/*******************************************************************************
* Copyright (c) 2008, 2015 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
* Stefan Xenos <sxenos@gmail.com> - Bug 335792
******************************************************************************/
package org.eclipse.core.databinding.property.map;
import java.util.Collections;
import java.util.Map;
import org.eclipse.core.databinding.observable.Diffs;
import org.eclipse.core.databinding.observable.Realm;
import org.eclipse.core.databinding.observable.map.IObservableMap;
import org.eclipse.core.databinding.observable.map.MapDiff;
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.identity.IdentityMap;
import org.eclipse.core.internal.databinding.property.MapPropertyDetailValuesMap;
/**
* Abstract implementation of IMapProperty
*
* @param <S>
* type of the source object
* @param <K>
* type of the keys to the map
* @param <V>
* type of the values in the map
* @since 1.2
*/
public abstract class MapProperty<S, K, V> implements IMapProperty<S, K, V> {
/**
* By default, this method returns <code>Collections.EMPTY_MAP</code> in
* case the source object is <code>null</code>. Otherwise, this method
* delegates to {@link #doGetMap(Object)}.
*
* <p>
* Clients may override this method if they e.g. want to return a specific
* default map in case the source object is <code>null</code>.
* </p>
*
* @see #doGetMap(Object)
*
* @since 1.3
*/
@Override
public Map<K, V> getMap(S source) {
if (source == null) {
return Collections.emptyMap();
}
return Collections.unmodifiableMap(doGetMap(source));
}
/**
* Returns a Map with the current contents of the source's map property
*
* @param source
* the property source
* @return a Map with the current contents of the source's map property
* @since 1.6
* @noreference This method is not intended to be referenced by clients.
*/
protected Map<K, V> doGetMap(S source) {
IObservableMap<K, V> observable = observe(source);
try {
return new IdentityMap<>(observable);
} finally {
observable.dispose();
}
}
/**
* @since 1.3
*/
@Override
public final void setMap(S source, Map<K, V> map) {
if (source != null) {
doSetMap(source, map);
}
}
/**
* Updates the property on the source with the specified change.
*
* @param source
* the property source
* @param map
* the new map
* @since 1.6
* @noreference This method is not intended to be referenced by clients.
*/
protected void doSetMap(S source, Map<K, V> map) {
MapDiff<K, V> diff = Diffs.computeMapDiff(doGetMap(source), map);
doUpdateMap(source, diff);
}
/**
* @since 1.3
*/
@Override
public final void updateMap(S source, MapDiff<K, V> diff) {
if (source != null) {
doUpdateMap(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 1.6
* @noreference This method is not intended to be referenced by clients.
*/
protected void doUpdateMap(S source, MapDiff<K, V> diff) {
IObservableMap<K, V> observable = observe(source);
try {
diff.applyTo(observable);
} finally {
observable.dispose();
}
}
@Override
public IObservableMap<K, V> observe(S source) {
return observe(Realm.getDefault(), source);
}
@Override
public IObservableFactory<S, IObservableMap<K, V>> mapFactory() {
return new IObservableFactory<S, IObservableMap<K, V>>() {
@Override
public IObservableMap<K, V> createObservable(S target) {
return observe(target);
}
};
}
@Override
public IObservableFactory<S, IObservableMap<K, V>> mapFactory(final Realm realm) {
return new IObservableFactory<S, IObservableMap<K, V>>() {
@Override
public IObservableMap<K, V> createObservable(S target) {
return observe(realm, target);
}
};
}
@Override
public <U extends S> IObservableMap<K, V> observeDetail(IObservableValue<U> master) {
return MasterDetailObservables.detailMap(master, mapFactory(master.getRealm()), getKeyType(), getValueType());
}
@Override
public final <T> IMapProperty<S, K, T> values(IValueProperty<? super V, T> detailValues) {
return new MapPropertyDetailValuesMap<S, K, V, T>(this, detailValues);
}
}