Package org.datanucleus.store.types.wrappers

Class HashSet<E>

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable, java.lang.Iterable<E>, java.util.Collection<E>, java.util.Set<E>, SCO<java.util.HashSet<E>>, SCOCollection<java.util.HashSet<E>,​E>, SCOContainer<java.util.HashSet<E>>
    Direct Known Subclasses:
    HashSet
    public class HashSet<E>
extends java.util.HashSet<E>
implements SCOCollection<java.util.HashSet<E>,​E>
    A mutable second-class HashSet 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

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean add​(E element)
      Method to add an element to the set.
      boolean addAll​(java.util.Collection<? extends E> elements)
      Method to add a collection to the set.
      void attachCopy​(java.util.HashSet value)
      Method to return an attached copy of the passed (detached) value.
      void clear()
      Method to clear the HashSet
      java.lang.Object clone()
      Creates and returns a copy of this object.
      boolean contains​(java.lang.Object element)
      Accessor for whether an element is contained in this set.
      boolean containsAll​(java.util.Collection c)
      Accessor for whether a collection is contained in this set.
      java.util.HashSet detachCopy​(FetchPlanState state)
      Method to return a detached copy of the container.
      boolean equals​(java.lang.Object o)  
      void forEach​(java.util.function.Consumer<? super E> action)  
      java.lang.String getFieldName()
      Accessor for the field name.
      java.lang.Object getOwner()
      Accessor for the owner object.
      java.util.HashSet<E> getValue()
      Accessor for the unwrapped value that we are wrapping.
      int hashCode()  
      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​(java.util.HashSet<E> c)
      Method to initialise the SCO for use with the provided initial value.
      void initialise​(java.util.HashSet<E> newValue, java.lang.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 HashSet is empty.
      boolean isLoaded()
      Method to return if the SCO has its contents loaded.
      java.util.Iterator<E> iterator()
      Accessor for an iterator for the Set.
      void load()
      Method to effect the load of the data in the SCO.
      void makeDirty()
      Utility to mark the object as dirty
      java.util.stream.Stream<E> parallelStream()  
      boolean remove​(java.lang.Object element)
      Method to remove (the first occurrence of) an element from the collection
      boolean remove​(java.lang.Object element, boolean allowCascadeDelete)
      Method to remove (the first occurrence of) an element from the collection
      boolean removeAll​(java.util.Collection elements)
      Method to remove all elements from the collection from the set.
      boolean retainAll​(java.util.Collection c)
      Method to retain a Collection of elements (and remove all others).
      void setValue​(java.util.HashSet<E> value)
      Method to change the delegate value this wraps (to save recreating the wrapper).
      int size()
      Accessor for the size of the HashSet.
      java.util.Spliterator spliterator()  
      java.util.stream.Stream<E> stream()  
      java.lang.Object[] toArray()  
      <T> T[] toArray​(T[] a)  
      void unsetOwner()
      Method to unset the owner and field information.
      void updateEmbeddedElement​(E element, int fieldNumber, java.lang.Object value, boolean makeDirty)
      Method to update an embedded element in this collection.
      protected java.lang.Object writeReplace()
      The writeReplace method is called when ObjectOutputStream is preparing to write the object to the stream.

      • 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.Collection

        removeIf

    • Constructor Detail

      • HashSet

        public HashSet​(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 Detail

      • initialise

        public void initialise​(java.util.HashSet<E> newValue,
                       java.lang.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​(java.util.HashSet<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 java.util.HashSet<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​(java.util.HashSet<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,
                                  java.lang.Object value,
                                  boolean makeDirty)
        Method to update an embedded element in this collection.
        Specified by:
        updateEmbeddedElement in interface SCOCollection<java.util.HashSet<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 java.lang.String getFieldName()
        Accessor for the field name.
        Specified by:
        getFieldName in interface SCO<E>
        Returns:
        The field name

      • getOwner

        public java.lang.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 java.util.HashSet 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​(java.util.HashSet 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 java.lang.Object clone()
        Creates and returns a copy of this object.
        Specified by:
        clone in interface SCO<E>
        Overrides:
        clone in class java.util.HashSet<E>
        Returns:
        The cloned object

      • contains

        public boolean contains​(java.lang.Object element)
        Accessor for whether an element is contained in this set.
        Specified by:
        contains in interface java.util.Collection<E>
        Specified by:
        contains in interface java.util.Set<E>
        Overrides:
        contains in class java.util.HashSet<E>
        Parameters:
        element - The element
        Returns:
        Whether it is contained.

