org.datanucleus.store.types.wrappers.LinkedList Maven / Gradle / Ivy
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/**********************************************************************
Copyright (c) 2007 Andy Jefferson and others. All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
Contributors:
...
**********************************************************************/
package org.datanucleus.store.types.wrappers;
import java.io.ObjectStreamException;
import java.util.Collection;
import java.util.Iterator;
import java.util.ListIterator;
import org.datanucleus.flush.CollectionAddOperation;
import org.datanucleus.flush.CollectionRemoveOperation;
import org.datanucleus.flush.ListAddAtOperation;
import org.datanucleus.flush.ListRemoveAtOperation;
import org.datanucleus.metadata.AbstractMemberMetaData;
import org.datanucleus.state.FetchPlanState;
import org.datanucleus.state.ObjectProvider;
import org.datanucleus.state.RelationshipManager;
import org.datanucleus.store.types.SCOList;
import org.datanucleus.store.types.SCOListIterator;
import org.datanucleus.store.types.SCOUtils;
import org.datanucleus.util.Localiser;
import org.datanucleus.util.NucleusLogger;
/**
* 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.
*/
public class LinkedList extends java.util.LinkedList implements SCOList
{
protected transient ObjectProvider ownerOP;
protected transient AbstractMemberMetaData ownerMmd;
/** The internal "delegate". */
protected java.util.LinkedList delegate;
/**
* Constructor, using the ObjectProvider of the "owner" and the field name.
* @param ownerOP The owner ObjectProvider
* @param mmd Metadata for the member
*/
public LinkedList(ObjectProvider ownerOP, AbstractMemberMetaData mmd)
{
this.ownerOP = ownerOP;
this.ownerMmd = mmd;
}
public void initialise(java.util.LinkedList newValue, Object oldValue)
{
initialise(newValue);
}
public void initialise(java.util.LinkedList c)
{
if (c != null)
{
delegate = c;
}
else
{
delegate = new java.util.LinkedList();
}
if (NucleusLogger.PERSISTENCE.isDebugEnabled())
{
NucleusLogger.PERSISTENCE.debug(Localiser.msg("023003", this.getClass().getName(), ownerOP.getObjectAsPrintable(), ownerMmd.getName(), "" + size(),
SCOUtils.getSCOWrapperOptionsMessage(true, false, true, false)));
}
}
public void initialise()
{
initialise(null);
}
// ----------------------- Implementation of SCO methods -------------------
/**
* Accessor for the unwrapped value that we are wrapping.
* @return The unwrapped value
*/
public java.util.LinkedList getValue()
{
return delegate;
}
/**
* 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.
*/
public void load()
{
// Always loaded
}
/**
* Method to return if the SCO has its contents loaded. Returns true.
* @return Whether it is loaded
*/
public boolean isLoaded()
{
return true;
}
/**
* Method to update an embedded element in this collection.
* @param element The element
* @param fieldNumber Number of field in the element
* @param value New value for this field
* @param makeDirty Whether to make the SCO field dirty.
*/
public void updateEmbeddedElement(Object element, int fieldNumber, Object value, boolean makeDirty)
{
if (makeDirty)
{
// Just mark field in embedded owners as dirty
makeDirty();
}
}
/**
* Accessor for the field name.
* @return The field name
**/
public String getFieldName()
{
return ownerMmd.getName();
}
/**
* Accessor for the owner object.
* @return The owner object
**/
public Object getOwner()
{
return (ownerOP != null ? ownerOP.getObject() : null);
}
/**
* Method to unset the owner and field information.
**/
public synchronized void unsetOwner()
{
if (ownerOP != null)
{
ownerOP = null;
ownerMmd = null;
}
}
/**
* Utility to mark the object as dirty.
**/
public void makeDirty()
{
if (ownerOP != null)
{
ownerOP.makeDirty(ownerMmd.getAbsoluteFieldNumber());
}
}
/**
* Method to return a detached copy of the container.
* Recurse sthrough the elements so that they are likewise detached.
