Class Queue<E>

java.lang.Object
java.util.AbstractCollection<E>
java.util.AbstractQueue<E>
org.datanucleus.store.types.wrappers.Queue<E>
All Implemented Interfaces:
Serializable, Cloneable, Iterable<E>, Collection<E>, Queue<E>, SCO<Queue<E>>, SCOCollection<Queue<E>,E>, SCOContainer<Queue<E>>
Direct Known Subclasses:
Queue
public class Queue<E> extends AbstractQueue<E> implements SCOCollection<Queue<E>,E>, Cloneable, Serializable
A mutable second-class Queue 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:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected Queue<E>
    delegate
    The internal "delegate".
    protected AbstractMemberMetaData
    ownerMmd
     
    protected DNStateManager
    ownerSM
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    Queue(DNStateManager sm, AbstractMemberMetaData mmd)
    Constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    add(E element)
    Method to add an element to the Collection.
    boolean
    addAll(Collection<? extends E> elements)
    Method to add a collection of elements.
    void
    attachCopy(Queue<E> value)
    Method to return an attached copy of the passed (detached) value.
    void
    clear()
    Method to clear the Collection.
    Object
    clone()
    Creates and returns a copy of this object.
    boolean
    contains(Object element)
    Accessor for whether an element is contained in the Collection.
    boolean
    containsAll(Collection c)
    Accessor for whether a collection of elements are contained here.
    Queue<E>
    detachCopy(FetchPlanState state)
    Method to return a detached copy of the container.
    boolean
    equals(Object o)
    Equality operator.
    void
    forEach(Consumer<? super E> action)
     
    String
    getFieldName()
    Accessor for the field name.
    Object
    getOwner()
    Accessor for the owner object.
    Queue<E>
    getValue()
    Accessor for the unwrapped value that we are wrapping.
    int
    hashCode()
    Hashcode operator.
    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(Queue<E> c)
    Method to initialise the SCO for use with the provided initial value.
    void
    initialise(Queue<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.
    protected void
    initialiseDelegate()
    Convenience method to set up the delegate respecting any comparator specified in MetaData.
    boolean
    isEmpty()
    Accessor for whether the Collection is empty.
    boolean
    isLoaded()
    Method to return if the SCO has its contents loaded.
    Iterator<E>
    iterator()
    Accessor for an iterator for the Collection.
    void
    load()
    Method to effect the load of the data in the SCO.
    void
    makeDirty()
    Utility to mark the object as dirty
    boolean
    offer(E element)
    Method to offer an element to the Queue.
    Stream<E>
    parallelStream()
     
    E
    peek()
    Method to peek at the next element in the Queue.
    E
    poll()
    Method to poll the next element in the Queue.
    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 of elements.
    boolean
    retainAll(Collection<?> c)
    Method to retain a Collection of elements (and remove all others).
    void
    setValue(Queue<E> value)
    Method to change the delegate value this wraps (to save recreating the wrapper).
    int
    size()
    Accessor for the size of the Collection.
    Stream<E>
    stream()
     
    Object[]
    toArray()
    Method to return the Collection as an array.
    <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 AbstractQueue

    element, remove

    Methods inherited from class AbstractCollection

    toString

    Methods inherited from class Object

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

    Methods inherited from interface Collection

    removeIf, spliterator

  • Field Details

  • Constructor Details

  • Method Details

    • initialise

      public void initialise(Queue<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(Queue<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>

    • initialiseDelegate

      protected void initialiseDelegate()
      Convenience method to set up the delegate respecting any comparator specified in MetaData.

    • getValue

      public Queue<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(Queue<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<Queue<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 Queue<E> detachCopy(FetchPlanState state)
      Method to return a detached copy of the container. Recurses through 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(Queue<E> 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()
      Creates and returns 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 Object
      Returns:
      A clone of the object

    • contains

      public boolean contains(Object element)
      Accessor for whether an element is contained in the Collection.
      Specified by:
      contains in interface Collection<E>
      Overrides:
      contains in class AbstractCollection<E>
      Parameters:
      element - The element
      Returns:
      Whether the element is contained here

    • containsAll

      public boolean containsAll(Collection c)
      Accessor for whether a collection of elements are contained here.
      Specified by:
      containsAll in interface Collection<E>
      Overrides:
      containsAll in class AbstractCollection<E>
      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<E>
      Overrides:
      equals in class Object
      Parameters:
      o - The object to compare against.
      Returns:
      Whether this object is the same.

