Class Collection<E>

java.lang.Object
java.util.AbstractCollection<E>
org.datanucleus.store.types.wrappers.Collection<E>
All Implemented Interfaces:
Serializable, Cloneable, Iterable<E>, Collection<E>, SCO<Collection<E>>, SCOCollection<Collection<E>,E>, SCOContainer<Collection<E>>
Direct Known Subclasses:
Collection

public class Collection<E> extends AbstractCollection<E> implements SCOCollection<Collection<E>,E>, Cloneable, Serializable
A mutable second-class Collection 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 Details

  • Constructor Details

    • Collection

      public Collection(DNStateManager sm, AbstractMemberMetaData mmd)
      Constructor. Called from CollectionMapping.
      Parameters:
      sm - StateManager for this collection.
      mmd - Metadata for the member
  • Method Details

    • initialise

      public void initialise(Collection<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(Collection<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 Collection<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(Collection<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<Collection<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 Collection 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(Collection 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
    • 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()
      Specified by:
      toArray in interface Collection<E>
      Overrides:
      toArray in class AbstractCollection<E>
    • 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>
      Overrides:
      add in class AbstractCollection<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 AbstractCollection<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 AbstractCollection<E>
    • 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<Collection<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>
    • spliterator

      public Spliterator spliterator()
      Specified by:
      spliterator in interface Collection<E>
      Specified by:
      spliterator in interface Iterable<E>