Module org.eclipse.persistence.jpa.jpql
Package org.eclipse.persistence.jpa.jpql.tools.utility.iterator

Class CloneIterator<E>

java.lang.Object
org.eclipse.persistence.jpa.jpql.tools.utility.iterator.CloneIterator<E>
Type Parameters:
E - the type of elements returned by the iterator
All Implemented Interfaces:
Iterator<E>
Direct Known Subclasses:
SnapshotCloneIterable.LocalCloneIterator
public class CloneIterator<E> extends Object implements Iterator<E>
A CloneIterator iterates over a copy of a collection, allowing for concurrent access to the original collection.

The original collection passed to the CloneIterator's constructor should be synchronized (e.g. Vector); otherwise you run the risk of a corrupted collection.

By default, a CloneIterator does not support the remove() operation; this is because it does not have access to the original collection. But if the CloneIterator is supplied with an CloneIterator.Remover it will delegate the remove() operation to the CloneIterator.Remover. Alternatively, a subclass can override the remove(Object) method.

See Also:

  • Constructor Details

    • CloneIterator

      public CloneIterator(Collection<? extends E> collection)
      Construct an iterator on a copy of the specified collection. The remove() method will not be supported, unless a subclass overrides the remove(Object).

    • CloneIterator

      public CloneIterator(E[] array)
      Construct an iterator on a copy of the specified array. The remove() method will not be supported, unless a subclass overrides the remove(Object).

    • CloneIterator

      public CloneIterator(Collection<? extends E> collection, CloneIterator.Remover<E> remover)
      Construct an iterator on a copy of the specified collection. Use the specified remover to remove objects from the original collection.

    • CloneIterator

      public CloneIterator(E[] array, CloneIterator.Remover<E> remover)
      Construct an iterator on a copy of the specified array. Use the specified remover to remove objects from the original array.

    • CloneIterator

      protected CloneIterator(CloneIterator.Remover<E> remover, Object... array)
      Internal constructor used by subclasses. Swap order of arguments to prevent collision with other constructor. The passed in array will *not* be cloned.

  • Method Details

    • hasNext

      public boolean hasNext()
      Specified by:
      hasNext in interface Iterator<E>

    • next

      public E next()
      Specified by:
      next in interface Iterator<E>

    • remove

      public void remove()
      Specified by:
      remove in interface Iterator<E>

    • nestedNext

      protected E nestedNext()
      The collection passed in during construction held elements of type E, so this cast is not a problem. We need this cast because all the elements of the original collection were copied into an object array (Object[]).

    • remove

      protected void remove(E e)
      Remove the specified element from the original collection.

      This method can be overridden by a subclass as an alternative to building a CloneIterator.Remover.