com.neeve.lang
Class XLongLinkedList

java.lang.Object
  com.neeve.lang.XLongCollectionBase
      com.neeve.lang.XLongLinkedList

All Implemented Interfaces:

XLongCollection, XLongList

public class XLongLinkedList
extends XLongCollectionBase
implements XLongList

This class represents a linked list with real-time behavior; smooth capacity increase and no memory allocation as long as the list size does not exceed its initial capacity.

All of the operations perform as could be expected for a doubly-linked list (insertion/deletion at the end of the list are nonetheless the fastest). Operations that index into the list will traverse the list from the begining or the end whichever is closer to the specified index. Random access operations can be significantly accelerated by splitting the list into smaller ones.

XLongLinkedList (as for any XCollection sub-class) supports fast iterations without using iterators.[code] XLinkedList list = new XLinkedList(); for (XLinkedList.Node n = list.head(), end = list.tail(); (n = n.getNext()) != end;) { String value = n.getValue(); // No typecast necessary. }[/code]

Alternatively The list can be iterated over using XLongCollectionBase.reusableIterator(). Utilization of these iterators does not introduce garbage because they are created once. However, these iterators may not be used concurrently by multiple threads as they are single instance by nature.

Custom list implementations may override the newNode() method in order to return their own XLongLinkedList.LongNode implementation (with additional fields for example).

This class was based on collections code from http://javolution.org, but modified for use outside of realtime jvms.

Nested Class Summary

static class

XLongLinkedList.LongNode This class represents a XLongLinkedList node; it allows for direct iteration over the list values.

Constructor Summary

XLongLinkedList()
Creates a list of small initial capacity.

XLongLinkedList(int capacity)
Creates a list of specified initial capacity; unless the list size reaches the specified capacity, operations on this list will not allocate memory (no lazy object creation).

XLongLinkedList(XLongCollection values)
Creates a list containing the specified values, in the order they are returned by the collection's iterator.

Method Summary

void	add(int index, long value) Inserts the specified value at the specified position in this list.
boolean	add(long value) Appends the specified value to the end of this list (equivalent to addLast(long)).
boolean	addAll(int index, XLongCollection values) Inserts all of the values in the specified collection into this list at the specified position.
void	addBefore(XLongLinkedList.LongNode next, long value) Inserts the specified value before the specified Node.
void	addFirst(long value) Inserts the specified value at the beginning of this list.
void	addLast(long value) Appends the specified value to the end of this list (fast).
void	clear() Removes all of the values from this collection (optional operation).
boolean	contains(long value) Indicates if this collection contains the specified value.
void	delete(XCollection.Record record) Deletes the specified record from this collection.
long	get(int index) Returns the value at the specified position in this list.
long	getFirst() Returns the first value of this list.
long	getLast() Returns the last value of this list.
XLongLinkedList.LongNode	head() Returns the head record of this collection; it is the record such as head().getNext() holds the first collection value.
int	indexOf(long value) Returns the index in this list of the first occurrence of the specified value, or -1 if this list does not contain this value.
XLongIterator	iterator() Returns a simple iterator over the elements in this list
int	lastIndexOf(long value) Returns the index in this list of the last occurrence of the specified value, or -1 if this list does not contain this value.
XLongListIterator	listIterator() Returns a list iterator over the elements in this list.
XLongListIterator	listIterator(int index) Returns a list iterator from the specified position The specified index indicates the first value that would be returned by an initial call to the next method.
static XLongLinkedList	newInstance() Returns a new list instance.
long	remove(int index) Removes the value at the specified position in this list.
long	removeFirst() Removes and returns the first value of this list.
long	removeLast() Removes and returns the last value of this list (fast).
void	reset()
long	set(int index, long value) Replaces the value at the specified position in this list with the specified value.
int	size() Returns the number of values in this collection.
XLongList	subList(int fromIndex, int toIndex) Returns a view of the portion of this list between the specified indexes If the specified indexes are equal, the returned list is empty.
XLongLinkedList.LongNode	tail() Returns the tail record of this collection; it is the record such as tail().getPrevious() holds the last collection value.
XLongList	unmodifiable() Returns the unmodifiable view associated to this collection.
long	valueOf(XCollection.Record record) Returns the collection value for the specified record.

Methods inherited from class com.neeve.lang.XLongCollectionBase

addAll, containsAll, equals, hashCode, isEmpty, remove, removeAll, retainAll, reusableIterator, shared, toArray, toArray, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.neeve.lang.XLongList

addAll, containsAll, equals, hashCode, isEmpty, remove, removeAll, retainAll, toArray, toArray

Methods inherited from interface com.neeve.lang.XLongCollection

reusableIterator, shared

Constructor Detail

XLongLinkedList

public XLongLinkedList()

Creates a list of small initial capacity.

