Class LinkedList<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractList<E>

java.util.AbstractSequentialList<E>

java.util.LinkedList<E>

org.datanucleus.store.types.wrappers.LinkedList<E>

All Implemented Interfaces:

Serializable, Cloneable, Iterable<E>, Collection<E>, Deque<E>, List<E>, Queue<E>, SCO<LinkedList<E>>, SCOCollection<LinkedList<E>, E>, SCOContainer<LinkedList<E>>, SCOList<LinkedList<E>, E>

Direct Known Subclasses:

LinkedList

public class LinkedList<E>
extends LinkedList<E>
implements SCOList<LinkedList<E>, E>

A mutable second-class LinkedList object. This is the simplified form that intercepts mutators and marks the field as dirty. It also handles cascade-delete triggering for persistable elements.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected LinkedList<E>	delegate	The internal "delegate".
protected AbstractMemberMetaData	ownerMmd
protected DNStateManager	ownerSM
protected boolean	sorting

Fields inherited from class AbstractList

modCount

Constructor Summary

Constructors

Constructor	Description
LinkedList(DNStateManager sm, AbstractMemberMetaData mmd)	Constructor, using StateManager of the "owner" and the field name.

Method Summary

Modifier and Type	Method	Description
void	add(int index, E element)	Method to add an element to a position in the LinkedList.
boolean	add(E element)	Method to add an element to the LinkedList.
boolean	addAll(int index, Collection<? extends E> elements)	Method to add a Collection to a position in the LinkedList.
boolean	addAll(Collection<? extends E> elements)	Method to add a Collection to the LinkedList.
void	addFirst(E element)	Method to add an element as first in the LinkedList.
void	addLast(E element)	Method to add an element as last in the LinkedList.
void	attachCopy(LinkedList value)	Method to return an attached copy of the passed (detached) value.
void	clear()	Method to clear the LinkedList.
Object	clone()	Clone operator to return a copy of this object.
boolean	contains(Object element)	Method to return if the list contains this element.
boolean	containsAll(Collection c)	Accessor for whether a collection of elements are contained here.
LinkedList	detachCopy(FetchPlanState state)	Method to return a detached copy of the container.
boolean	equals(Object o)
void	forEach(Consumer<? super E> action)
E	get(int index)	Method to retrieve an element no.
String	getFieldName()	Accessor for the field name.
E	getFirst()	Method to retrieve the first element.
E	getLast()	Method to retrieve the last element.
Object	getOwner()	Accessor for the owner object.
LinkedList<E>	getValue()	Accessor for the unwrapped value that we are wrapping.
int	hashCode()
int	indexOf(Object element)	Method to the position of an element.
void	initialise()	Method to initialise the SCO for use, and allowing the SCO to be loaded from the datastore (when we have a backing store).
void	initialise(LinkedList<E> c)	Method to initialise the SCO for use with the provided initial value.
void	initialise(LinkedList<E> newValue, Object oldValue)	Method to initialise the SCO for use, where replacing an old value with a new value such as when calling a setter field passing in a new value.
boolean	isEmpty()	Accessor for whether the LinkedList is empty.
boolean	isLoaded()	Method to return if the SCO has its contents loaded.
Iterator<E>	iterator()	Method to retrieve an iterator for the list.
int	lastIndexOf(Object element)	Method to retrieve the last position of the element.
ListIterator<E>	listIterator(int index)	Method to retrieve a List iterator for the list from the index.
void	load()	Method to effect the load of the data in the SCO.
void	makeDirty()	Utility to mark the object as dirty.
Stream<E>	parallelStream()
E	remove(int index)	Method to remove an element from the LinkedList.
boolean	remove(Object element)	Method to remove (the first occurrence of) an element from the collection
boolean	remove(Object element, boolean allowCascadeDelete)	Method to remove (the first occurrence of) an element from the collection
boolean	removeAll(Collection elements)	Method to remove a Collection from the LinkedList.
E	removeFirst()	Method to remove the first element from the LinkedList.
E	removeLast()	Method to remove the last element from the LinkedList.
boolean	retainAll(Collection c)	Method to retain a Collection of elements (and remove all others).
E	set(int index, E element)	Method to set the element at a position in the LinkedList.
E	set(int index, E element, boolean allowDependentField)	Wrapper addition that allows turning off of the dependent-field checks when doing the position setting.
void	setValue(LinkedList<E> value)	Method to change the delegate value this wraps (to save recreating the wrapper).
int	size()	Accessor for the size of the LinkedList.
void	sort(Comparator<? super E> comp)
Spliterator<E>	spliterator()
Stream<E>	stream()
List<E>	subList(int from, int to)	Accessor for the subList of elements between from and to of the List
Object[]	toArray()
<T> T[]	toArray(T[] a)
void	unsetOwner()	Method to unset the owner and field information.
void	updateEmbeddedElement(E element, int fieldNumber, Object value, boolean makeDirty)	Method to update an embedded element in this collection.
protected Object	writeReplace()	The writeReplace method is called when ObjectOutputStream is preparing to write the object to the stream.

