org.eclipse.persistence.jpa.jpql.tools.utility.iterable

Class SnapshotCloneIterable<E>

java.lang.Object

org.eclipse.persistence.jpa.jpql.tools.utility.iterable.CloneIterable<E>

org.eclipse.persistence.jpa.jpql.tools.utility.iterable.SnapshotCloneIterable<E>

Type Parameters:

E - the type of elements returned by the iterable's iterator

All Implemented Interfaces:

java.lang.Iterable<E>

public class SnapshotCloneIterable<E>
extends CloneIterable<E>

A SnapshotCloneIterable returns an iterator on a "snapshot" of a collection, allowing for concurrent access to the original collection. A copy of the collection is created when the iterable is constructed. As a result, the contents of the collection will be the same with every call to iterator().

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

By default, the iterator returned by a SnapshotCloneIterable does not support the Iterator.remove() operation; this is because it does not have access to the original collection. But if the SnapshotCloneIterable is supplied with a CloneIterator.Remover it will delegate the Iterator.remove() operation to the Remover. Alternatively, a subclass can override the iterable's CloneIterable.remove(Object) method.

This iterable is useful for multiple passes over a collection that should not be changed (e.g. by another thread) between passes.

See Also:

CloneIterator, LiveCloneIterable, SnapshotCloneListIterable

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	SnapshotCloneIterable.LocalCloneIterator<E> provide access to "internal" constructor

Nested classes/interfaces inherited from class org.eclipse.persistence.jpa.jpql.tools.utility.iterable.CloneIterable

CloneIterable.DefaultRemover

Constructor Summary

Constructors

Constructor and Description
SnapshotCloneIterable(java.util.Collection<? extends E> collection) Construct a "snapshot" iterable for the specified collection.
SnapshotCloneIterable(java.util.Collection<? extends E> collection, CloneIterator.Remover<E> remover) Construct a "snapshot" iterable for the specified collection.
SnapshotCloneIterable(java.util.Iterator<? extends E> iterator) Construct a "snapshot" iterable for the specified iterator.
SnapshotCloneIterable(java.util.Iterator<? extends E> iterator, CloneIterator.Remover<E> remover) Construct a "snapshot" iterable for the specified iterator.

Method Summary

Modifier and Type	Method and Description
java.util.Iterator<E>	iterator()
java.lang.String	toString()

Methods inherited from class org.eclipse.persistence.jpa.jpql.tools.utility.iterable.CloneIterable

buildDefaultRemover, remove

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

SnapshotCloneIterable

public SnapshotCloneIterable(java.util.Iterator<? extends E> iterator)

Construct a "snapshot" iterable for the specified iterator. The Iterator.remove() operation will not be supported by the iterator returned by iterator() unless a subclass overrides the iterable's CloneIterable.remove(Object) method.

SnapshotCloneIterable

public SnapshotCloneIterable(java.util.Iterator<? extends E> iterator,
                             CloneIterator.Remover<E> remover)

Construct a "snapshot" iterable for the specified iterator. The specified remover will be used by any generated iterators to remove objects from the original collection.

SnapshotCloneIterable

public SnapshotCloneIterable(java.util.Collection<? extends E> collection)

Construct a "snapshot" iterable for the specified collection. The Iterator.remove() operation will not be supported by the iterator returned by iterator() unless a subclass overrides the iterable's CloneIterable.remove(Object) method.

SnapshotCloneIterable

public SnapshotCloneIterable(java.util.Collection<? extends E> collection,
                             CloneIterator.Remover<E> remover)

Construct a "snapshot" iterable for the specified collection. The specified remover will be used by any generated iterators to remove objects from the original collection.

Method Detail

iterator

public java.util.Iterator<E> iterator()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object