diff options
Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CollectionListValueModelAdapter.java')
| -rw-r--r-- | jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CollectionListValueModelAdapter.java | 309 |
1 files changed, 0 insertions, 309 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CollectionListValueModelAdapter.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CollectionListValueModelAdapter.java deleted file mode 100644 index 4f9dd20abc..0000000000 --- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CollectionListValueModelAdapter.java +++ /dev/null @@ -1,309 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2007 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.utility.internal.model.value; - -import java.util.ArrayList; -import java.util.Iterator; -import java.util.List; - -import org.eclipse.jpt.utility.internal.CollectionTools; -import org.eclipse.jpt.utility.internal.iterators.ReadOnlyListIterator; -import org.eclipse.jpt.utility.internal.model.AbstractModel; -import org.eclipse.jpt.utility.internal.model.ChangeSupport; -import org.eclipse.jpt.utility.internal.model.SingleAspectChangeSupport; -import org.eclipse.jpt.utility.internal.model.event.CollectionChangeEvent; -import org.eclipse.jpt.utility.internal.model.listener.CollectionChangeListener; -import org.eclipse.jpt.utility.internal.model.listener.ListChangeListener; - -/** - * An adapter that allows us to make a CollectionValueModel behave like - * a read-only ListValueModel, sorta. - * - * To maintain a reasonably consistent appearance to client code, we - * keep an internal list somewhat in synch with the wrapped collection. - * - * NB: Since we only listen to the wrapped collection when we have - * listeners ourselves and we can only stay in synch with the wrapped - * collection while we are listening to it, results to various methods - * (e.g. #size(), getItem(int)) will be unpredictable whenever - * we do not have any listeners. This should not be too painful since, - * most likely, client objects will also be listeners. - */ -public class CollectionListValueModelAdapter - extends AbstractModel - implements ListValueModel -{ - /** The wrapped collection value model. */ - protected final CollectionValueModel collectionHolder; - - /** A listener that forwards any events fired by the collection holder. */ - protected final CollectionChangeListener collectionChangeListener; - - /** - * Our internal list, which holds the same elements as - * the wrapped collection, but keeps them in order. - */ - // we declare this an ArrayList so we can use #clone() and #ensureCapacity(int) - protected final ArrayList list; - - - // ********** constructors ********** - - /** - * Wrap the specified CollectionValueModel. - */ - public CollectionListValueModelAdapter(CollectionValueModel collectionHolder) { - super(); - if (collectionHolder == null) { - throw new NullPointerException(); - } - this.collectionHolder = collectionHolder; - this.collectionChangeListener = this.buildCollectionChangeListener(); - this.list = new ArrayList(); - // postpone building the list and listening to the underlying collection - // until we have listeners ourselves... - } - - - // ********** initialization ********** - - @Override - protected ChangeSupport buildChangeSupport() { - return new SingleAspectChangeSupport(this, VALUE); - } - - /** - * The wrapped collection has changed, forward an equivalent - * list change event to our listeners. - */ - protected CollectionChangeListener buildCollectionChangeListener() { - return new CollectionChangeListener() { - public void itemsAdded(CollectionChangeEvent e) { - CollectionListValueModelAdapter.this.itemsAdded(e); - } - public void itemsRemoved(CollectionChangeEvent e) { - CollectionListValueModelAdapter.this.itemsRemoved(e); - } - public void collectionCleared(CollectionChangeEvent e) { - CollectionListValueModelAdapter.this.collectionCleared(e); - } - public void collectionChanged(CollectionChangeEvent e) { - CollectionListValueModelAdapter.this.collectionChanged(e); - } - @Override - public String toString() { - return "collection change listener"; - } - }; - } - - - // ********** ValueModel implementation ********** - - public Object value() { - // try to prevent backdoor modification of the list - return new ReadOnlyListIterator(this.list); - } - - - // ********** ListValueModel implementation ********** - - public void addItem(int index, Object item) { - throw new UnsupportedOperationException(); - } - - public void addItems(int index, List items) { - throw new UnsupportedOperationException(); - } - - public Object removeItem(int index) { - throw new UnsupportedOperationException(); - } - - public List removeItems(int index, int length) { - throw new