Methods inherited from class LinkedList

descendingIterator, element, offer, offerFirst, offerLast, peek, peekFirst, peekLast, poll, pollFirst, pollLast, pop, push, remove, removeFirstOccurrence, removeLastOccurrence

Methods inherited from class AbstractList

listIterator, removeRange

Methods inherited from class AbstractCollection

toString

Methods inherited from class Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface Collection

removeIf

Methods inherited from interface List

listIterator, replaceAll

Field Details

ownerSM

protected transient DNStateManager ownerSM

ownerMmd

protected transient AbstractMemberMetaData ownerMmd

delegate

protected LinkedList<E> delegate

The internal "delegate".

sorting

protected boolean sorting

Constructor Details

LinkedList

public LinkedList(DNStateManager sm,
 AbstractMemberMetaData mmd)

Constructor, using StateManager of the "owner" and the field name.

Parameters:

sm - The owner StateManager

mmd - Metadata for the member

Method Details

initialise

public void initialise(LinkedList<E> newValue,
 Object oldValue)

Description copied from interface: SCO

Method to initialise the SCO for use, where replacing an old value with a new value such as when calling a setter field passing in a new value. Note that oldValue is marked as Object since for cases where the member type is Collection the newValue could be, for example, ArrayList, and the oldValue of type Collection (representing null).

Specified by:

initialise in interface SCO<E>

Parameters:

newValue - New value (to wrap)

oldValue - Old value (to use in deciding what needs deleting etc)

initialise

public void initialise(LinkedList<E> c)

Description copied from interface: SCO

Method to initialise the SCO for use with the provided initial value. This is used, for example, when retrieving the field from the datastore and setting it in the persistable object.

Specified by:

initialise in interface SCO<E>

Parameters:

c - the object from which to copy the value.

initialise

public void initialise()

Description copied from interface: SCO

Method to initialise the SCO for use, and allowing the SCO to be loaded from the datastore (when we have a backing store). This can be utilised to perform any eager loading of information from the datastore.

Specified by:

initialise in interface SCO<E>

getValue

public LinkedList<E> getValue()

Accessor for the unwrapped value that we are wrapping.

Specified by:

getValue in interface SCO<E>

Returns:

The unwrapped value

setValue

public void setValue(LinkedList<E> value)

Description copied from interface: SCOContainer

Method to change the delegate value this wraps (to save recreating the wrapper).

Specified by:

setValue in interface SCOContainer<E>

Parameters:

value - The new value

load

public void load()

Method to effect the load of the data in the SCO. Used when the SCO supports lazy-loading to tell it to load all now.

Specified by:

load in interface SCOContainer<E>

isLoaded

public boolean isLoaded()

Method to return if the SCO has its contents loaded. Returns true.

Specified by:

isLoaded in interface SCOContainer<E>

Returns:

Whether it is loaded

updateEmbeddedElement

public void updateEmbeddedElement(E element,
 int fieldNumber,
 Object value,
 boolean makeDirty)

Method to update an embedded element in this collection.

Specified by:

updateEmbeddedElement in interface SCOCollection<LinkedList<E>, E>

Parameters:

element - The element

fieldNumber - Number of field in the element

value - New value for this field

makeDirty - Whether to make the SCO field dirty.

getFieldName

public String getFieldName()

Accessor for the field name.

Specified by:

getFieldName in interface SCO<E>

Returns:

The field name

getOwner

public Object getOwner()

Accessor for the owner object.

Specified by:

getOwner in interface SCO<E>

Returns:

The owner object

unsetOwner

public void unsetOwner()

Method to unset the owner and field information.

Specified by:

unsetOwner in interface SCO<E>

makeDirty

public void makeDirty()

Utility to mark the object as dirty.

detachCopy

public LinkedList detachCopy(FetchPlanState state)

Method to return a detached copy of the container. Recurse sthrough the elements so that they are likewise detached.

Specified by:

detachCopy in interface SCO<E>

Parameters:

state - State for detachment process

Returns:

The detached container

attachCopy

public void attachCopy(LinkedList value)

Method to return an attached copy of the passed (detached) value. The returned attached copy is a SCO wrapper. Goes through the existing elements in the store for this owner field and removes ones no longer present, and adds new elements. All elements in the (detached) value are attached.

Specified by:

attachCopy in interface SCO<E>

Parameters:

value - The new (collection) value

clone

public Object clone()

Clone operator to return a copy of this object.