* @param state State for detachment process
* @return The detached container
*/
public java.util.LinkedList detachCopy(FetchPlanState state)
{
java.util.LinkedList detached = new java.util.LinkedList();
SCOUtils.detachCopyForCollection(ownerOP, toArray(), state, detached);
return detached;
}
/**
* 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.
* @param value The new (collection) value
*/
public void attachCopy(java.util.LinkedList value)
{
// Attach all of the elements in the new list
boolean elementsWithoutIdentity = SCOUtils.collectionHasElementsWithoutIdentity(ownerMmd);
java.util.List attachedElements = new java.util.ArrayList(value.size());
SCOUtils.attachCopyForCollection(ownerOP, value.toArray(), attachedElements, elementsWithoutIdentity);
// Update the attached list with the detached elements
SCOUtils.updateListWithListElements(this, attachedElements);
}
// ------------------- Implementation of LinkedList methods ----------------
/**
* 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.
* @return The cloned object
*/
public Object clone()
{
return delegate.clone();
}
/**
* Method to return if the list contains this element.
* @param element The element
* @return Whether it is contained
**/
public boolean contains(Object element)
{
return delegate.contains(element);
}
/**
* Accessor for whether a collection of elements are contained here.
* @param c The collection of elements.
* @return Whether they are contained.
**/
public synchronized boolean containsAll(java.util.Collection c)
{
return delegate.containsAll(c);
}
/**
* Equality operator.
* @param o The object to compare against.
* @return Whether this object is the same.
**/
public synchronized boolean equals(Object o)
{
return delegate.equals(o);
}
/**
* Method to retrieve an element no.
* @param index The item to retrieve
* @return The element at that position.
**/
public Object get(int index)
{
return delegate.get(index);
}
/**
* Method to retrieve the first element.
* @return The first element
**/
public Object getFirst()
{
return delegate.getFirst();
}
/**
* Method to retrieve the last element.
* @return The last element
**/
public Object getLast()
{
return delegate.getLast();
}
/**
* Hashcode operator.
* @return The Hash code.
**/
public synchronized int hashCode()
{
return delegate.hashCode();
}
/**
* Method to the position of an element.
* @param element The element.
* @return The position.
**/
public int indexOf(Object element)
{
return delegate.indexOf(element);
}
/**
* Accessor for whether the LinkedList is empty.
* @return Whether it is empty.
**/
public boolean isEmpty()
{
return delegate.isEmpty();
}
/**
* Method to retrieve an iterator for the list.
* @return The iterator
**/
public Iterator iterator()
{
return new SCOListIterator(this, ownerOP, delegate, null, true, -1);
}
/**
* Method to retrieve a List iterator for the list from the index.
* @param index The start point
* @return The iterator
**/
public ListIterator listIterator(int index)
{
return new SCOListIterator(this, ownerOP, delegate, null, true, index);
}
/**
* Method to retrieve the last position of the element.
* @param element The element
* @return The last position of this element in the List.
**/
public int lastIndexOf(Object element)
{
return delegate.lastIndexOf(element);
}
/**
* Accessor for the size of the LinkedList.
* @return The size.
**/
public int size()
{
return delegate.size();
}
/**
* Accessor for the subList of elements between from and to of the List
* @param from Start index (inclusive)
* @param to End index (exclusive)
* @return The subList
**/
public synchronized java.util.List subList(int from,int to)
{
return delegate.subList(from,to);
}
/**
* Method to return the list as an array.
* @return The array
**/
public synchronized Object[] toArray()
{
return delegate.toArray();
}
/**
* Method to return the list as an array.
* @param a The runtime types of the array being defined by this param
* @return The array
**/
public synchronized Object[] toArray(Object a[])
{
return delegate.toArray(a);
}
/**
* Method to add an element to a position in the LinkedList.
* @param index The position
* @param element The new element
**/
public void add(int index, Object element)
{
delegate.add(index, element);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
ownerOP.getExecutionContext().getRelationshipManager(ownerOP).relationAdd(ownerMmd.getAbsoluteFieldNumber(), element);
}
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new ListAddAtOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), index, element));
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
/**
* Method to add an element to the LinkedList.