      • containsAll

        public boolean containsAll​(java.util.Collection c)
        Accessor for whether a collection is contained in this set.
        Specified by:
        containsAll in interface java.util.Collection<E>
        Specified by:
        containsAll in interface java.util.Set<E>
        Overrides:
        containsAll in class java.util.AbstractCollection<E>
        Parameters:
        c - The collection
        Returns:
        Whether it is contained.

      • equals

        public boolean equals​(java.lang.Object o)
        Specified by:
        equals in interface java.util.Collection<E>
        Specified by:
        equals in interface java.util.Set<E>
        Overrides:
        equals in class java.util.AbstractSet<E>

      • hashCode

        public int hashCode()
        Specified by:
        hashCode in interface java.util.Collection<E>
        Specified by:
        hashCode in interface java.util.Set<E>
        Overrides:
        hashCode in class java.util.AbstractSet<E>

      • isEmpty

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

      • iterator

        public java.util.Iterator<E> iterator()
        Accessor for an iterator for the Set.
        Specified by:
        iterator in interface java.util.Collection<E>
        Specified by:
        iterator in interface java.lang.Iterable<E>
        Specified by:
        iterator in interface java.util.Set<E>
        Overrides:
        iterator in class java.util.HashSet<E>
        Returns:
        The iterator

      • size

        public int size()
        Accessor for the size of the HashSet.
        Specified by:
        size in interface java.util.Collection<E>
        Specified by:
        size in interface java.util.Set<E>
        Overrides:
        size in class java.util.HashSet<E>
        Returns:
        The size.

      • toArray

        public java.lang.Object[] toArray()
        Specified by:
        toArray in interface java.util.Collection<E>
        Specified by:
        toArray in interface java.util.Set<E>
        Overrides:
        toArray in class java.util.AbstractCollection<E>

      • toArray

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

      • add

        public boolean add​(E element)
        Method to add an element to the set.
        Specified by:
        add in interface java.util.Collection<E>
        Specified by:
        add in interface java.util.Set<E>
        Overrides:
        add in class java.util.HashSet<E>
        Parameters:
        element - The new element
        Returns:
        Whether it was added ok.

      • addAll

        public boolean addAll​(java.util.Collection<? extends E> elements)
        Method to add a collection to the set.
        Specified by:
        addAll in interface java.util.Collection<E>
        Specified by:
        addAll in interface java.util.Set<E>
        Overrides:
        addAll in class java.util.AbstractCollection<E>
        Parameters:
        elements - The collection
        Returns:
        Whether it was added ok.

      • clear

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

      • remove

        public boolean remove​(java.lang.Object element)
        Method to remove (the first occurrence of) an element from the collection
        Specified by:
        remove in interface java.util.Collection<E>
        Specified by:
        remove in interface java.util.Set<E>
        Overrides:
        remove in class java.util.HashSet<E>
        Parameters:
        element - The Element to remove
        Returns:
        Whether it was removed successfully.

      • remove

        public boolean remove​(java.lang.Object element,
                      boolean allowCascadeDelete)
        Method to remove (the first occurrence of) an element from the collection
        Specified by:
        remove in interface SCOCollection<java.util.HashSet<E>,​E>
        Parameters:
        element - The Element to remove
        allowCascadeDelete - Whether to cascade delete
        Returns:
        Whether it was removed successfully.

      • removeAll

        public boolean removeAll​(java.util.Collection elements)
        Method to remove all elements from the collection from the set.
        Specified by:
        removeAll in interface java.util.Collection<E>
        Specified by:
        removeAll in interface java.util.Set<E>
        Overrides:
        removeAll in class java.util.AbstractSet<E>
        Parameters:
        elements - The collection of elements to remove
        Returns:
        Whether it was removed ok.

      • retainAll

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

      • writeReplace

        protected java.lang.Object writeReplace()
                                 throws java.io.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:
        java.io.ObjectStreamException - if an error occurs

      • forEach

        public void forEach​(java.util.function.Consumer<? super E> action)
        Specified by:
        forEach in interface java.lang.Iterable<E>

      • stream

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

      • parallelStream

        public java.util.stream.Stream<E> parallelStream()
        Specified by:
        parallelStream in interface java.util.Collection<E>

      • spliterator

        public java.util.Spliterator spliterator()
        Specified by:
        spliterator in interface java.util.Collection<E>
        Specified by:
        spliterator in interface java.lang.Iterable<E>
        Specified by:
        spliterator in interface java.util.Set<E>
        Overrides:
        spliterator in class java.util.HashSet<E>