public class ListOrderedSet<E> extends AbstractSerializableSetDecorator<E>
Set to ensure that the order of addition is
retained and used by the iterator.
If an object is added to the set for a second time, it will remain in the original position in the iteration. The order can be observed from the set via the iterator or toArray methods.
The ListOrderedSet also has various useful direct methods. These include many
from List, such as get(int),
remove(int) and indexOf(int). An unmodifiable
List view of the set can be obtained via asList().
This class cannot implement the List interface directly as
various interface methods (notably equals/hashCode) are incompatible with a
set.
This class is Serializable from Commons Collections 3.1.
| Modifier | Constructor and Description |
|---|---|
|
ListOrderedSet()
Constructs a new empty
ListOrderedSet using a
HashSet and an ArrayList internally. |
protected |
ListOrderedSet(Set<E> set)
Constructor that wraps (not copies).
|
protected |
ListOrderedSet(Set<E> set,
List<E> list)
Constructor that wraps (not copies) the Set and specifies the list to
use.
|
| Modifier and Type | Method and Description |
|---|---|
boolean |
add(E object) |
void |
add(int index,
E object)
Inserts the specified element at the specified position if it is not yet
contained in this ordered set (optional operation).
|
boolean |
addAll(Collection<? extends E> coll) |
boolean |
addAll(int index,
Collection<? extends E> coll)
Inserts all elements in the specified collection not yet contained in the
ordered set at the specified position (optional operation).
|
List<E> |
asList()
Gets an unmodifiable view of the order of the Set.
|
void |
clear() |
E |
get(int index)
Returns the element at the specified position in this ordered set.
|
int |
indexOf(Object object)
Returns the index of the first occurrence of the specified element in
ordered set.
|
OrderedIterator<E> |
iterator() |
static <E> ListOrderedSet<E> |
listOrderedSet(List<E> list)
Factory method to create an ordered set using the supplied list to retain
order.
|
static <E> ListOrderedSet<E> |
listOrderedSet(Set<E> set)
Factory method to create an ordered set.
|
static <E> ListOrderedSet<E> |
listOrderedSet(Set<E> set,
List<E> list)
Factory method to create an ordered set specifying the list and set to
use.
|
Object |
remove(int index)
Removes the element at the specified position from the ordered set.
|
boolean |
remove(Object object) |
boolean |
removeAll(Collection<?> coll) |
boolean |
retainAll(Collection<?> coll) |
Object[] |
toArray() |
<T> T[] |
toArray(T[] a) |
String |
toString()
Uses the underlying List's toString so that order is achieved.
|
decoratedcontains, containsAll, equals, hashCode, isEmpty, setCollection, sizepublic ListOrderedSet()
ListOrderedSet using a
HashSet and an ArrayList internally.protected ListOrderedSet(Set<E> set)
set - the set to decorate, must not be nullIllegalArgumentException - if set is nullprotected ListOrderedSet(Set<E> set, List<E> list)
The set and list must both be correctly initialised to the same elements.
set - the set to decorate, must not be nulllist - the list to decorate, must not be nullIllegalArgumentException - if set or list is nullpublic static <E> ListOrderedSet<E> listOrderedSet(Set<E> set, List<E> list)
The list and set must both be empty.
E - the element typeset - the set to decorate, must be empty and not nulllist - the list to decorate, must be empty and not nullIllegalArgumentException - if set or list is nullIllegalArgumentException - if either the set or list is not emptypublic static <E> ListOrderedSet<E> listOrderedSet(Set<E> set)
An ArrayList is used to retain order.
E - the element typeset - the set to decorate, must not be nullIllegalArgumentException - if set is nullpublic static <E> ListOrderedSet<E> listOrderedSet(List<E> list)
A HashSet is used for the set behaviour.
NOTE: If the list contains duplicates, the duplicates are removed, altering the specified list.
E - the element typelist - the list to decorate, must not be nullIllegalArgumentException - if list is nullpublic List<E> asList()
public void clear()
clear in interface Collection<E>clear in interface Set<E>clear in class AbstractCollectionDecorator<E>public OrderedIterator<E> iterator()
public boolean add(E object)
add in interface Collection<E>add in interface Set<E>add in class AbstractCollectionDecorator<E>public boolean addAll(Collection<? extends E> coll)
addAll in interface Collection<E>addAll in interface Set<E>addAll in class AbstractCollectionDecorator<E>public boolean remove(Object object)
remove in interface Collection<E>remove in interface Set<E>remove in class AbstractCollectionDecorator<E>public boolean removeAll(Collection<?> coll)
removeAll in interface Collection<E>removeAll in interface Set<E>removeAll in class AbstractCollectionDecorator<E>public boolean retainAll(Collection<?> coll)
retainAll in interface Collection<E>retainAll in interface Set<E>retainAll in class AbstractCollectionDecorator<E>public Object[] toArray()
toArray in interface Collection<E>toArray in interface Set<E>toArray in class AbstractCollectionDecorator<E>public <T> T[] toArray(T[] a)
toArray in interface Collection<E>toArray in interface Set<E>toArray in class AbstractCollectionDecorator<E>public E get(int index)
index - the position of the element in the ordered Set.indexList.get(int)public int indexOf(Object object)
object - the element to search for-1 if
this ordered set does not contain this objectList.indexOf(Object)public void add(int index, E object)
index - the index at which the element is to be insertedobject - the element to be insertedList.add(int, Object)public boolean addAll(int index, Collection<? extends E> coll)
index - the position to insert the elementscoll - the collection containing the elements to be insertedtrue if this ordered set changed as a result of the callList.addAll(int, Collection)public Object remove(int index)
index - the index of the element to be removedList.remove(int)public String toString()
toString in class AbstractCollectionDecorator<E>Copyright © 2001–2013 The Apache Software Foundation. All rights reserved.