| /******************************************************************************* |
| * Copyright (c) 2008, 2010 Matthew Hall and others. |
| * 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: |
| * Matthew Hall - initial API and implementation (bug 194734) |
| * Matthew Hall - bug 195222 |
| * Ovidio Mallo - bug 331348 |
| ******************************************************************************/ |
| |
| package org.eclipse.core.databinding.property.list; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.eclipse.core.databinding.observable.Diffs; |
| import org.eclipse.core.databinding.observable.Realm; |
| import org.eclipse.core.databinding.observable.list.IObservableList; |
| import org.eclipse.core.databinding.observable.list.ListDiff; |
| import org.eclipse.core.databinding.observable.masterdetail.IObservableFactory; |
| import org.eclipse.core.databinding.observable.masterdetail.MasterDetailObservables; |
| import org.eclipse.core.databinding.observable.value.IObservableValue; |
| import org.eclipse.core.databinding.property.value.IValueProperty; |
| import org.eclipse.core.internal.databinding.property.ListPropertyDetailValuesList; |
| |
| /** |
| * Abstract implementation of IListProperty. |
| * |
| * @param <S> |
| * type of the source object |
| * @param <E> |
| * type of the elements in the list |
| * @since 1.2 |
| */ |
| public abstract class ListProperty<S, E> implements IListProperty<S, E> { |
| |
| /** |
| * By default, this method returns <code>Collections.EMPTY_LIST</code> in |
| * case the source object is <code>null</code>. Otherwise, this method |
| * delegates to {@link #doGetList(Object)}. |
| * |
| * <p> |
| * Clients may override this method if they e.g. want to return a specific |
| * default list in case the source object is <code>null</code>. |
| * </p> |
| * |
| * @see #doGetList(Object) |
| * |
| * @since 1.3 |
| */ |
| public List<E> getList(S source) { |
| if (source == null) { |
| return Collections.emptyList(); |
| } |
| return Collections.unmodifiableList(doGetList(source)); |
| } |
| |
| /** |
| * Returns a List with the current contents of the source's list property |
| * |
| * @param source |
| * the property source |
| * @return a List with the current contents of the source's list property |
| * @noreference This method is not intended to be referenced by clients. |
| * @since 1.5 |
| */ |
| protected List<E> doGetList(S source) { |
| IObservableList<E> observable = observe(source); |
| try { |
| return new ArrayList<E>(observable); |
| } finally { |
| observable.dispose(); |
| } |
| } |
| |
| /** |
| * @since 1.3 |
| */ |
| public final void setList(S source, List<E> list) { |
| if (source != null) { |
| doSetList(source, list); |
| } |
| } |
| |
| /** |
| * Updates the property on the source with the specified change. |
| * |
| * @param source |
| * the property source |
| * @param list |
| * the new list |
| * @since 1.5 |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| protected void doSetList(S source, List<E> list) { |
| doUpdateList(source, Diffs.computeListDiff(doGetList(source), list)); |
| } |
| |
| /** |
| * @since 1.3 |
| */ |
| public final void updateList(S source, ListDiff<E> diff) { |
| if (source != null) { |
| doUpdateList(source, diff); |
| } |
| } |
| |
| /** |
| * Updates the property on the source with the specified change |
| * |
| * @param source |
| * the property source |
| * @param diff |
| * a diff describing the change |
| * @since 1.3 |
| */ |
| protected void doUpdateList(S source, ListDiff<E> diff) { |
| IObservableList<E> observable = observe(source); |
| try { |
| diff.applyTo(observable); |
| } finally { |
| observable.dispose(); |
| } |
| } |
| |
| public IObservableList<E> observe(S source) { |
| return observe(Realm.getDefault(), source); |
| } |
| |
| public IObservableFactory<S, IObservableList<E>> listFactory() { |
| return new IObservableFactory<S, IObservableList<E>>() { |
| public IObservableList<E> createObservable(S target) { |
| return observe(target); |
| } |
| }; |
| } |
| |
| public IObservableFactory<S, IObservableList<E>> listFactory( |
| final Realm realm) { |
| return new IObservableFactory<S, IObservableList<E>>() { |
| public IObservableList<E> createObservable(S target) { |
| return observe(realm, target); |
| } |
| }; |
| } |
| |
| public <U extends S> IObservableList<E> observeDetail( |
| IObservableValue<U> master) { |
| return MasterDetailObservables.detailList(master, |
| listFactory(master.getRealm()), getElementClass()); |
| } |
| |
| public final <T> IListProperty<S, T> values( |
| IValueProperty<? super E, T> detailValue) { |
| return new ListPropertyDetailValuesList<S, E, T>(this, detailValue); |
| } |
| |
| /** |
| * This is a default implementation that should ideally be overridden to use |
| * a properly typed Class field. This implementation checks to see if the |
| * element type is of type Class and, if it is, it assumes it is the class |
| * of the elements and makes an unchecked cast. |
| * <P> |
| * This method should always be overridden to provide an implementation that |
| * never returns null. |
| * |
| * @return the class of the elements, if possible, or null if this is not |
| * possible |
| * @since 1.5 |
| */ |
| public Class<E> getElementClass() { |
| Object elementType = getElementType(); |
| if (elementType instanceof Class) { |
| return (Class<E>) elementType; |
| } |
| return null; |
| } |
| } |