public class SetUniqueList<E> extends AbstractSerializableListDecorator<E>
List to ensure that no duplicates are present much
like a Set.
The List interface makes certain assumptions/requirements. This
implementation breaks these in certain ways, but this is merely the result of
rejecting duplicates. Each violation is explained in the method, but it
should not affect you. Bear in mind that Sets require immutable objects to
function correctly.
The ListOrderedSet
class provides an alternative approach, by wrapping an existing Set and
retaining insertion order in the iterator.
This class is Serializable from Commons Collections 3.1.
| Modifier and Type | Method and Description |
|---|---|
boolean |
add(E object)
Adds an element to the list if it is not already present.
|
void |
add(int index,
E object)
Adds an element to a specific index in the list if it is not already
present.
|
boolean |
addAll(java.util.Collection<? extends E> coll)
Adds a collection of objects to the end of the list avoiding duplicates.
|
boolean |
addAll(int index,
java.util.Collection<? extends E> coll)
Adds a collection of objects a specific index in the list avoiding
duplicates.
|
java.util.Set<E> |
asSet()
Gets an unmodifiable view as a Set.
|
void |
clear() |
boolean |
contains(java.lang.Object object) |
boolean |
containsAll(java.util.Collection<?> coll) |
java.util.Iterator<E> |
iterator() |
java.util.ListIterator<E> |
listIterator() |
java.util.ListIterator<E> |
listIterator(int index) |
E |
remove(int index) |
boolean |
remove(java.lang.Object object) |
boolean |
removeAll(java.util.Collection<?> coll) |
boolean |
retainAll(java.util.Collection<?> coll) |
E |
set(int index,
E object)
Sets the value at the specified index avoiding duplicates.
|
static <E> SetUniqueList<E> |
setUniqueList(java.util.List<E> list)
Factory method to create a SetList using the supplied list to retain order.
|
java.util.List<E> |
subList(int fromIndex,
int toIndex) |
equals, get, hashCode, indexOf, lastIndexOfisEmpty, size, toArray, toArray, toStringpublic static <E> SetUniqueList<E> setUniqueList(java.util.List<E> list)
If the list contains duplicates, these are removed (first indexed one
kept). A HashSet is used for the set behaviour.
E - the element typelist - the list to decorate, must not be nullSetUniqueListjava.lang.NullPointerException - if list is nullpublic java.util.Set<E> asSet()
public boolean add(E object)
(Violation) The List interface requires that this
method returns true always. However this class may return
false because of the Set behaviour.
add in interface java.util.Collection<E>add in interface java.util.List<E>add in class AbstractCollectionDecorator<E>object - the object to addpublic void add(int index,
E object)
(Violation) The List interface makes the assumption
that the element is always inserted. This may not happen with this
implementation.
add in interface java.util.List<E>add in class AbstractListDecorator<E>index - the index to insert atobject - the object to addpublic boolean addAll(java.util.Collection<? extends E> coll)
Only elements that are not already in this list will be added, and duplicates from the specified collection will be ignored.
(Violation) The List interface makes the assumption
that the elements are always inserted. This may not happen with this
implementation.
addAll in interface java.util.Collection<E>addAll in interface java.util.List<E>addAll in class AbstractCollectionDecorator<E>coll - the collection to add in iterator orderpublic boolean addAll(int index,
java.util.Collection<? extends E> coll)
Only elements that are not already in this list will be added, and duplicates from the specified collection will be ignored.
(Violation) The List interface makes the assumption
that the elements are always inserted. This may not happen with this
implementation.
addAll in interface java.util.List<E>addAll in class AbstractListDecorator<E>index - the index to insert atcoll - the collection to add in iterator orderpublic E set(int index, E object)
The object is set into the specified index. Afterwards, any previous duplicate is removed. If the object is not already in the list then a normal set occurs. If it is present, then the old version is removed.
set in interface java.util.List<E>set in class AbstractListDecorator<E>index - the index to insert atobject - the object to setpublic boolean remove(java.lang.Object object)
remove in interface java.util.Collection<E>remove in interface java.util.List<E>remove in class AbstractCollectionDecorator<E>public E remove(int index)
remove in interface java.util.List<E>remove in class AbstractListDecorator<E>public boolean removeAll(java.util.Collection<?> coll)
removeAll in interface java.util.Collection<E>removeAll in interface java.util.List<E>removeAll in class AbstractCollectionDecorator<E>public boolean retainAll(java.util.Collection<?> coll)
This implementation iterates over the elements of this list, checking
each element in turn to see if it's contained in coll.
If it's not contained, it's removed from this list. As a consequence,
it is advised to use a collection type for coll that provides
a fast (e.g. O(1)) implementation of Collection.contains(Object).
retainAll in interface java.util.Collection<E>retainAll in interface java.util.List<E>retainAll in class AbstractCollectionDecorator<E>public void clear()
clear in interface java.util.Collection<E>clear in interface java.util.List<E>clear in class AbstractCollectionDecorator<E>public boolean contains(java.lang.Object object)
contains in interface java.util.Collection<E>contains in interface java.util.List<E>contains in class AbstractCollectionDecorator<E>public boolean containsAll(java.util.Collection<?> coll)
containsAll in interface java.util.Collection<E>containsAll in interface java.util.List<E>containsAll in class AbstractCollectionDecorator<E>public java.util.Iterator<E> iterator()
public java.util.ListIterator<E> listIterator()
listIterator in interface java.util.List<E>listIterator in class AbstractListDecorator<E>public java.util.ListIterator<E> listIterator(int index)
listIterator in interface java.util.List<E>listIterator in class AbstractListDecorator<E>public java.util.List<E> subList(int fromIndex, int toIndex)
NOTE: from 4.0, an unmodifiable list will be returned, as changes to the subList can invalidate the parent list.
subList in interface java.util.List<E>subList in class AbstractListDecorator<E>"Copyright © 2010 - 2020 Adobe Systems Incorporated. All Rights Reserved"