    • hashCode

      public int hashCode()
      Hashcode operator.
      Specified by:
      hashCode in interface Collection<E>
      Overrides:
      hashCode in class Object
      Returns:
      The Hash code.

    • isEmpty

      public boolean isEmpty()
      Accessor for whether the Collection is empty.
      Specified by:
      isEmpty in interface Collection<E>
      Overrides:
      isEmpty in class AbstractCollection<E>
      Returns:
      Whether it is empty.

    • iterator

      public Iterator<E> iterator()
      Accessor for an iterator for the Collection.
      Specified by:
      iterator in interface Collection<E>
      Specified by:
      iterator in interface Iterable<E>
      Specified by:
      iterator in class AbstractCollection<E>
      Returns:
      The iterator

    • peek

      public E peek()
      Method to peek at the next element in the Queue.
      Specified by:
      peek in interface Queue<E>
      Returns:
      The element

    • size

      public int size()
      Accessor for the size of the Collection.
      Specified by:
      size in interface Collection<E>
      Specified by:
      size in class AbstractCollection<E>
      Returns:
      The size

    • toArray

      public Object[] toArray()
      Method to return the Collection as an array.
      Specified by:
      toArray in interface Collection<E>
      Overrides:
      toArray in class AbstractCollection<E>
      Returns:
      The array

    • toArray

      public <T> T[] toArray(T[] a)
      Specified by:
      toArray in interface Collection<E>
      Overrides:
      toArray in class AbstractCollection<E>

    • add

      public boolean add(E element)
      Method to add an element to the Collection.
      Specified by:
      add in interface Collection<E>
      Specified by:
      add in interface Queue<E>
      Overrides:
      add in class AbstractQueue<E>
      Parameters:
      element - The element to add
      Returns:
      Whether it was added successfully.

    • addAll

      public boolean addAll(Collection<? extends E> elements)
      Method to add a collection of elements.
      Specified by:
      addAll in interface Collection<E>
      Overrides:
      addAll in class AbstractQueue<E>
      Parameters:
      elements - The collection of elements to add.
      Returns:
      Whether they were added successfully.

    • clear

      public void clear()
      Method to clear the Collection.
      Specified by:
      clear in interface Collection<E>
      Overrides:
      clear in class AbstractQueue<E>

    • offer

      public boolean offer(E element)
      Method to offer an element to the Queue.
      Specified by:
      offer in interface Queue<E>
      Parameters:
      element - The element to offer
      Returns:
      Whether it was added successfully.

    • poll

      public E poll()
      Method to poll the next element in the Queue.
      Specified by:
      poll in interface Queue<E>
      Returns:
      The element (now 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>
      Overrides:
      remove in class AbstractCollection<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<Queue<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 of elements.
      Specified by:
      removeAll in interface Collection<E>
      Overrides:
      removeAll in class AbstractCollection<E>
      Parameters:
      elements - The collection to remove
      Returns:
      Whether they were removed successfully.

    • retainAll

      public boolean retainAll(Collection<?> c)
      Method to retain a Collection of elements (and remove all others).
      Specified by:
      retainAll in interface Collection<E>
      Overrides:
      retainAll in class AbstractCollection<E>
      Parameters:
      c - The collection to retain
      Returns:
      Whether they were retained successfully.

    • 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

    • forEach

      public void forEach(Consumer<? super E> action)
      Specified by:
      forEach in interface Iterable<E>

    • stream

      public Stream<E> stream()
      Specified by:
      stream in interface Collection<E>

    • parallelStream

      public Stream<E> parallelStream()
      Specified by:
      parallelStream in interface Collection<E>