org.datanucleus.store.types.wrappers

Class LinkedList

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractList<E>

java.util.AbstractSequentialList<E>

java.util.LinkedList

org.datanucleus.store.types.wrappers.LinkedList

All Implemented Interfaces:

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

Direct Known Subclasses:

LinkedList

public class LinkedList
extends LinkedList
implements SCOList<LinkedList>

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 and Description
protected LinkedList	delegate The internal "delegate".
protected AbstractMemberMetaData	ownerMmd
protected ObjectProvider	ownerOP

Fields inherited from class java.util.AbstractList

modCount

Constructor Summary

Constructors

Constructor and Description
LinkedList(ObjectProvider ownerOP, AbstractMemberMetaData mmd) Constructor, using the ObjectProvider of the "owner" and the field name.

Method Summary

Modifier and Type	Method and Description
void	add(int index, Object element) Method to add an element to a position in the LinkedList.
boolean	add(Object element) Method to add an element to the LinkedList.
boolean	addAll(Collection elements) Method to add a Collection to the LinkedList.
boolean	addAll(int index, Collection elements) Method to add a Collection to a position in the LinkedList.
void	addFirst(Object element) Method to add an element as first in the LinkedList.
void	addLast(Object 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) Equality operator.
Object	get(int index) Method to retrieve an element no.
String	getFieldName() Accessor for the field name.
Object	getFirst() Method to retrieve the first element.
Object	getLast() Method to retrieve the last element.
Object	getOwner() Accessor for the owner object.
LinkedList	getValue() Accessor for the unwrapped value that we are wrapping.
int	hashCode() Hashcode operator.
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 c) Method to initialise the SCO for use with the provided initial value.
void	initialise(LinkedList 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	iterator() Method to retrieve an iterator for the list.
int	lastIndexOf(Object element) Method to retrieve the last position of the element.
ListIterator	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.
Object	remove(int index) Method to remove an element from the LinkedList.
boolean	remove(Object element) Method to remove an element from the List
boolean	remove(Object element, boolean allowCascadeDelete) Method to remove an element from the List
boolean	removeAll(Collection elements) Method to remove a Collection from the LinkedList.
Object	removeFirst() Method to remove the first element from the LinkedList.
Object	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).
Object	set(int index, Object element) Method to set the element at a position in the LinkedList.
Object	set(int index, Object element, boolean allowDependentField) Wrapper addition that allows turning off of the dependent-field checks when doing the position setting.
void	setValue(LinkedList value) Method to change the delegate value this wraps (to save recreating the wrapper).
int	size() Accessor for the size of the LinkedList.
List	subList(int from, int to) Accessor for the subList of elements between from and to of the List
Object[]	toArray() Method to return the list as an array.
Object[]	toArray(Object[] a) Method to return the list as an array.
void	unsetOwner() Method to unset the owner and field information.
void	updateEmbeddedElement(Object 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 java.util.LinkedList

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

Methods inherited from class java.util.AbstractList

listIterator, removeRange

Methods inherited from class java.util.AbstractCollection

toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.List

listIterator, replaceAll, sort

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable

forEach

Field Detail

ownerOP

protected transient ObjectProvider ownerOP

ownerMmd

protected transient AbstractMemberMetaData ownerMmd

delegate

protected LinkedList delegate

The internal "delegate".

Constructor Detail

LinkedList

public LinkedList(ObjectProvider ownerOP,
                  AbstractMemberMetaData mmd)

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

Parameters:

ownerOP - The owner ObjectProvider

mmd - Metadata for the member

Method Detail

initialise

public void initialise(LinkedList 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<LinkedList>

Parameters:

newValue - New value (to wrap)

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

initialise

public void initialise(LinkedList 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<LinkedList>

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<LinkedList>

getValue

public LinkedList getValue()

Accessor for the unwrapped value that we are wrapping.

Specified by:

getValue in interface SCO<LinkedList>

Returns:

The unwrapped value

setValue

public void setValue(LinkedList 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<LinkedList>

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<LinkedList>

isLoaded

public boolean isLoaded()

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

Specified by:

isLoaded in interface SCOContainer<LinkedList>

Returns:

Whether it is loaded

updateEmbeddedElement

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

Method to update an embedded element in this collection.

Specified by:

updateEmbeddedElement in interface SCOCollection<LinkedList>

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<LinkedList>

Returns:

The field name

getOwner

public Object getOwner()

Accessor for the owner object.

Specified by:

getOwner in interface SCO<LinkedList>

Returns:

The owner object

unsetOwner

public void unsetOwner()

Method to unset the owner and field information.

Specified by:

unsetOwner in interface SCO<LinkedList>

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<LinkedList>

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<LinkedList>

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<LinkedList>

Overrides:

clone in class LinkedList

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

Specified by:

contains in interface Deque

Specified by:

contains in interface List

Overrides:

contains in class LinkedList

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

Specified by:

containsAll in interface List

Overrides:

containsAll in class AbstractCollection

Parameters:

c - The collection of elements.

Returns:

Whether they are contained.

equals

public boolean equals(Object o)

Equality operator.

Specified by:

equals in interface Collection

Specified by:

equals in interface List

Overrides:

equals in class AbstractList

Parameters:

o - The object to compare against.

Returns:

Whether this object is the same.

get

public Object get(int index)

Method to retrieve an element no.

Specified by:

get in interface List

Overrides:

get in class LinkedList

Parameters:

index - The item to retrieve

Returns:

The element at that position.

getFirst

public Object getFirst()

Method to retrieve the first element.