Mutable second-class Objects are required to provide a public clone method in order to allow for copying persistable objects. In contrast to Object.clone(), this method must not throw a CloneNotSupportedException.

Specified by:

clone in interface SCO<E>

Overrides:

clone in class LinkedList<E>

Returns:

The cloned object

contains

public boolean contains(Object element)

Method to return if the list contains this element.

Specified by:

contains in interface Collection<E>

Specified by:

contains in interface Deque<E>

Specified by:

contains in interface List<E>

Overrides:

contains in class LinkedList<E>

Parameters:

element - The element

Returns:

Whether it is contained

containsAll

public boolean containsAll(Collection c)

Accessor for whether a collection of elements are contained here.

Specified by:

containsAll in interface Collection<E>

Specified by:

containsAll in interface List<E>

Overrides:

containsAll in class AbstractCollection<E>

Parameters:

c - The collection of elements.

Returns:

Whether they are contained.

equals

public boolean equals(Object o)

Specified by:

equals in interface Collection<E>

Specified by:

equals in interface List<E>

Overrides:

equals in class AbstractList<E>

get

public E get(int index)

Method to retrieve an element no.

Specified by:

get in interface List<E>

Overrides:

get in class LinkedList<E>

Parameters:

index - The item to retrieve

Returns:

The element at that position.

getFirst

public E getFirst()

Method to retrieve the first element.

Specified by:

getFirst in interface Deque<E>

Overrides:

getFirst in class LinkedList<E>

Returns:

The first element

getLast

public E getLast()

Method to retrieve the last element.

Specified by:

getLast in interface Deque<E>

Overrides:

getLast in class LinkedList<E>

Returns:

The last element

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<E>

Specified by:

hashCode in interface List<E>

Overrides:

hashCode in class AbstractList<E>

indexOf

public int indexOf(Object element)

Method to the position of an element.

Specified by:

indexOf in interface List<E>

Overrides:

indexOf in class LinkedList<E>

Parameters:

element - The element.

Returns:

The position.

isEmpty

public boolean isEmpty()

Accessor for whether the LinkedList is empty.

Specified by:

isEmpty in interface Collection<E>

Specified by:

isEmpty in interface List<E>

Overrides:

isEmpty in class AbstractCollection<E>

Returns:

Whether it is empty.

iterator

public Iterator<E> iterator()

Method to retrieve an iterator for the list.

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Deque<E>

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface List<E>

Overrides:

iterator in class AbstractSequentialList<E>

Returns:

The iterator

listIterator

public ListIterator<E> listIterator(int index)

Method to retrieve a List iterator for the list from the index.

Specified by:

listIterator in interface List<E>

Overrides:

listIterator in class LinkedList<E>

Parameters:

index - The start point

Returns:

The iterator

lastIndexOf

public int lastIndexOf(Object element)

Method to retrieve the last position of the element.

Specified by:

lastIndexOf in interface List<E>

Overrides:

lastIndexOf in class LinkedList<E>

Parameters:

element - The element

Returns:

The last position of this element in the List.

size

public int size()

Accessor for the size of the LinkedList.

Specified by:

size in interface Collection<E>

Specified by:

size in interface Deque<E>

Specified by:

size in interface List<E>

Overrides:

size in class LinkedList<E>

Returns:

The size.

subList

public List<E> subList(int from,
 int to)

Accessor for the subList of elements between from and to of the List

Specified by:

subList in interface List<E>

Overrides:

subList in class AbstractList<E>

Parameters:

from - Start index (inclusive)

to - End index (exclusive)

Returns:

The subList

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface List<E>

Overrides:

toArray in class LinkedList<E>

toArray

public <T> T[] toArray(T[] a)

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface List<E>

Overrides:

toArray in class LinkedList<E>

add

public void add(int index,
 E element)

Method to add an element to a position in the LinkedList.

Specified by:

add in interface List<E>

Overrides:

add in class LinkedList<E>

Parameters:

index - The position

element - The new element

add

public boolean add(E element)

Method to add an element to the LinkedList.

Specified by:

add in interface Collection<E>

Specified by:

add in interface Deque<E>

Specified by:

add in interface List<E>

Specified by:

add in interface Queue<E>

Overrides:

add in class LinkedList<E>

Parameters:

element - The new element

Returns:

Whether it was added ok.

addAll

public boolean addAll(Collection<? extends E> elements)

Method to add a Collection to the LinkedList.

Specified by:

addAll in interface Collection<E>

Specified by:

addAll in interface List<E>

Overrides:

addAll in class LinkedList<E>

Parameters:

elements - The collection

Returns:

Whether it was added ok.

addAll

public boolean addAll(int index,
 Collection<? extends E> elements)

Method to add a Collection to a position in the LinkedList.

