Treelist java что это

A 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

LinkedList is rarely a good choice of implementation. TreeList is almost always a good replacement for it, although it does use sligtly more memory.

Since: Commons Collections 3.1 Version: $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $ Author: Joerg Schmuecker, Stephen Colebourne

Field Summary

Fields inherited from class java.util.AbstractList
modCount

Constructor Summary
TreeList () Constructs a new empty list.
TreeList (java.util.Collection coll) Constructs a new empty list that copies the specified list.

Method Summary
void	add (int index, java.lang.Object obj) Adds a new element to the list.
void	clear () Clears the list, removing all entries.
boolean	contains (java.lang.Object object) Searches for the presence of an object in the list.
java.lang.Object	get (int index) Gets the element at the specified index.
int	indexOf (java.lang.Object object) Searches for the index of an object in the list.
java.util.Iterator	iterator () Gets an iterator over the list.
java.util.ListIterator	listIterator () Gets a ListIterator over the list.
java.util.ListIterator	listIterator (int fromIndex) Gets a ListIterator over the list.
java.lang.Object	remove (int index) Removes the element at the specified index.
java.lang.Object	set (int index, java.lang.Object obj) Sets the element at the specified index.
int	size () Gets the current size of the list.
java.lang.Object[]	toArray () Converts the list into an array.

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Methods inherited from class java.util.AbstractList
add, addAll, equals, hashCode, lastIndexOf, removeRange, subList

Methods inherited from class java.util.AbstractCollection
addAll, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toString

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

Methods inherited from interface java.util.List
addAll, containsAll, isEmpty, remove, removeAll, retainAll, toArray

TreeList

public TreeList(java.util.Collection coll)

Parameters: coll — the collection to copy Throws: java.lang.NullPointerException — if the collection is null

Method Detail

get

public java.lang.Object get(int index)

Specified by: get in interface java.util.List Specified by: get in class java.util.AbstractList Parameters: index — the index to retrieve Returns: the element at the specified index

size

Specified by: size in interface java.util.Collection Specified by: size in interface java.util.List Specified by: size in class java.util.AbstractCollection Returns: the current size

iterator

public java.util.Iterator iterator()

Specified by: iterator in interface java.lang.Iterable Specified by: iterator in interface java.util.Collection Specified by: iterator in interface java.util.List Overrides: iterator in class java.util.AbstractList Returns: an iterator over the list

listIterator

public java.util.ListIterator listIterator()

Specified by: listIterator in interface java.util.List Overrides: listIterator in class java.util.AbstractList Returns: the new iterator

listIterator

public java.util.ListIterator listIterator(int fromIndex)

Specified by: listIterator in interface java.util.List Overrides: listIterator in class java.util.AbstractList Parameters: fromIndex — the index to start from Returns: the new iterator

indexOf

public int indexOf(java.lang.Object object)

Specified by: indexOf in interface java.util.List Overrides: indexOf in class java.util.AbstractList Returns: the index of the object, -1 if not found

contains

public boolean contains(java.lang.Object object)

Specified by: contains in interface java.util.Collection Specified by: contains in interface java.util.List Overrides: contains in class java.util.AbstractCollection Returns: true if the object is found

toArray

public java.lang.Object[] toArray()

Specified by: toArray in interface java.util.Collection Specified by: toArray in interface java.util.List Overrides: toArray in class java.util.AbstractCollection Returns: the list as an array

add

public void add(int index, java.lang.Object obj)

Specified by: add in interface java.util.List Overrides: add in class java.util.AbstractList Parameters: index — the index to add before obj — the element to add

set

public java.lang.Object set(int index, java.lang.Object obj)

Specified by: set in interface java.util.List Overrides: set in class java.util.AbstractList Parameters: index — the index to set obj — the object to store at the specified index Returns: the previous object at that index Throws: java.lang.IndexOutOfBoundsException — if the index is invalid

remove

public java.lang.Object remove(int index)

Specified by: remove in interface java.util.List Overrides: remove in class java.util.AbstractList Parameters: index — the index to remove Returns: the previous object at that index

clear

Specified by: clear in interface java.util.Collection Specified by: clear in interface java.util.List Overrides: clear in class java.util.AbstractList

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Treelist java что это

A 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.

Field Summary

Fields inherited from class java.util.AbstractList

Constructor Summary

Method Summary

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.

Methods inherited from class java.util.AbstractList

Methods inherited from class java.util.AbstractCollection

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.List

Constructor Detail

TreeList

Method Detail

get

size

iterator

listIterator

public ListIteratorE> listIterator(int fromIndex)

indexOf

contains

toArray

add

addAll

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. This method runs in O(n + log m) time, where m is the size of this list and n is the size of c .

set

remove

clear

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