| /******************************************************************************* |
| * 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 247997) |
| * Matthew Hall - bug 264306 |
| ******************************************************************************/ |
| |
| package org.eclipse.core.databinding.property.value; |
| |
| import org.eclipse.core.databinding.observable.Realm; |
| import org.eclipse.core.databinding.observable.list.IObservableList; |
| import org.eclipse.core.databinding.observable.map.IObservableMap; |
| import org.eclipse.core.databinding.observable.set.IObservableSet; |
| import org.eclipse.core.databinding.observable.value.IObservableValue; |
| import org.eclipse.core.databinding.observable.value.ValueDiff; |
| import org.eclipse.core.databinding.property.INativePropertyListener; |
| import org.eclipse.core.databinding.property.ISimplePropertyListener; |
| import org.eclipse.core.internal.databinding.property.value.ListDelegatingValueObservableList; |
| import org.eclipse.core.internal.databinding.property.value.MapDelegatingValueObservableMap; |
| import org.eclipse.core.internal.databinding.property.value.SetDelegatingValueObservableMap; |
| |
| /** |
| * @param <S> |
| * type of the source object |
| * @param <T> |
| * type of the value of the property |
| * @since 1.2 |
| * |
| */ |
| public abstract class DelegatingValueProperty<S, T> extends ValueProperty<S, T> { |
| private final Object valueTypeAsObject; |
| private final Class<T> valueType; |
| private final IValueProperty<S, T> nullProperty = new NullValueProperty(); |
| |
| protected DelegatingValueProperty() { |
| this(null); |
| } |
| |
| /** |
| * |
| * @param valueType |
| * @deprecated use the constructor that takes a Class object instead |
| */ |
| protected DelegatingValueProperty(Object valueType) { |
| this.valueType = null; |
| this.valueTypeAsObject = valueType; |
| } |
| |
| /** |
| * @param valueType |
| * @since 1.5 |
| */ |
| protected DelegatingValueProperty(Class<T> valueType) { |
| this.valueType = valueType; |
| this.valueTypeAsObject = valueType; |
| } |
| |
| /** |
| * Returns the property to delegate to for the specified source object. |
| * Repeated calls to this method with the same source object returns the |
| * same delegate instance. |
| * |
| * @param source |
| * the property source (may be null) |
| * @return the property to delegate to for the specified source object. |
| */ |
| public final IValueProperty<S, T> getDelegate(S source) { |
| if (source == null) |
| return nullProperty; |
| IValueProperty<S, T> delegate = doGetDelegate(source); |
| if (delegate == null) |
| delegate = nullProperty; |
| return delegate; |
| } |
| |
| /** |
| * Returns the property to delegate to for the specified source object. |
| * Implementers must ensure that repeated calls to this method with the same |
| * source object returns the same delegate instance. |
| * |
| * @param source |
| * the property source |
| * @return the property to delegate to for the specified source object. |
| */ |
| protected abstract IValueProperty<S, T> doGetDelegate(S source); |
| |
| protected T doGetValue(S source) { |
| return getDelegate(source).getValue(source); |
| } |
| |
| protected void doSetValue(S source, T value) { |
| getDelegate(source).setValue(source, value); |
| } |
| |
| public Object getValueType() { |
| return valueTypeAsObject; |
| } |
| |
| /** |
| * @since 1.5 |
| */ |
| public Class<T> getValueClass() { |
| return valueType; |
| } |
| |
| public IObservableValue<T> observe(S source) { |
| return getDelegate(source).observe(source); |
| } |
| |
| public IObservableValue<T> observe(Realm realm, S source) { |
| return getDelegate(source).observe(realm, source); |
| } |
| |
| public <U extends S> IObservableList<T> observeDetail( |
| IObservableList<U> master) { |
| return new ListDelegatingValueObservableList<S, U, T>(master, this); |
| } |
| |
| public <U extends S> IObservableMap<U, T> observeDetail( |
| IObservableSet<U> master) { |
| return new SetDelegatingValueObservableMap<S, U, T>(master, this); |
| } |
| |
| public <K, V extends S> IObservableMap<K, T> observeDetail( |
| IObservableMap<K, V> master) { |
| return new MapDelegatingValueObservableMap<S, K, V, T>(master, this); |
| } |
| |
| private class NullValueProperty extends SimpleValueProperty<S, T> { |
| public Object getValueType() { |
| return valueType; |
| } |
| |
| public Class<T> getValueClass() { |
| return valueType; |
| } |
| |
| protected T doGetValue(S source) { |
| return null; |
| } |
| |
| protected void doSetValue(S source, T value) { |
| } |
| |
| public INativePropertyListener<S> adaptListener( |
| ISimplePropertyListener<ValueDiff<T>> listener) { |
| return null; |
| } |
| } |
| } |