com.neeve.lang

Class XShortLinkedList

java.lang.Object

com.neeve.lang.XShortCollectionBase

com.neeve.lang.XShortLinkedList

All Implemented Interfaces:

XShortCollection, XShortList

public class XShortLinkedList
extends XShortCollectionBase
implements XShortList

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.

XShortLinkedList (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 XShortCollectionBase.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 XShortLinkedList.ShortNode 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

Nested Classes

Modifier and Type	Class and Description
static class	XShortLinkedList.ShortNode This class represents a XShortLinkedList node; it allows for direct iteration over the list values.

Constructor Summary

Constructors

Constructor and Description
XShortLinkedList() Creates a list of small initial capacity.
XShortLinkedList(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).
XShortLinkedList(XShortCollection values) Creates a list containing the specified values, in the order they are returned by the collection's iterator.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(int index, short value) Inserts the specified value at the specified position in this list.
boolean	add(short value) Appends the specified value to the end of this list (equivalent to addLast(short)).
boolean	addAll(int index, XShortCollection values) Inserts all of the values in the specified collection into this list at the specified position.
void	addBefore(XShortLinkedList.ShortNode next, short value) Inserts the specified value before the specified Node.
void	addFirst(short value) Inserts the specified value at the beginning of this list.
void	addLast(short 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(short value) Indicates if this collection contains the specified value.
void	delete(XCollection.Record record) Deletes the specified record from this collection.
short	get(int index) Returns the value at the specified position in this list.
short	getFirst() Returns the first value of this list.
short	getLast() Returns the last value of this list.
XShortLinkedList.ShortNode	head() Returns the head record of this collection; it is the record such as head().getNext() holds the first collection value.
int	indexOf(short 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.
XShortIterator	iterator() Returns a simple iterator over the elements in this list
int	lastIndexOf(short 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.
XShortListIterator	listIterator() Returns a list iterator over the elements in this list.
XShortListIterator	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 XShortLinkedList	newInstance() Returns a new list instance.
short	remove(int index) Removes the value at the specified position in this list.
short	removeFirst() Removes and returns the first value of this list.
short	removeLast() Removes and returns the last value of this list (fast).
void	reset()
short	set(int index, short 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.
XShortList	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.
XShortLinkedList.ShortNode	tail() Returns the tail record of this collection; it is the record such as tail().getPrevious() holds the last collection value.
XShortList	unmodifiable() Returns the unmodifiable view associated to this collection.
short	valueOf(XCollection.Record record) Returns the collection value for the specified record.

Methods inherited from class com.neeve.lang.XShortCollectionBase

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

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.neeve.lang.XShortList

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

Methods inherited from interface com.neeve.lang.XShortCollection

reusableIterator, shared, supportsIteratorModifications

Constructor Detail

XShortLinkedList

public XShortLinkedList()

Creates a list of small initial capacity.

XShortLinkedList

public XShortLinkedList(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.

XShortLinkedList

public XShortLinkedList(XShortCollection 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 XShortLinkedList newInstance()

Returns a new list instance.

Returns:

a new, preallocated or recycled list instance.

add

public final boolean add(short value)

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

Specified by:

add in interface XShortCollection

Specified by:

add in interface XShortList

Overrides:

add in class XShortCollectionBase

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 short get(int index)

Returns the value at the specified position in this list.

Specified by:

get in interface XShortList

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 short set(int index,
        short value)

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

Specified by:

set in interface XShortList

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,
       short 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 XShortList

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,
             XShortCollection 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 XShortList

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 short 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 XShortList

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(short 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 XShortList

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(short 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 XShortList

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 XShortIterator iterator()

Returns a simple iterator over the elements in this list

Specified by:

iterator in interface XShortCollection

Specified by:

iterator in interface XShortList

Overrides:

iterator in class XShortCollectionBase

Returns:

an iterator over this list values.

listIterator

public XShortListIterator listIterator()

Returns a list iterator over the elements in this list.

Specified by:

listIterator in interface XShortList

Returns:

an iterator over this list values.

listIterator

public XShortListIterator 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 XShortList

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 XShortList 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 XShortList

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 short getFirst()

Returns the first value of this list.

Returns:

this list's first value.

Throws:

NoSuchElementException - if this list is empty.

getLast

public final short 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(short value)

Inserts the specified value at the beginning of this list.

Parameters:

value - the value to be inserted.

addLast

public void addLast(short value)

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

Parameters:

value - the value to be inserted.

removeFirst

public final short 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 short 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(XShortLinkedList.ShortNode next,
             short 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 XShortLinkedList.ShortNode head()

Description copied from class: XShortCollectionBase

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 XShortCollection

Specified by:

head in class XShortCollectionBase

Returns:

the head record.

tail

public final XShortLinkedList.ShortNode tail()

Description copied from class: XShortCollectionBase

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 XShortCollection

Specified by:

tail in class XShortCollectionBase

Returns:

the tail record.

valueOf

public final short valueOf(XCollection.Record record)

Description copied from class: XShortCollectionBase

Returns the collection value for the specified record.

Specified by:

valueOf in interface XShortCollection

Specified by:

valueOf in class XShortCollectionBase

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: XShortCollectionBase

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 XShortCollection

Specified by:

delete in class XShortCollectionBase

Parameters:

record - the record to be removed.

contains

public final boolean contains(short value)

Description copied from class: XShortCollectionBase

Indicates if this collection contains the specified value.

Specified by:

contains in interface XShortCollection

Specified by:

contains in interface XShortList

Overrides:

contains in class XShortCollectionBase

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: XShortCollectionBase

Returns the number of values in this collection.

Specified by:

size in interface XShortCollection

Specified by:

size in interface XShortList

Specified by:

size in class XShortCollectionBase

Returns:

the number of values.

clear

public final void clear()

Description copied from class: XShortCollectionBase

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

Specified by:

clear in interface XShortCollection

Specified by:

clear in interface XShortList

Overrides:

clear in class XShortCollectionBase

unmodifiable

public XShortList unmodifiable()

Description copied from class: XShortCollectionBase

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 XShortCollection

Overrides:

unmodifiable in class XShortCollectionBase

Returns:

the unmodifiable view over this collection.

reset

public void reset()