XLongLinkedList

public XLongLinkedList(int capacity)

Creates a list of specified initial capacity; unless the list size reaches the specified capacity, operations on this list will not allocate memory (no lazy object creation).

Parameters:

capacity - the initial capacity.

XLongLinkedList

public XLongLinkedList(XLongCollection values)

Creates a list containing the specified values, in the order they are returned by the collection's iterator.

Parameters:

values - the values to be placed into this list.

Method Detail

newInstance

public static XLongLinkedList newInstance()

Returns a new list instance.

Returns:

a new, preallocated or recycled list instance.

add

public final boolean add(long value)

Appends the specified value to the end of this list (equivalent to addLast(long)).

Specified by:

add in interface XLongCollection

Specified by:

add in interface XLongList

Overrides:

add in class XLongCollectionBase

Parameters:

value - the value to be appended to this list.

Returns:

true (as per the general contract of the Collection.add method).

get

public final long get(int index)

Returns the value at the specified position in this list.

Specified by:

get in interface XLongList

Parameters:

index - the index of value to return.

Returns:

the value at the specified position in this list.

Throws:

IndexOutOfBoundsException - if (index < 0) || (index >= size())

set

public final long set(int index,
                      long value)

Replaces the value at the specified position in this list with the specified value.

Specified by:

set in interface XLongList

Parameters:

index - the index of value to replace.

value - the value to be stored at the specified position.

Returns:

the value previously at the specified position.

Throws:

IndexOutOfBoundsException - if (index < 0) || (index >= size())

add

public final void add(int index,
                      long value)

Inserts the specified value at the specified position in this list. Shifts the value currently at that position (if any) and any subsequent values to the right (adds one to their indices).

Specified by:

add in interface XLongList

Parameters:

index - the index at which the specified value is to be inserted.

value - the value to be inserted.

Throws:

IndexOutOfBoundsException - if (index < 0) || (index > size())

addAll

public final boolean addAll(int index,
                            XLongCollection values)

Inserts all of the values in the specified collection into this list at the specified position. Shifts the value currently at that position (if any) and any subsequent values to the right (increases their indices).

Specified by:

addAll in interface XLongList

Parameters:

index - the index at which to insert first value from the specified collection.

values - the values to be inserted into this list.

Returns:

true if this list changed as a result of the call; false otherwise.

Throws:

IndexOutOfBoundsException - if (index < 0) || (index > size())

remove

public final long remove(int index)

Removes the value at the specified position in this list. Shifts any subsequent values to the left (subtracts one from their indices). Returns the value that was removed from the list.

Specified by:

remove in interface XLongList

Parameters:

index - the index of the value to removed.

Returns:

the value previously at the specified position.

Throws:

IndexOutOfBoundsException - if (index < 0) || (index >= size())

indexOf

public final int indexOf(long value)

Returns the index in this list of the first occurrence of the specified value, or -1 if this list does not contain this value.

Specified by:

indexOf in interface XLongList

Parameters:

value - the value to search for.

Returns:

the index in this list of the first occurrence of the specified value, or -1 if this list does not contain this value.

lastIndexOf

public final int lastIndexOf(long value)

Returns the index in this list of the last occurrence of the specified value, or -1 if this list does not contain this value.

Specified by:

lastIndexOf in interface XLongList

Parameters:

value - the value to search for.

Returns:

the index in this list of the last occurrence of the specified value, or -1 if this list does not contain this value.

iterator

public XLongIterator iterator()

Returns a simple iterator over the elements in this list

Specified by:

iterator in interface XLongCollection

Specified by:

iterator in interface XLongList

Overrides:

iterator in class XLongCollectionBase

Returns:

an iterator over this list values.

listIterator

public XLongListIterator listIterator()

Returns a list iterator over the elements in this list.

Specified by:

listIterator in interface XLongList

Returns:

an iterator over this list values.

listIterator

public XLongListIterator listIterator(int index)

Returns a list iterator from the specified position The specified index indicates the first value that would be returned by an initial call to the next method. An initial call to the previous method would return the value with the specified index minus one.

Specified by:

listIterator in interface XLongList

Parameters:

index - index of first value to be returned from the list iterator (by a call to the next method).

Returns:

a list iterator over the values in this list starting at the specified position in this list.

