/*******************************************************************************
* Copyright (c) 2005, 2015 IBM Corporation 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:
* IBM Corporation - initial API and implementation
* Brad Reynolds - bugs 164653, 167204
* Gautam Saggar - bug 169529
* Brad Reynolds - bug 147515
* Sebastian Fuchs <spacehorst@gmail.com> - bug 243848
* Matthew Hall - bugs 208858, 213145, 243848
* Ovidio Mallo - bug 332367
* Stefan Xenos <sxenos@gmail.com> - Bug 335792
*******************************************************************************/
package org.eclipse.core.databinding.observable.list;
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.Realm;
/**
* Mutable observable list backed by an ArrayList.
*
* <p>
* This class is thread safe. All state accessing methods must be invoked from
* the {@link Realm#isCurrent() current realm}. Methods for adding and removing
* listeners may be invoked from any thread.
* </p>
*
* @param <E>
* the type of the elements in this list
*
* @since 1.0
*/
public class WritableList<E> extends ObservableList<E> {
/**
* Creates an empty writable list in the default realm with a
* <code>null</code> element type.
*
*/
public WritableList() {
this(Realm.getDefault());
}
/**
* Creates an empty writable list with a <code>null</code> element type.
*
* @param realm
* the observable's realm
*/
public WritableList(Realm realm) {
this(realm, new ArrayList<E>(), null);
}
/**
* Constructs a new instance with the default realm. Note that for backwards
* compatibility reasons, the contents of the created WritableList will
* change with the contents of the given list. If this is not desired,
* {@link #WritableList(Collection, Object)} should be used by casting the
* first argument to {@link Collection}.
*
* @param toWrap
* The java.util.List to wrap
* @param elementType
* can be <code>null</code>
*/
public WritableList(List<E> toWrap, Object elementType) {
this(Realm.getDefault(), toWrap, elementType);
}
/**
* Constructs a new instance in the default realm containing the elements of
* the given collection. Changes to the given collection after calling this
* method do not affect the contents of the created WritableList.
*
* @param collection
* the collection to copy
* @param elementType
* can be <code>null</code>
* @since 1.2
*/
public WritableList(Collection<E> collection, Object elementType) {
this(Realm.getDefault(), new ArrayList<E>(collection), elementType);
}
/**
* Creates a writable list containing elements of the given type, wrapping
* an existing client-supplied list. Note that for backwards compatibility
* reasons, the contents of the created WritableList will change with the
* contents of the given list. If this is not desired,
* {@link #WritableList(Realm, Collection, Object)} should be used by
* casting the second argument to {@link Collection}.
*
* @param realm
* the observable's realm
* @param toWrap
* The java.util.List to wrap
* @param elementType
* can be <code>null</code>
*/
public WritableList(Realm realm, List<E> toWrap, Object elementType) {
super(realm, toWrap, elementType);
}
/**
* Constructs a new instance in the default realm containing the elements of
* the given collection. Changes to the given collection after calling this
* method do not affect the contents of the created WritableList.
