| /******************************************************************************* |
| * Copyright (c) 2009 Oracle. All rights reserved. |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0, which accompanies this distribution |
| * and is available at http://www.eclipse.org/legal/epl-v10.html. |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| ******************************************************************************/ |
| package org.eclipse.jpt.common.utility.internal.iterables; |
| |
| import java.util.List; |
| import java.util.ListIterator; |
| |
| import org.eclipse.jpt.common.utility.internal.StringTools; |
| import org.eclipse.jpt.common.utility.internal.iterators.CloneListIterator; |
| |
| /** |
| * A <code>LiveCloneListIterable</code> returns a list iterator on a current |
| * copy of a list, allowing for concurrent access to the original list. A |
| * copy of the list is created every time {@link #iterator()} is |
| * called. As a result, the contents of the list can be different with |
| * each call to {@link #iterator()} (i.e. it is "live"). |
| * <p> |
| * The original list passed to the <code>LiveCloneListIterable</code>'s |
| * constructor should be thread-safe (e.g. {@link java.util.Vector}); |
| * otherwise you run the risk of a corrupted list. |
| * <p> |
| * By default, the list iterator returned by a <code>LiveCloneListIterable</code> |
| * does not support the modify operations; this is because it does not |
| * have access to the original list. But if the <code>LiveCloneListIterable</code> |
| * is supplied with an {@link CloneListIterator.Mutator} it will delegate the |
| * modify operations to the <code>Mutator</code>. |
| * Alternatively, a subclass can override the list iterable's mutation |
| * methods. |
| * |
| * @param <E> the type of elements returned by the list iterable's list iterator |
| * |
| * @see CloneListIterator |
| * @see SnapshotCloneListIterable |
| * @see LiveCloneIterable |
| */ |
| public class LiveCloneListIterable<E> |
| extends CloneListIterable<E> |
| { |
| private final List<? extends E> list; |
| |
| |
| // ********** constructors ********** |
| |
| /** |
| * Construct a "live" list iterable for the specified list. |
| * The {@link ListIterator} mutation operations will not be supported |
| * by the list iterator returned by {@link #iterator()} |
| * unless a subclass overrides the iterable's mutation |
| * methods. |
| */ |
| public LiveCloneListIterable(List<? extends E> list) { |
| super(); |
| this.list = list; |
| } |
| |
| /** |
| * Construct a "live" list iterable for the specified list. |
| * The specified mutator will be used by any generated list iterators to |
| * modify the original list. |
| */ |
| public LiveCloneListIterable(List<? extends E> list, CloneListIterator.Mutator<E> mutator) { |
| super(mutator); |
| this.list = list; |
| } |
| |
| |
| // ********** ListIterable implementation ********** |
| |
| public ListIterator<E> iterator() { |
| return new CloneListIterator<E>(this.list, this.mutator); |
| } |
| |
| @Override |
| public String toString() { |
| return StringTools.buildToStringFor(this, this.list); |
| } |
| |
| } |