/*******************************************************************************
* 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 262269
* Stefan Xenos <sxenos@gmail.com> - Bug 335792
******************************************************************************/
package org.eclipse.core.internal.databinding.property.value;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import org.eclipse.core.databinding.observable.Diffs;
import org.eclipse.core.databinding.observable.IStaleListener;
import org.eclipse.core.databinding.observable.ObservableTracker;
import org.eclipse.core.databinding.observable.StaleEvent;
import org.eclipse.core.databinding.observable.list.AbstractObservableList;
import org.eclipse.core.databinding.observable.list.IListChangeListener;
import org.eclipse.core.databinding.observable.list.IObservableList;
import org.eclipse.core.databinding.observable.list.ListChangeEvent;
import org.eclipse.core.databinding.observable.list.ListDiff;
import org.eclipse.core.databinding.observable.list.ListDiffEntry;
import org.eclipse.core.databinding.property.IPropertyObservable;
import org.eclipse.core.databinding.property.value.DelegatingValueProperty;
/**
* @param <S>
* type of the source object
* @param <T>
* type of the value of the property
* @param <E>
* type of the elements in the list
* @since 1.2
*/
public class ListDelegatingValueObservableList<S, T extends S, E> extends AbstractObservableList<E>
implements IPropertyObservable<DelegatingValueProperty<S, E>> {
private IObservableList<T> masterList;
private DelegatingValueProperty<S, E> detailProperty;
private DelegatingCache<S, T, E> cache;
private IListChangeListener<T> masterListener = new IListChangeListener<T>() {
@Override
public void handleListChange(ListChangeEvent<? extends T> event) {
if (isDisposed())
return;
cache.addAll(masterList);
// Need both obsolete and new elements to convert diff
ListDiff<E> diff = convertDiff(event.diff);
cache.retainAll(masterList);
fireListChange(diff);
}
private ListDiff<E> convertDiff(ListDiff<? extends T> diff) {
// Convert diff to detail value
ListDiffEntry<? extends T>[] masterEntries = diff.getDifferences();
List<ListDiffEntry<E>> detailEntries = new ArrayList<>(masterEntries.length);
for (ListDiffEntry<? extends T> masterDifference : masterEntries) {
int index = masterDifference.getPosition();
boolean addition = masterDifference.isAddition();
T masterElement = masterDifference.getElement();
E detailValue = cache.get(masterElement);
detailEntries.add(Diffs.createListDiffEntry(index, addition, detailValue));
}
return Diffs.createListDiff(detailEntries);
}
};
private IStaleListener staleListener = new IStaleListener() {
@Override
public void handleStale(StaleEvent staleEvent) {
fireStale();
}
};
/**
* @param masterList
* @param valueProperty
*/
public ListDelegatingValueObservableList(IObservableList<T> masterList,
DelegatingValueProperty<S, E> valueProperty) {
super(masterList.getRealm());
this.masterList = masterList;
this.detailProperty = valueProperty;
this.cache = new DelegatingCache<S, T, E>(getRealm(), valueProperty) {
@Override
void handleValueChange(T masterElement, E oldValue, E newValue) {
fireListChange(indicesOf(masterElement), oldValue, newValue);
}
};
cache.addAll(masterList);
masterList.addListChangeListener(masterListener);
masterList.addStaleListener(staleListener);
}
@Override
protected int doGetSize() {
getterCalled();
return masterList.size();
}
private void getterCalled() {
ObservableTracker.getterCalled(this);
}
@Override
public E get(int index) {
getterCalled();
T masterElement = masterList.get(index);
return cache.get(masterElement);
}
@Override
public boolean add(Object o) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(Collection<? extends E> c) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(int index, Collection<? extends E> c) {
throw new UnsupportedOperationException();
}
@Override
public boolean contains(Object o) {
getterCalled();
return cache.containsValue(o);
}
@Override
public boolean isEmpty() {
getterCalled();
return masterList.isEmpty();
}
@Override