Throws:

IndexOutOfBoundsException - if the index is out of range [code](index < 0 || index > size())[/code].

subList

public final XLongList subList(int fromIndex,
                               int toIndex)

Returns a view of the portion of this list between the specified indexes If the specified indexes are equal, the returned list is empty. The returned list is backed by this list, so non-structural changes in the returned list are reflected in this list, and vice-versa. This method eliminates the need for explicit range operations (of the sort that commonly exist for arrays). Any operation that expects a list can be used as a range operation by passing a subList view instead of a whole list. For example, the following idiom removes a range of values from a list: list.subList(from, to).clear(); Similar idioms may be constructed for indexOf and lastIndexOf, and all of the algorithms in the Collections class can be applied to a subList. The semantics of the list returned by this method become undefined if the backing list (i.e., this list) is structurally modified in any way other than via the returned list (structural modifications are those that change the size of this list, or otherwise perturb it in such a fashion that iterations in progress may yield incorrect results).

Specified by:

subList in interface XLongList

Parameters:

fromIndex - low endpoint (inclusive) of the subList.

toIndex - high endpoint (exclusive) of the subList.

Returns:

a view of the specified range within this list.

Throws:

IndexOutOfBoundsException - if [code](fromIndex < 0 || toIndex > size || fromIndex < toIndex)[/code]

getFirst

public final long getFirst()

Returns the first value of this list.

Returns:

this list's first value.

Throws:

NoSuchElementException - if this list is empty.

getLast

public final long getLast()

Returns the last value of this list.

Returns:

this list's last value.

Throws:

NoSuchElementException - if this list is empty.

addFirst

public final void addFirst(long value)

Inserts the specified value at the beginning of this list.

Parameters:

value - the value to be inserted.

addLast

public void addLast(long value)

Appends the specified value to the end of this list (fast).

Parameters:

value - the value to be inserted.

removeFirst

public final long removeFirst()

Removes and returns the first value of this list.

Returns:

this list's first value before this call.

Throws:

NoSuchElementException - if this list is empty.

removeLast

public final long removeLast()

Removes and returns the last value of this list (fast).

Returns:

this list's last value before this call.

Throws:

NoSuchElementException - if this list is empty.

addBefore

public final void addBefore(XLongLinkedList.LongNode next,
                            long value)

Inserts the specified value before the specified Node.

Parameters:

next - the Node before which this value is inserted.

value - the value to be inserted.

head

public final XLongLinkedList.LongNode head()

Description copied from class: XLongCollectionBase

Returns the head record of this collection; it is the record such as head().getNext() holds the first collection value.

Specified by:

head in interface XLongCollection

Specified by:

head in class XLongCollectionBase

Returns:

the head record.

tail

public final XLongLinkedList.LongNode tail()

Description copied from class: XLongCollectionBase

Returns the tail record of this collection; it is the record such as tail().getPrevious() holds the last collection value.

Specified by:

tail in interface XLongCollection

Specified by:

tail in class XLongCollectionBase

Returns:

the tail record.

valueOf

public final long valueOf(XCollection.Record record)

Description copied from class: XLongCollectionBase

Returns the collection value for the specified record.

Specified by:

valueOf in interface XLongCollection

Specified by:

valueOf in class XLongCollectionBase

Parameters:

record - the record whose current value is returned.

Returns:

the current value.

delete

public final void delete(XCollection.Record record)

Description copied from class: XLongCollectionBase

Deletes the specified record from this collection.

Implementation must ensure that removing a record from the collection does not affect in any way the records preceding the record being removed (it might affect the next records though, e.g. in a list collection, the indices of the subsequent records will change).

Specified by:

delete in interface XLongCollection

Specified by:

delete in class XLongCollectionBase

Parameters:

record - the record to be removed.

contains

public final boolean contains(long value)

Description copied from class: XLongCollectionBase

Indicates if this collection contains the specified value.

Specified by:

contains in interface XLongCollection

Specified by:

contains in interface XLongList

Overrides:

contains in class XLongCollectionBase

Parameters:

value - the value whose presence in this collection is to be tested.

Returns:

true if this collection contains the specified value;false otherwise.

size

public final int size()

Description copied from class: XLongCollectionBase

Returns the number of values in this collection.

Specified by:

size in interface XLongCollection

Specified by:

size in interface XLongList

Specified by:

size in class XLongCollectionBase

Returns:

the number of values.

clear

public final void clear()

Description copied from class: XLongCollectionBase

Removes all of the values from this collection (optional operation).

Specified by:

clear in interface XLongCollection

Specified by:

clear in interface XLongList

Overrides:

clear in class XLongCollectionBase

unmodifiable

public XLongList unmodifiable()

Description copied from class: XLongCollectionBase

Returns the unmodifiable view associated to this collection. Attempts to modify the returned collection result in an UnsupportedOperationException being thrown.

Specified by:

unmodifiable in interface XLongCollection

Overrides:

unmodifiable in class XLongCollectionBase

Returns:

the unmodifiable view over this collection.

reset

public void reset()