*
* @param realm
* the observable's realm
* @param collection
* the collection to copy
* @param elementType
* can be <code>null</code>
* @since 1.2
*/
public WritableList(Realm realm, Collection<E> collection,
Object elementType) {
super(realm, new ArrayList<E>(collection), elementType);
}
@Override
public E set(int index, E element) {
checkRealm();
E oldElement = wrappedList.set(index, element);
fireListChange(Diffs.createListDiff(
Diffs.createListDiffEntry(index, false, oldElement),
Diffs.createListDiffEntry(index, true, element)));
return oldElement;
}
/**
* @since 1.1
*/
@Override
public E move(int oldIndex, int newIndex) {
checkRealm();
int size = wrappedList.size();
if (oldIndex < 0 || oldIndex >= size)
throw new IndexOutOfBoundsException(
"oldIndex: " + oldIndex + ", size:" + size); //$NON-NLS-1$ //$NON-NLS-2$
if (newIndex < 0 || newIndex >= size)
throw new IndexOutOfBoundsException(
"newIndex: " + newIndex + ", size:" + size); //$NON-NLS-1$ //$NON-NLS-2$
if (oldIndex == newIndex)
return wrappedList.get(oldIndex);
E element = wrappedList.remove(oldIndex);
wrappedList.add(newIndex, element);
fireListChange(Diffs.createListDiff(
Diffs.createListDiffEntry(oldIndex, false, element),
Diffs.createListDiffEntry(newIndex, true, element)));
return element;
}
@Override
public E remove(int index) {
checkRealm();
E oldElement = wrappedList.remove(index);
fireListChange(Diffs.createListDiff(Diffs.createListDiffEntry(index,
false, oldElement)));
return oldElement;
}
@Override
public boolean add(E element) {
checkRealm();
boolean added = wrappedList.add(element);
if (added) {
fireListChange(Diffs.createListDiff(Diffs.createListDiffEntry(
wrappedList.size() - 1, true, element)));
}
return added;
}
@Override
public void add(int index, E element) {
checkRealm();
wrappedList.add(index, element);
fireListChange(Diffs.createListDiff(Diffs.createListDiffEntry(index,
true, element)));
}
@Override
public boolean addAll(Collection<? extends E> c) {
checkRealm();
List<ListDiffEntry<E>> entries = new ArrayList<ListDiffEntry<E>>(
c.size());
int addIndex = wrappedList.size();
for (E element : c) {
entries.add(Diffs.createListDiffEntry(addIndex++, true, element));
}
boolean added = wrappedList.addAll(c);
fireListChange(Diffs.createListDiff(entries));
return added;
}
@Override
public boolean addAll(int index, Collection<? extends E> c) {
checkRealm();
List<ListDiffEntry<E>> entries = new ArrayList<ListDiffEntry<E>>(
c.size());
int addIndex = index;
for (E element : c) {
entries.add(Diffs.createListDiffEntry(addIndex++, true, element));
}
boolean added = wrappedList.addAll(index, c);
fireListChange(Diffs.createListDiff(entries));
return added;
}
@Override
public boolean remove(Object o) {
checkRealm();
int index = wrappedList.indexOf(o);
if (index == -1) {
return false;
}
// Fetch it back so we can get it typed in a safe manner
E typedO = wrappedList.get(index);
wrappedList.remove(index);
fireListChange(Diffs.createListDiff(Diffs.createListDiffEntry(index,
false, typedO)));
return true;
}
@Override
public boolean removeAll(Collection<?> c) {
checkRealm();
List<ListDiffEntry<E>> entries = new ArrayList<ListDiffEntry<E>>();
for (Object element : c) {
int removeIndex = wrappedList.indexOf(element);
if (removeIndex != -1) {
E removedElement = wrappedList.get(removeIndex);
wrappedList.remove(removeIndex);
entries.add(Diffs.createListDiffEntry(removeIndex, false,
removedElement));
}
}
if (entries.size() > 0)
fireListChange(Diffs.createListDiff(entries));
return entries.size() > 0;
}
@Override
public boolean retainAll(Collection<?> c) {
checkRealm();
List<ListDiffEntry<E>> entries = new ArrayList<ListDiffEntry<E>>();
int removeIndex = 0;
for (Iterator<E> it = wrappedList.iterator(); it.hasNext();) {
E element = it.next();
if (!c.contains(element)) {
entries.add(Diffs.createListDiffEntry(removeIndex, false,
element));
it.remove();
} else {
// only increment if we haven't removed the current element
removeIndex++;
}
}
if (entries.size() > 0)
fireListChange(Diffs.createListDiff(entries));
return entries.size() > 0;
}
@Override
public void clear() {
checkRealm();
// We remove the elements from back to front which is typically much
// faster on common list implementations like ArrayList.
List<ListDiffEntry<E>> entries = new ArrayList<ListDiffEntry<E>>(
wrappedList.size());
for (ListIterator<E> it = wrappedList.listIterator(wrappedList.size()); it
.hasPrevious();) {
int elementIndex = it.previousIndex();
E element = it.previous();
entries.add(Diffs.createListDiffEntry(elementIndex, false, element));
}
wrappedList.clear();
fireListChange(Diffs.createListDiff(entries));
}
/**
* @param elementType
* can be <code>null</code>
* @return new list with the default realm.
*/
public static <T> WritableList<T> withElementType(Object elementType) {
return new WritableList<T>(Realm.getDefault(), new ArrayList<T>(), elementType);
}
}