diff options
Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/ListCollectionValueModelAdapter.java')
| -rw-r--r-- | jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/ListCollectionValueModelAdapter.java | 302 |
1 files changed, 0 insertions, 302 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/ListCollectionValueModelAdapter.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/ListCollectionValueModelAdapter.java deleted file mode 100644 index 73ef86d495..0000000000 --- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/ListCollectionValueModelAdapter.java +++ /dev/null @@ -1,302 +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.Collection; -import java.util.Iterator; - -import org.eclipse.jpt.utility.internal.iterators.ReadOnlyIterator; -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.ListChangeEvent; -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 ListValueModel behave like - * a read-only CollectionValueModel, sorta. - * - * We keep an internal collection somewhat in synch with the wrapped list. - * - * NB: Since we only listen to the wrapped list when we have - * listeners ourselves and we can only stay in synch with the wrapped - * list while we are listening to it, results to various methods - * (e.g. #size(), value()) 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 ListCollectionValueModelAdapter - extends AbstractModel - implements CollectionValueModel -{ - /** The wrapped list value model. */ - protected final ListValueModel listHolder; - - /** A listener that forwards any events fired by the list holder. */ - protected final ListChangeListener listChangeListener; - - /** - * Our internal collection, which holds the same elements as - * the wrapped list. - */ - // we declare this an ArrayList so we can use #clone() and #ensureCapacity(int) - protected final ArrayList collection; - - - // ********** constructors/initialization ********** - - /** - * Wrap the specified ListValueModel. - */ - public ListCollectionValueModelAdapter(ListValueModel listHolder) { - super(); - if (listHolder == null) { - throw new NullPointerException(); - } - this.listHolder = listHolder; - this.listChangeListener = this.buildListChangeListener(); - this.collection = new ArrayList(); - // postpone building the collection and listening to the underlying list - // until we have listeners ourselves... - } - - @Override - protected ChangeSupport buildChangeSupport() { - return new SingleAspectChangeSupport(this, VALUES); - } - - /** - * The wrapped list has changed, forward an equivalent - * collection change event to our listeners. - */ - protected ListChangeListener buildListChangeListener() { - return new ListChangeListener() { - public void itemsAdded(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.itemsAdded(e); - } - public void itemsRemoved(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.itemsRemoved(e); - } - public void itemsReplaced(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.itemsReplaced(e); - } - public void itemsMoved(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.itemsMoved(e); - } - public void listCleared(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.listCleared(e); - } - public void listChanged(ListChangeEvent e) { - ListCollectionValueModelAdapter.this.listChanged(e); - } - @Override - public String toString() { - return "list change listener"; - } - }; - } - - - // ********** CollectionValueModel implementation ********** - - public Iterator values() { - // try to prevent backdoor modification of the list - return new ReadOnlyIterator(this.collection); - } - - public void add(Object item) { - throw new UnsupportedOperationException(); - } - - public void addAll(Collection items) { - throw new UnsupportedOperationException(); - } - - public void remove(Object item) { - throw new UnsupportedOperationException(); - } - - public void removeAll(Collection items) { - throw new UnsupportedOperationException(); - } - - public int size() { - return this.collection.size(); - } - - - // ********** extend change support ********** - - /** - * Override to start listening to the list holder if necessary. - */ - @Override - public void addCollectionChangeListener(CollectionChangeListener listener) { - if (this.hasNoListeners()) { - this.engageModel(); - } - super.addCollectionChangeListener(listener); - } - - /** - * Override to start listening to the list holder if necessary. - */ - @Override - public void addCollectionChangeListener(String collectionName, CollectionChangeListener listener) { - if (collectionName == VALUES && this.hasNoListeners()) { - this.engageModel(); - } - super.addCollectionChangeListener(collectionName, listener); - } - - /** - * Override to stop listening to the list holder if appropriate. - */ - @Override - public void removeCollectionChangeListener(CollectionChangeListener listener) { - super.removeCollectionChangeListener(listener); - if (this.hasNoListeners()) { - this.disengageModel(); - } - } - - /** - * Override to stop listening to the list holder if appropriate. - */ - @Override - public void removeCollectionChangeListener(String collectionName, CollectionChangeListener listener) { - super.removeCollectionChangeListener(collectionName, listener); - if (collectionName == VALUES && this.hasNoListeners()) { - this.disengageModel(); - } - } - - - // ********** queries ********** - - protected boolean hasListeners() { - return this.hasAnyCollectionChangeListeners(VALUES); - } - - 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.collection.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.collection.get(i) == o) { - return i; - } - } - return -1; - } - - - // ********** behavior ********** - - protected void buildCollection() { - Iterator stream = (Iterator) this.listHolder.value(); - // if the new list is empty, do nothing - if (stream.hasNext()) { - this.collection.ensureCapacity(this.listHolder.size()); - while (stream.hasNext()) { - this.collection.add(stream.next()); - } - } - } - - protected void engageModel() { - this.listHolder.addListChangeListener(ValueModel.VALUE, this.listChangeListener); - // synch our collection *after* we start listening to the list holder, - // since its value might change when a listener is added - this.buildCollection(); - } - - protected void disengageModel() { - this.listHolder.removeListChangeListener(ValueModel.VALUE, this.listChangeListener); - // clear out the collection when we are not listening to the list holder - this.collection.clear(); - } - - protected void itemsAdded(ListChangeEvent e) { - this.addItemsToCollection(e.items(), this.collection, VALUES); - } - - protected void removeInternalItems(Iterator items) { - // we have to remove the items individually, - // since they are probably not in sequence - while (items.hasNext()) { - Object removedItem = items.next(); - int index = this.lastIdentityIndexOf(removedItem); - this.collection.remove(index); - this.fireItemRemoved(VALUES, removedItem); - } - } - - protected void itemsRemoved(ListChangeEvent e) { - this.removeInternalItems(e.items()); - } - - protected void itemsReplaced(ListChangeEvent e) { - this.removeInternalItems(e.replacedItems()); - this.addItemsToCollection(e.items(), this.collection, VALUES); - } - - protected void itemsMoved(ListChangeEvent e) { - // do nothing? moving items in a list has no net effect on a collection... - } - - protected void listCleared(ListChangeEvent e) { - // put in empty check so we don't fire events unnecessarily - if ( ! this.collection.isEmpty()) { - this.collection.clear(); - this.fireCollectionCleared(VALUES); - } - } - - /** - * synchronize our internal collection with the wrapped list - * and fire the appropriate events - */ - protected void listChanged(ListChangeEvent e) { - // put in empty check so we don't fire events unnecessarily - if ( ! this.collection.isEmpty()) { - ArrayList removedItems = (ArrayList) this.collection.clone(); - this.collection.clear(); - this.fireItemsRemoved(VALUES, removedItems); - } - - this.buildCollection(); - // put in empty check so we don't fire events unnecessarily - if ( ! this.collection.isEmpty()) { - this.fireItemsAdded(VALUES, this.collection); - } - } - - @Override - public void toString(StringBuilder sb) { - sb.append(this.listHolder); - } - -} |