* @param element The new element
* @return Whether it was added ok.
**/
public boolean add(Object element)
{
boolean success = delegate.add(element);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
ownerOP.getExecutionContext().getRelationshipManager(ownerOP).relationAdd(ownerMmd.getAbsoluteFieldNumber(), element);
}
if (success)
{
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionAddOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), element));
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* Method to add a Collection to the LinkedList.
* @param elements The collection
* @return Whether it was added ok.
**/
public boolean addAll(Collection elements)
{
boolean success = delegate.addAll(elements);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
// Relationship management
Iterator iter = elements.iterator();
RelationshipManager relMgr = ownerOP.getExecutionContext().getRelationshipManager(ownerOP);
while (iter.hasNext())
{
relMgr.relationAdd(ownerMmd.getAbsoluteFieldNumber(), iter.next());
}
}
if (success)
{
if (SCOUtils.useQueuedUpdate(ownerOP))
{
for (Object element : elements)
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionAddOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), element));
}
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* Method to add a Collection to a position in the LinkedList.
* @param index Position to insert the collection.
* @param elements The collection
* @return Whether it was added ok.
**/
public boolean addAll(int index, Collection elements)
{
boolean success = delegate.addAll(index, elements);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
// Relationship management
Iterator iter = elements.iterator();
RelationshipManager relMgr = ownerOP.getExecutionContext().getRelationshipManager(ownerOP);
while (iter.hasNext())
{
relMgr.relationAdd(ownerMmd.getAbsoluteFieldNumber(), iter.next());
}
}
if (success)
{
if (SCOUtils.useQueuedUpdate(ownerOP))
{
int pos = index;
for (Object element : elements)
{
ownerOP.getExecutionContext().addOperationToQueue(new ListAddAtOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), pos++, element));
}
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* Method to add an element as first in the LinkedList.
* @param element The new element
**/
public void addFirst(Object element)
{
delegate.addFirst(element);
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
/**
* Method to add an element as last in the LinkedList.
* @param element The new element
**/
public void addLast(Object element)
{
delegate.addLast(element);
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionAddOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), element));
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
/**
* Method to clear the LinkedList.
*/
public synchronized void clear()
{
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
// Relationship management
Iterator iter = delegate.iterator();
RelationshipManager relMgr = ownerOP.getExecutionContext().getRelationshipManager(ownerOP);
while (iter.hasNext())
{
relMgr.relationRemove(ownerMmd.getAbsoluteFieldNumber(), iter.next());
}
}
if (ownerOP != null && !delegate.isEmpty())
{
// Cascade delete
if (SCOUtils.useQueuedUpdate(ownerOP))
{
java.util.List copy = new java.util.ArrayList(delegate);
Iterator iter = copy.iterator();
while (iter.hasNext())
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionRemoveOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), iter.next(), true));
}
}
else if (SCOUtils.hasDependentElement(ownerMmd))
{
java.util.List copy = new java.util.ArrayList(delegate);
Iterator iter = copy.iterator();
while (iter.hasNext())
{
ownerOP.getExecutionContext().deleteObjectInternal(iter.next());
}
}
}
delegate.clear();
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
/**
* Method to remove an element from the LinkedList.
* @param index The element position.
* @return The object that was removed
**/
public Object remove(int index)
{
Object element = delegate.remove(index);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
ownerOP.getExecutionContext().getRelationshipManager(ownerOP).relationRemove(ownerMmd.getAbsoluteFieldNumber(), element);
}
if (ownerOP != null && SCOUtils.hasDependentElement(ownerMmd))
{
// Cascade delete
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new ListRemoveAtOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), index, element));
}
else if (SCOUtils.hasDependentElement(ownerMmd))
{
ownerOP.getExecutionContext().deleteObjectInternal(element);
}
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
return element;
}
/**
* Method to remove an element from the List
* @param element The Element to remove
* @return Whether it was removed successfully.
