public class TreeList<E> extends AbstractList<E>
List implementation that is optimised for fast insertions and
removals at any index in the list.
This list implementation utilises a tree structure internally to ensure that
all insertions and removals are O(log n). This provides much faster performance
than both an ArrayList and a LinkedList where elements
are inserted and removed repeatedly from anywhere in the list.
The following relative performance statistics are indicative of this class:
get add insert iterate remove
TreeList 3 5 1 2 1
ArrayList 1 1 40 1 40
LinkedList 5800 1 350 2 325
ArrayList is a good general purpose list implementation.
It is faster than TreeList for most operations except inserting
and removing in the middle of the list. ArrayList also uses less
memory as TreeList uses one object per entry.
LinkedList is rarely a good choice of implementation.
TreeList is almost always a good replacement for it, although it
does use slightly more memory.
modCount| Constructor and Description |
|---|
TreeList()
Constructs a new empty list.
|
TreeList(Collection<? extends E> coll)
Constructs a new empty list that copies the specified collection.
|
| Modifier and Type | Method and Description |
|---|---|
void |
add(int index,
E obj)
Adds a new element to the list.
|
boolean |
addAll(Collection<? extends E> c)
Appends all of the elements in the specified collection to the end of this list,
in the order that they are returned by the specified collection's Iterator.
|
void |
clear()
Clears the list, removing all entries.
|
boolean |
contains(Object object)
Searches for the presence of an object in the list.
|
E |
get(int index)
Gets the element at the specified index.
|
int |
indexOf(Object object)
Searches for the index of an object in the list.
|
Iterator<E> |
iterator()
Gets an iterator over the list.
|
ListIterator<E> |
listIterator()
Gets a ListIterator over the list.
|
ListIterator<E> |
listIterator(int fromIndex)
Gets a ListIterator over the list.
|
E |
remove(int index)
Removes the element at the specified index.
|
E |
set(int index,
E obj)
Sets the element at the specified index.
|
int |
size()
Gets the current size of the list.
|
Object[] |
toArray()
Converts the list into an array.
|
add, addAll, equals, hashCode, lastIndexOf, removeRange, subListcontainsAll, isEmpty, remove, removeAll, retainAll, toArray, toStringpublic TreeList()
public TreeList(Collection<? extends E> coll)
coll - the collection to copyNullPointerException - if the collection is nullpublic int size()
size in interface Collection<E>size in interface List<E>size in class AbstractCollection<E>public ListIterator<E> listIterator()
listIterator in interface List<E>listIterator in class AbstractList<E>public ListIterator<E> listIterator(int fromIndex)
listIterator in interface List<E>listIterator in class AbstractList<E>fromIndex - the index to start frompublic boolean contains(Object object)
contains in interface Collection<E>contains in interface List<E>contains in class AbstractCollection<E>object - the object to checkpublic Object[] toArray()
toArray in interface Collection<E>toArray in interface List<E>toArray in class AbstractCollection<E>public boolean addAll(Collection<? extends E> c)
This method runs in O(n + log m) time, where m is
the size of this list and n is the size of c.
addAll in interface Collection<E>addAll in interface List<E>addAll in class AbstractCollection<E>c - the collection to be added to this listtrue if this list changed as a result of the callNullPointerExceptionpublic E set(int index, E obj)
set in interface List<E>set in class AbstractList<E>index - the index to setobj - the object to store at the specified indexIndexOutOfBoundsException - if the index is invalidpublic void clear()
clear in interface Collection<E>clear in interface List<E>clear in class AbstractList<E>Copyright © 2001–2013 The Apache Software Foundation. All rights reserved.