public boolean isStale() {
getterCalled();
return masterList.isStale();
}
@Override
public Iterator<E> iterator() {
getterCalled();
return new Iterator<E>() {
Iterator<T> it = masterList.iterator();
@Override
public boolean hasNext() {
getterCalled();
return it.hasNext();
}
@Override
public E next() {
getterCalled();
T masterElement = it.next();
return cache.get(masterElement);
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
}
@Override
public E move(int oldIndex, int newIndex) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object o) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public Object[] toArray() {
getterCalled();
Object[] masterElements = masterList.toArray();
Object[] result = new Object[masterElements.length];
for (int i = 0; i < result.length; i++) {
result[i] = cache.get(masterElements[i]);
}
return result;
}
@Override
@SuppressWarnings("unchecked")
public <U> U[] toArray(U[] a) {
getterCalled();
Object[] masterElements = masterList.toArray();
if (a.length < masterElements.length)
a = (U[]) Array.newInstance(a.getClass().getComponentType(), masterElements.length);
for (int i = 0; i < masterElements.length; i++) {
a[i] = (U) cache.get(masterElements[i]);
}
return a;
}
@Override
public void add(int index, Object o) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@Override
public ListIterator<E> listIterator() {
return listIterator(0);
}
@Override
public ListIterator<E> listIterator(final int index) {
getterCalled();
return new ListIterator<E>() {
ListIterator<T> it = masterList.listIterator(index);
T lastMasterElement;
E lastElement;
boolean haveIterated = false;
@Override
public void add(Object arg0) {
throw new UnsupportedOperationException();
}
@Override
public boolean hasNext() {
getterCalled();
return it.hasNext();
}
@Override
public boolean hasPrevious() {
getterCalled();
return it.hasPrevious();
}
@Override
public E next() {
getterCalled();
lastMasterElement = it.next();
lastElement = cache.get(lastMasterElement);
haveIterated = true;
return lastElement;
}
@Override
public int nextIndex() {
getterCalled();
return it.nextIndex();
}
@Override
public E previous() {
getterCalled();
lastMasterElement = it.previous();
lastElement = cache.get(lastMasterElement);
haveIterated = true;
return lastElement;
}
@Override
public int previousIndex() {
getterCalled();
return it.previousIndex();
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
@Override
public void set(E o) {
checkRealm();
if (!haveIterated)
throw new IllegalStateException();
cache.put(lastMasterElement, o);
lastElement = o;
}
};
}
private int[] indicesOf(Object masterElement) {
List<Integer> indices = new ArrayList<>();
for (ListIterator<T> it = masterList.listIterator(); it.hasNext();) {
if (masterElement == it.next())
indices.add(Integer.valueOf(it.previousIndex()));
}
int[] result = new int[indices.size()];
for (int i = 0; i < result.length; i++) {
result[i] = indices.get(i).intValue();
}
return result;
}
private void fireListChange(int[] indices, E oldValue, E newValue) {
List<ListDiffEntry<E>> differences = new ArrayList<>(indices.length * 2);
for (int index : indices) {
differences.add(Diffs.createListDiffEntry(index, false, oldValue));
differences.add(Diffs.createListDiffEntry(index, true, newValue));
}
fireListChange(Diffs.createListDiff(differences));
}
@Override
public E remove(int index) {
throw new UnsupportedOperationException();
}
@Override
public E set(int index, E o) {
checkRealm();
T masterElement = masterList.get(index);
return cache.put(masterElement, o);
}
@Override
public Object getObserved() {
return masterList;
}
@Override
public DelegatingValueProperty<S, E> getProperty() {
return detailProperty;
}
@Override
public Object getElementType() {
return detailProperty.getValueType();
}
@Override
public synchronized void dispose() {
if (masterList != null) {
masterList.removeListChangeListener(masterListener);
masterList.removeStaleListener(staleListener);
masterList = null;
}
if (cache != null) {
cache.dispose();
cache = null;
}
masterListener = null;
detailProperty = null;
super.dispose();
}
}