**/
public synchronized boolean remove(Object element)
{
return remove(element, true);
}
/**
* Method to remove an element from the List
* @param element The Element to remove
* @return Whether it was removed successfully.
**/
public synchronized boolean remove(Object element, boolean allowCascadeDelete)
{
boolean success = delegate.remove(element);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
ownerOP.getExecutionContext().getRelationshipManager(ownerOP).relationRemove(ownerMmd.getAbsoluteFieldNumber(), element);
}
if (ownerOP != null && allowCascadeDelete &&
SCOUtils.hasDependentElement(ownerMmd))
{
// Cascade delete
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionRemoveOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), element, allowCascadeDelete));
}
else if (SCOUtils.hasDependentElement(ownerMmd))
{
ownerOP.getExecutionContext().deleteObjectInternal(element);
}
}
if (success)
{
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* Method to remove a Collection from the LinkedList.
* @param elements The collection
* @return Whether it was removed ok.
**/
public boolean removeAll(Collection elements)
{
boolean success = delegate.removeAll(elements);
if (ownerOP != null && ownerOP.getExecutionContext().getManageRelations())
{
// Relationship management
Iterator iter = elements.iterator();
RelationshipManager relMgr = ownerOP.getExecutionContext().getRelationshipManager(ownerOP);
while (iter.hasNext())
{
relMgr.relationRemove(ownerMmd.getAbsoluteFieldNumber(), iter.next());
}
}
if (ownerOP != null && elements != null && !elements.isEmpty())
{
// Cascade delete
if (SCOUtils.useQueuedUpdate(ownerOP))
{
Iterator iter = elements.iterator();
while (iter.hasNext())
{
ownerOP.getExecutionContext().addOperationToQueue(new CollectionRemoveOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), iter.next(), true));
}
}
else if (SCOUtils.hasDependentElement(ownerMmd))
{
Iterator iter = elements.iterator();
while (iter.hasNext())
{
ownerOP.getExecutionContext().deleteObjectInternal(iter.next());
}
}
}
if (success)
{
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* Method to remove the first element from the LinkedList.
* @return The object that was removed
**/
public Object removeFirst()
{
return remove(0);
}
/**
* Method to remove the last element from the LinkedList.
* @return The object that was removed
*/
public Object removeLast()
{
return remove(size()-1);
}
/**
* Method to retain a Collection of elements (and remove all others).
* @param c The collection to retain
* @return Whether they were retained successfully.
**/
public synchronized boolean retainAll(java.util.Collection c)
{
boolean success = delegate.retainAll(c);
if (success)
{
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
}
return success;
}
/**
* 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.
* @param index The position
* @param element The new element
* @return The element previously at that position
*/
public Object set(int index, Object element, boolean allowDependentField)
{
Object prevElement = delegate.set(index, element);
if (ownerOP != null && allowDependentField && !delegate.contains(prevElement))
{
// Cascade delete
if (SCOUtils.useQueuedUpdate(ownerOP))
{
ownerOP.getExecutionContext().addOperationToQueue(new ListRemoveAtOperation(ownerOP, ownerMmd.getAbsoluteFieldNumber(), index, prevElement));
}
else if (SCOUtils.hasDependentElement(ownerMmd))
{
ownerOP.getExecutionContext().deleteObjectInternal(prevElement);
}
}
makeDirty();
if (ownerOP != null && !ownerOP.getExecutionContext().getTransaction().isActive())
{
ownerOP.getExecutionContext().processNontransactionalUpdate();
}
return prevElement;
}
/**
* Method to set the element at a position in the LinkedList.
* @param index The position
* @param element The new element
* @return The element previously at that position
**/
public Object set(int index, Object element)
{
return set(index, element, true);
}
/**
* 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.
* @return the replaced object
* @throws ObjectStreamException if an error occurs
*/
protected Object writeReplace() throws ObjectStreamException
{
return new java.util.LinkedList(delegate);
}
}