Specified by:

getFirst in interface Deque

Overrides:

getFirst in class LinkedList

Returns:

The first element

getLast

public Object getLast()

Method to retrieve the last element.

Specified by:

getLast in interface Deque

Overrides:

getLast in class LinkedList

Returns:

The last element

hashCode

public int hashCode()

Hashcode operator.

Specified by:

hashCode in interface Collection

Specified by:

hashCode in interface List

Overrides:

hashCode in class AbstractList

Returns:

The Hash code.

indexOf

public int indexOf(Object element)

Method to the position of an element.

Specified by:

indexOf in interface List

Overrides:

indexOf in class LinkedList

Parameters:

element - The element.

Returns:

The position.

isEmpty

public boolean isEmpty()

Accessor for whether the LinkedList is empty.

Specified by:

isEmpty in interface Collection

Specified by:

isEmpty in interface List

Overrides:

isEmpty in class AbstractCollection

Returns:

Whether it is empty.

iterator

public Iterator iterator()

Method to retrieve an iterator for the list.

Specified by:

iterator in interface Iterable

Specified by:

iterator in interface Collection

Specified by:

iterator in interface Deque

Specified by:

iterator in interface List

Overrides:

iterator in class AbstractSequentialList

Returns:

The iterator

listIterator

public ListIterator listIterator(int index)

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

Specified by:

listIterator in interface List

Overrides:

listIterator in class LinkedList

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

Overrides:

lastIndexOf in class LinkedList

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

Specified by:

size in interface Deque

Specified by:

size in interface List

Overrides:

size in class LinkedList

Returns:

The size.

subList

public List subList(int from,
                    int to)

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

Specified by:

subList in interface List

Overrides:

subList in class AbstractList

Parameters:

from - Start index (inclusive)

to - End index (exclusive)

Returns:

The subList

toArray

public Object[] toArray()

Method to return the list as an array.

Specified by:

toArray in interface Collection

Specified by:

toArray in interface List

Overrides:

toArray in class LinkedList

Returns:

The array

toArray

public Object[] toArray(Object[] a)

Method to return the list as an array.

Specified by:

toArray in interface Collection

Specified by:

toArray in interface List

Overrides:

toArray in class LinkedList

Parameters:

a - The runtime types of the array being defined by this param

Returns:

The array

add

public void add(int index,
                Object element)

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

Specified by:

add in interface List

Overrides:

add in class LinkedList

Parameters:

index - The position

element - The new element

add

public boolean add(Object element)

Method to add an element to the LinkedList.

Specified by:

add in interface Collection

Specified by:

add in interface Deque

Specified by:

add in interface List

Specified by:

add in interface Queue

Overrides:

add in class LinkedList

Parameters:

element - The new element

Returns:

Whether it was added ok.

addAll

public boolean addAll(Collection elements)

Method to add a Collection to the LinkedList.

Specified by:

addAll in interface Collection

Specified by:

addAll in interface List

Overrides:

addAll in class LinkedList

Parameters:

elements - The collection

Returns:

Whether it was added ok.

addAll

public boolean addAll(int index,
                      Collection elements)

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

Specified by:

addAll in interface List

Overrides:

addAll in class LinkedList

Parameters:

index - Position to insert the collection.

elements - The collection

Returns:

Whether it was added ok.

addFirst

public void addFirst(Object element)

Method to add an element as first in the LinkedList.

Specified by:

addFirst in interface Deque

Overrides:

addFirst in class LinkedList

Parameters:

element - The new element

addLast

public void addLast(Object element)

Method to add an element as last in the LinkedList.

Specified by:

addLast in interface Deque

Overrides:

addLast in class LinkedList

Parameters:

element - The new element

clear

public void clear()

Method to clear the LinkedList.

Specified by:

clear in interface Collection

Specified by:

clear in interface List

Overrides:

clear in class LinkedList

remove

public Object remove(int index)

Method to remove an element from the LinkedList.

Specified by:

remove in interface List

Overrides:

remove in class LinkedList

Parameters:

index - The element position.

Returns:

The object that was removed

remove

public boolean remove(Object element)

Method to remove an element from the List

Specified by:

remove in interface Collection

Specified by:

remove in interface Deque

Specified by:

remove in interface List

Overrides:

remove in class LinkedList

Parameters:

element - The Element to remove

Returns:

Whether it was removed successfully.

remove

public boolean remove(Object element,
                      boolean allowCascadeDelete)

Method to remove an element from the List

Specified by:

remove in interface SCOCollection<LinkedList>

Parameters:

element - The Element to remove

allowCascadeDelete - Whether to allow 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

Specified by:

removeAll in interface List

Overrides:

removeAll in class AbstractCollection

Parameters:

elements - The collection

Returns:

Whether it was removed ok.

removeFirst

public Object removeFirst()

Method to remove the first element from the LinkedList.

Specified by:

removeFirst in interface Deque

Overrides:

removeFirst in class LinkedList

Returns:

The object that was removed

removeLast

public Object removeLast()

Method to remove the last element from the LinkedList.

Specified by:

removeLast in interface Deque

Overrides:

removeLast in class LinkedList

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

Specified by:

retainAll in interface List

Overrides:

retainAll in class AbstractCollection

Parameters:

c - The collection to retain

Returns:

Whether they were retained successfully.

set

public Object set(int index,
                  Object 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>

Parameters:

index - The position

element - The new element

allowDependentField - Whether to allow dependent-field deletes

Returns:

The element previously at that position

set

public Object set(int index,
                  Object element)

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

Specified by:

set in interface List

Overrides:

set in class LinkedList

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