org.apache.commons.collections4.iterators

Class EnumerationIterator<E>

java.lang.Object

org.apache.commons.collections4.iterators.EnumerationIterator<E>

All Implemented Interfaces:

java.util.Iterator<E>

public class EnumerationIterator<E>
extends java.lang.Object
implements java.util.Iterator<E>

Adapter to make Enumeration instances appear to be Iterator instances.

Since:

1.0

Version:

$Id: EnumerationIterator.java 1477802 2013-04-30 20:01:28Z tn $

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Collection<? super E>	collection The collection to remove elements from
private java.util.Enumeration<? extends E>	enumeration The enumeration being converted
private E	last The last object retrieved

Constructor Summary

Constructors

Constructor and Description
EnumerationIterator() Constructs a new EnumerationIterator that will not function until setEnumeration(Enumeration) is called.
EnumerationIterator(java.util.Enumeration<? extends E> enumeration) Constructs a new EnumerationIterator that provides an iterator view of the given enumeration.
EnumerationIterator(java.util.Enumeration<? extends E> enumeration, java.util.Collection<? super E> collection) Constructs a new EnumerationIterator that will remove elements from the specified collection.

Method Summary

Modifier and Type	Method and Description
java.util.Enumeration<? extends E>	getEnumeration() Returns the underlying enumeration.
boolean	hasNext() Returns true if the underlying enumeration has more elements.
E	next() Returns the next object from the enumeration.
void	remove() Removes the last retrieved element if a collection is attached.
void	setEnumeration(java.util.Enumeration<? extends E> enumeration) Sets the underlying enumeration.

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

Field Detail

collection

private final java.util.Collection<? super E> collection

The collection to remove elements from

enumeration

private java.util.Enumeration<? extends E> enumeration

The enumeration being converted

last

private E last

The last object retrieved

Constructor Detail

EnumerationIterator

public EnumerationIterator()

Constructs a new EnumerationIterator that will not function until setEnumeration(Enumeration) is called.

EnumerationIterator

public EnumerationIterator(java.util.Enumeration<? extends E> enumeration)

Constructs a new EnumerationIterator that provides an iterator view of the given enumeration.

Parameters:

enumeration - the enumeration to use

EnumerationIterator

public EnumerationIterator(java.util.Enumeration<? extends E> enumeration,
                           java.util.Collection<? super E> collection)

Constructs a new EnumerationIterator that will remove elements from the specified collection.

Parameters:

enumeration - the enumeration to use

collection - the collection to remove elements from

Method Detail

hasNext

public boolean hasNext()

Returns true if the underlying enumeration has more elements.

Specified by:

hasNext in interface java.util.Iterator<E>

Returns:

true if the underlying enumeration has more elements

Throws:

java.lang.NullPointerException - if the underlying enumeration is null

next

public E next()

Returns the next object from the enumeration.

Specified by:

next in interface java.util.Iterator<E>

Returns:

the next object from the enumeration

Throws:

java.lang.NullPointerException - if the enumeration is null

remove

public void remove()

Removes the last retrieved element if a collection is attached.

Functions if an associated Collection is known. If so, the first occurrence of the last returned object from this iterator will be removed from the collection.

Specified by:

remove in interface java.util.Iterator<E>

Throws:

java.lang.IllegalStateException - next() not called.

java.lang.UnsupportedOperationException - if no associated collection

getEnumeration

public java.util.Enumeration<? extends E> getEnumeration()

Returns the underlying enumeration.

Returns:

the underlying enumeration

setEnumeration

public void setEnumeration(java.util.Enumeration<? extends E> enumeration)

Sets the underlying enumeration.

Parameters:

enumeration - the new underlying enumeration