Specified by:

addAll in interface List<E>

Overrides:

addAll in class LinkedList<E>

Parameters:

index - Position to insert the collection.

elements - The collection

Returns:

Whether it was added ok.

addFirst

public void addFirst(E element)

Method to add an element as first in the LinkedList.

Specified by:

addFirst in interface Deque<E>

Overrides:

addFirst in class LinkedList<E>

Parameters:

element - The new element

addLast

public void addLast(E element)

Method to add an element as last in the LinkedList.

Specified by:

addLast in interface Deque<E>

Overrides:

addLast in class LinkedList<E>

Parameters:

element - The new element

clear

public void clear()

Method to clear the LinkedList.

Specified by:

clear in interface Collection<E>

Specified by:

clear in interface List<E>

Overrides:

clear in class LinkedList<E>

remove

public E remove(int index)

Method to remove an element from the LinkedList.

Specified by:

remove in interface List<E>

Overrides:

remove in class LinkedList<E>

Parameters:

index - The element position.

Returns:

The object that was removed

remove

public boolean remove(Object element)

Method to remove (the first occurrence of) an element from the collection

Specified by:

remove in interface Collection<E>

Specified by:

remove in interface Deque<E>

Specified by:

remove in interface List<E>

Overrides:

remove in class LinkedList<E>

Parameters:

element - The Element to remove

Returns:

Whether it was removed successfully.

remove

public boolean remove(Object element,
 boolean allowCascadeDelete)

Method to remove (the first occurrence of) an element from the collection

Specified by:

remove in interface SCOCollection<LinkedList<E>, E>

Parameters:

element - The Element to remove

allowCascadeDelete - Whether to cascade delete

Returns:

Whether it was removed successfully.

removeAll

public boolean removeAll(Collection elements)

Method to remove a Collection from the LinkedList.

Specified by:

removeAll in interface Collection<E>

Specified by:

removeAll in interface List<E>

Overrides:

removeAll in class AbstractCollection<E>

Parameters:

elements - The collection

Returns:

Whether it was removed ok.

removeFirst

public E removeFirst()

Method to remove the first element from the LinkedList.

Specified by:

removeFirst in interface Deque<E>

Overrides:

removeFirst in class LinkedList<E>

Returns:

The object that was removed

removeLast

public E removeLast()

Method to remove the last element from the LinkedList.

Specified by:

removeLast in interface Deque<E>

Overrides:

removeLast in class LinkedList<E>

Returns:

The object that was removed

retainAll

public boolean retainAll(Collection c)

Method to retain a Collection of elements (and remove all others).

Specified by:

retainAll in interface Collection<E>

Specified by:

retainAll in interface List<E>

Overrides:

retainAll in class AbstractCollection<E>

Parameters:

c - The collection to retain

Returns:

Whether they were retained successfully.

set

public E set(int index,
 E element,
 boolean allowDependentField)

Wrapper addition that allows turning off of the dependent-field checks when doing the position setting. This means that we can prevent the deletion of the object that was previously in that position. This particular feature is used when attaching a list field and where some elements have changed positions.

Specified by:

set in interface SCOList<LinkedList<E>, E>

Parameters:

index - The position

element - The new element

allowDependentField - Whether to allow dependent-field deletes

Returns:

The element previously at that position

set

public E set(int index,
 E element)

Method to set the element at a position in the LinkedList.

Specified by:

set in interface List<E>

Overrides:

set in class LinkedList<E>

Parameters:

index - The position

element - The new element

Returns:

The element previously at that position

writeReplace

protected Object writeReplace()
                       throws ObjectStreamException

The writeReplace method is called when ObjectOutputStream is preparing to write the object to the stream. The ObjectOutputStream checks whether the class defines the writeReplace method. If the method is defined, the writeReplace method is called to allow the object to designate its replacement in the stream. The object returned should be either of the same type as the object passed in or an object that when read and resolved will result in an object of a type that is compatible with all references to the object.

Returns:

the replaced object

Throws:

ObjectStreamException - if an error occurs

stream

public Stream<E> stream()

Specified by:

stream in interface Collection<E>

parallelStream

public Stream<E> parallelStream()

Specified by:

parallelStream in interface Collection<E>

forEach

public void forEach(Consumer<? super E> action)

Specified by:

forEach in interface Iterable<E>

spliterator

public Spliterator<E> spliterator()

Specified by:

spliterator in interface Collection<E>

Specified by:

spliterator in interface Iterable<E>

Specified by:

spliterator in interface List<E>

Overrides:

spliterator in class LinkedList<E>

sort

public void sort(Comparator<? super E> comp)

Specified by:

sort in interface List<E>