java.lang.Object
- org.apache.commons.collections.iterators.ArrayIterator
- - org.apache.commons.collections.iterators.ArrayListIterator

All Implemented Interfaces:

Iterator, ListIterator, ResettableIterator, ResettableListIterator
```
public class ArrayListIterator
extends ArrayIterator
implements ListIterator, ResettableListIterator
```
Implements a ListIterator over an array.
The array can be either an array of object or of primitives. If you know that you have an object array, the ObjectArrayListIterator class is a better choice, as it will perform better.
This iterator does not support add(Object) or ArrayIterator.remove(), as the array cannot be changed in size. The set(Object) method is supported however.

Since:

Commons Collections 3.0

Version:

$Revision: 647116 $ $Date: 2008-04-11 13:23:08 +0200 (Fri, 11 Apr 2008) $

Author:

Neil O'Toole, Stephen Colebourne, Phil Steitz

See Also:

ArrayIterator, Iterator, ListIterator

Field Summary

Fields
Modifier and Type Field Description

protected int lastItemIndex
Holds the index of the last item returned by a call to next() or previous().
- Fields inherited from class org.apache.commons.collections.iterators.ArrayIterator
  array, endIndex, index, startIndex

Constructor Summary

Constructors
Constructor	Description
`ArrayListIterator()`	Constructor for use with `setArray`.
`ArrayListIterator(Object array)`	Constructs an ArrayListIterator that will iterate over the values in the specified array.
`ArrayListIterator(Object array, int startIndex)`	Constructs an ArrayListIterator that will iterate over the values in the specified array from a specific start index.
`ArrayListIterator(Object array, int startIndex, int endIndex)`	Construct an ArrayListIterator that will iterate over a range of values in the specified array.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`add(Object o)`	This iterator does not support modification of its backing collection, and so will always throw an `UnsupportedOperationException` when this method is invoked.
`boolean`	`hasPrevious()`	Returns true if there are previous elements to return from the array.
`Object`	`next()`	Gets the next element from the array.
`int`	`nextIndex()`	Gets the next index to be retrieved.
`Object`	`previous()`	Gets the previous element from the array.
`int`	`previousIndex()`	Gets the index of the item to be retrieved if `previous()` is called.
`void`	`reset()`	Resets the iterator back to the start index.
`void`	`set(Object o)`	Sets the element under the cursor.

Methods inherited from class org.apache.commons.collections.iterators.ArrayIterator
checkBound, getArray, hasNext, remove, setArray

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Iterator
forEachRemaining

Methods inherited from interface java.util.ListIterator
hasNext, remove

- Field Detail
  - lastItemIndex
```
protected int lastItemIndex
```
    Holds the index of the last item returned by a call to next() or previous(). This is set to -1 if neither method has yet been invoked. lastItemIndex is used to to implement the set(java.lang.Object) method.
- Constructor Detail
  - ArrayListIterator
```
public ArrayListIterator()
```
    Constructor for use with setArray.
    Using this constructor, the iterator is equivalent to an empty iterator until ArrayIterator.setArray(Object) is called to establish the array to iterate over.
  - ArrayListIterator
```
public ArrayListIterator(Object array)
```
    Constructs an ArrayListIterator that will iterate over the values in the specified array.
    
    Parameters:
    
    array - the array to iterate over
    
    Throws:
    
    IllegalArgumentException - if array is not an array.
    
    NullPointerException - if array is null
  - ArrayListIterator
```
public ArrayListIterator(Object array,
                         int startIndex)
```
    Constructs an ArrayListIterator that will iterate over the values in the specified array from a specific start index.
    
    Parameters:
    
    array - the array to iterate over
    
    startIndex - the index to start iterating at
    
    Throws:
    
    IllegalArgumentException - if array is not an array.
    
    NullPointerException - if array is null
    
    IndexOutOfBoundsException - if the start index is out of bounds
  - ArrayListIterator
```
public ArrayListIterator(Object array,
                         int startIndex,
                         int endIndex)
```
    Construct an ArrayListIterator that will iterate over a range of values in the specified array.
    
    Parameters:
    
    array - the array to iterate over
    
    startIndex - the index to start iterating at
    
    endIndex - the index (exclusive) to finish iterating at
    
    Throws:
    
    IllegalArgumentException - if array is not an array.
    
    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
  - hasPrevious
```
public boolean hasPrevious()
```
    Returns true if there are previous elements to return from the array.
    
    Specified by:
    
    hasPrevious in interface ListIterator
    
    Returns:
    
    true if there is a previous element to return
  - previous
```
public Object previous()
```
    Gets the previous element from the array.
    
    Specified by:
    
    previous in interface ListIterator
    
    Returns:
    
    the previous element
    
    Throws:
    
    NoSuchElementException - if there is no previous element
  - next
```
public Object next()
```
    Gets the next element from the array.
    
    Specified by:
    
    next in interface Iterator
    
    Specified by:
    
    next in interface ListIterator
    
    Overrides:
    
    next in class ArrayIterator
    
    Returns:
    
    the next element
    
    Throws:
    
    NoSuchElementException - if there is no next element
  - nextIndex
```
public int nextIndex()
```
    Gets the next index to be retrieved.
    
    Specified by:
    
    nextIndex in interface ListIterator
    
    Returns:
    
    the index of the item to be retrieved next
  - previousIndex
```
public int previousIndex()
```
    Gets the index of the item to be retrieved if previous() is called.
    
    Specified by:
    
    previousIndex in interface ListIterator
    
    Returns:
    
    the index of the item to be retrieved next
  - add
```
public void add(Object o)
```
    This iterator does not support modification of its backing collection, and so will always throw an UnsupportedOperationException when this method is invoked.
    
    Specified by:
    
    add in interface ListIterator
    
    Throws:
    
    UnsupportedOperationException - always thrown.
    
    See Also:
    
    ListIterator.set(E)
  - set
```
public void set(Object o)
```
    Sets the element under the cursor.
    This method sets the element that was returned by the last call to next() of previous().
    Note: ListIterator implementations that support add() and remove() only allow set() to be called once per call to next() or previous (see the ListIterator javadoc for more details). Since this implementation does not support add() or remove(), set() may be called as often as desired.
    
    Specified by:
    
    set in interface ListIterator
    
    See Also:
    
    ListIterator.set(E)
  - reset
```
public void reset()
```
    Resets the iterator back to the start index.
    
    Specified by:
    
    reset in interface ResettableIterator
    
    Specified by:
    
    reset in interface ResettableListIterator
    
    Overrides:
    
    reset in class ArrayIterator

Class ArrayListIterator

Field Summary

Fields inherited from class org.apache.commons.collections.iterators.ArrayIterator

Constructor Summary

Method Summary

Methods inherited from class org.apache.commons.collections.iterators.ArrayIterator

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Iterator

Methods inherited from interface java.util.ListIterator

Field Detail

lastItemIndex

Constructor Detail

ArrayListIterator

ArrayListIterator

ArrayListIterator

ArrayListIterator

Method Detail

hasPrevious

previous

next

nextIndex

previousIndex

add

set

reset