator(E[] array, int start)
Constructs an ObjectArrayIterator that will iterate over the values in the specified array from a specific start index.

ObjectArrayIterator(E[] array, int start, int end)
Construct an ObjectArrayIterator that will iterate over a range of values in the specified array.

Method Summary

E[]	getArray() Gets the array that this iterator is iterating over.
int	getEndIndex() Gets the end index to loop to.
int	getStartIndex() Gets the start index to loop from.
boolean	hasNext() Returns true if there are more elements to return from the array.
E	next() Returns the next element in the array.
void	remove() Throws UnsupportedOperationException.
void	reset() Resets the iterator back to the start index.
void	setArray(E[] array) Sets the array that the ArrayIterator should iterate over.

Methods inherited from class java.lang.Object

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

Field Detail

array

protected E[] array

The array

startIndex

protected int startIndex

The start index to loop from

endIndex

protected int endIndex

The end index to loop to

index

protected int index

The current iterator index

Constructor Detail

ObjectArrayIterator

public ObjectArrayIterator()

Constructor for use with setArray.

Using this constructor, the iterator is equivalent to an empty iterator until setArray(E[]) is called to establish the array to iterate over.

ObjectArrayIterator

public ObjectArrayIterator(E[] array)

Constructs an ObjectArrayIterator that will iterate over the values in the specified array.

Parameters:

array - the array to iterate over

Throws:

NullPointerException - if array is null

ObjectArrayIterator

public ObjectArrayIterator(E[] array,
                           int start)

Constructs an ObjectArrayIterator that will iterate over the values in the specified array from a specific start index.

Parameters:

array - the array to iterate over

start - the index to start iterating at

Throws:

NullPointerException - if array is null

IndexOutOfBoundsException - if the start index is out of bounds

ObjectArrayIterator

public ObjectArrayIterator(E[] array,
                           int start,
                           int end)

Construct an ObjectArrayIterator that will iterate over a range of values in the specified array.

Parameters:

array - the array to iterate over

start - the index to start iterating at

end - the index (exclusive) to finish iterating at

Throws:

IndexOutOfBoundsException - if the start or end index is out of bounds

IllegalArgumentException - if end index is before the start

NullPointerException - if array is null

Method Detail

hasNext

public boolean hasNext()

Returns true if there are more elements to return from the array.

Specified by:

hasNext in interface Iterator<E>

Returns:

true if there is a next element to return

next

public E next()

Returns the next element in the array.

Specified by:

next in interface Iterator<E>

Returns:

the next element in the array

Throws:

NoSuchElementException - if all the elements in the array have already been returned

remove

public void remove()

Throws UnsupportedOperationException.

Specified by:

remove in interface Iterator<E>

Throws:

UnsupportedOperationException - always

getArray

public E[] getArray()

Gets the array that this iterator is iterating over.

Returns:

the array this iterator iterates over, or null if the no-arg constructor was used and setArray(E[]) has never been called with a valid array.

setArray

public void setArray(E[] array)

Sets the array that the ArrayIterator should iterate over.

This method may only be called once, otherwise an IllegalStateException will occur.

The reset() method can be used to reset the iterator if required.

Parameters:

array - the array that the iterator should iterate over

Throws:

IllegalStateException - if the array was set in the constructor

NullPointerException - if array is null

getStartIndex

public int getStartIndex()

Gets the start index to loop from.

Returns:

the start index

getEndIndex

public int getEndIndex()

Gets the end index to loop to.

Returns:

the end index

reset

public void reset()

Resets the iterator back to the start index.

Specified by:

reset in interface ResettableIterator<E>