UnsupportedOperationException(); - } - - public Object replaceItem(int index, Object item) { - throw new UnsupportedOperationException(); - } - - public List replaceItems(int index, List items) { - throw new UnsupportedOperationException(); - } - - public Object getItem(int index) { - return this.list.get(index); - } - - public int size() { - return this.list.size(); - } - - - // ********** extend change support ********** - - /** - * Override to start listening to the collection holder if necessary. - */ - @Override - public void addListChangeListener(ListChangeListener listener) { - if (this.hasNoListeners()) { - this.engageModel(); - } - super.addListChangeListener(listener); - } - - /** - * Override to start listening to the collection holder if necessary. - */ - @Override - public void addListChangeListener(String listName, ListChangeListener listener) { - if (listName == VALUE && this.hasNoListeners()) { - this.engageModel(); - } - super.addListChangeListener(listName, listener); - } - - /** - * Override to stop listening to the collection holder if appropriate. - */ - @Override - public void removeListChangeListener(ListChangeListener listener) { - super.removeListChangeListener(listener); - if (this.hasNoListeners()) { - this.disengageModel(); - } - } - - /** - * Override to stop listening to the collection holder if appropriate. - */ - @Override - public void removeListChangeListener(String listName, ListChangeListener listener) { - super.removeListChangeListener(listName, listener); - if (listName == VALUE && this.hasNoListeners()) { - this.disengageModel(); - } - } - - - // ********** queries ********** - - protected boolean hasListeners() { - return this.hasAnyListChangeListeners(VALUE); - } - - protected boolean hasNoListeners() { - return ! this.hasListeners(); - } - - /** - * Return the index of the specified item, using object - * identity instead of equality. - */ - protected int lastIdentityIndexOf(Object o) { - return this.lastIdentityIndexOf(o, this.list.size()); - } - - /** - * Return the last index of the specified item, starting just before the - * the specified endpoint, and using object identity instead of equality. - */ - protected int lastIdentityIndexOf(Object o, int end) { - for (int i = end; i-- > 0; ) { - if (this.list.get(i) == o) { - return i; - } - } - return -1; - } - - - // ********** behavior ********** - - protected void buildList() { - Iterator stream = (Iterator) this.collectionHolder.values(); - // if the new collection is empty, do nothing - if (stream.hasNext()) { - this.list.ensureCapacity(this.collectionHolder.size()); - while (stream.hasNext()) { - this.list.add(stream.next()); - } - this.postBuildList(); - } - } - - /** - * Allow subclasses to manipulate the internal list before - * sending out change notification. - */ - protected void postBuildList() { - // the default is to do nothing... - } - - protected void engageModel() { - this.collectionHolder.addCollectionChangeListener(CollectionValueModel.VALUES, this.collectionChangeListener); - // synch our list *after* we start listening to the collection holder, - // since its value might change when a listener is added - this.buildList(); - } - - protected void disengageModel() { - this.collectionHolder.removeCollectionChangeListener(CollectionValueModel.VALUES, this.collectionChangeListener); - // clear out the list when we are not listening to the collection holder - this.list.clear(); - } - - protected void itemsAdded(CollectionChangeEvent e) { - this.addItemsToList(this.indexToAddItems(), CollectionTools.list(e.items()), this.list, VALUE); - } - - protected int indexToAddItems() { - return this.list.size(); - } - - protected void itemsRemoved(CollectionChangeEvent e) { - // we have to remove the items individually, - // since they are probably not in sequence - for (Iterator stream = e.items(); stream.hasNext(); ) { - this.removeItemFromList(this.lastIdentityIndexOf(stream.next()), this.list, VALUE); - } - } - - protected void collectionCleared(CollectionChangeEvent e) { - this.clearList(this.list, VALUE); - } - - /** - * synchronize our internal list with the wrapped collection - * and fire the appropriate events - */ - protected void collectionChanged(CollectionChangeEvent e) { - // put in empty check so we don't fire events unnecessarily - if ( ! this.list.isEmpty()) { - ArrayList removedItems = (ArrayList) this.list.clone(); - this.list.clear(); - this.fireItemsRemoved(VALUE, 0, removedItems); - } - - this.buildList(); - // put in empty check so we don't fire events unnecessarily - if ( ! this.list.isEmpty()) { - this.fireItemsAdded(VALUE, 0, this.list); - } - } - - @Override - public void toString(StringBuilder sb) { - sb.append(this.collectionHolder); - } - -} |