/*******************************************************************************
* Copyright (c) 2000, 2008 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
*******************************************************************************/
package org.eclipse.ui.model;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceChangeEvent;
import org.eclipse.core.resources.IResourceChangeListener;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.IWorkspace;
import org.eclipse.jface.viewers.AbstractTreeViewer;
import org.eclipse.jface.viewers.StructuredViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.widgets.Control;
/**
* Tree content provider for resource objects that can be adapted to the
* interface {@link org.eclipse.ui.model.IWorkbenchAdapter IWorkbenchAdapter}.
* This provider will listen for resource changes within the workspace and
* update the viewer as necessary.
* <p>
* This class may be instantiated, or subclassed by clients.
* </p>
*/
public class WorkbenchContentProvider extends BaseWorkbenchContentProvider
implements IResourceChangeListener {
private Viewer viewer;
/**
* Creates the resource content provider.
*/
public WorkbenchContentProvider() {
super();
}
/*
* (non-Javadoc) Method declared on IContentProvider.
*/
public void dispose() {
if (viewer != null) {
IWorkspace workspace = null;
Object obj = viewer.getInput();
if (obj instanceof IWorkspace) {
workspace = (IWorkspace) obj;
} else if (obj instanceof IContainer) {
workspace = ((IContainer) obj).getWorkspace();
}
if (workspace != null) {
workspace.removeResourceChangeListener(this);
}
}
super.dispose();
}
/*
* (non-Javadoc) Method declared on IContentProvider.
*/
public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
super.inputChanged(viewer, oldInput, newInput);
this.viewer = viewer;
IWorkspace oldWorkspace = null;
IWorkspace newWorkspace = null;
if (oldInput instanceof IWorkspace) {
oldWorkspace = (IWorkspace) oldInput;
} else if (oldInput instanceof IContainer) {
oldWorkspace = ((IContainer) oldInput).getWorkspace();
}
if (newInput instanceof IWorkspace) {
newWorkspace = (IWorkspace) newInput;
} else if (newInput instanceof IContainer) {
newWorkspace = ((IContainer) newInput).getWorkspace();
}
if (oldWorkspace != newWorkspace) {
if (oldWorkspace != null) {
oldWorkspace.removeResourceChangeListener(this);
}
if (newWorkspace != null) {
newWorkspace.addResourceChangeListener(this,
IResourceChangeEvent.POST_CHANGE);
}
}
}
/*
* (non-Javadoc) Method declared on IResourceChangeListener.
*/
public final void resourceChanged(final IResourceChangeEvent event) {
processDelta(event.getDelta());
}
/**
* Process the resource delta.
*
* @param delta
*/
protected void processDelta(IResourceDelta delta) {
Control ctrl = viewer.getControl();
if (ctrl == null || ctrl.isDisposed()) {
return;
}
final Collection runnables = new ArrayList();
processDelta(delta, runnables);
if (runnables.isEmpty()) {
return;
}
//Are we in the UIThread? If so spin it until we are done
if (ctrl.getDisplay().getThread() == Thread.currentThread()) {
runUpdates(runnables);
} else {
ctrl.getDisplay().asyncExec(new Runnable(){
/* (non-Javadoc)
* @see java.lang.Runnable#run()
*/
public void run() {
//Abort if this happens after disposes
Control ctrl = viewer.getControl();
if (ctrl == null || ctrl.isDisposed()) {
return;
}
runUpdates(runnables);
}
});
}
}
/**
* Run all of the runnables that are the widget updates
* @param runnables
*/
private void runUpdates(Collection runnables) {
Iterator runnableIterator = runnables.iterator();
while(runnableIterator.hasNext()){
((Runnable)runnableIterator.next()).run();
}
}
/**
* Process a resource delta. Add any runnables
*/
private void processDelta(IResourceDelta delta, Collection runnables) {
//he widget may have been destroyed
// by the time this is run. Check for this and do nothing if so.
Control ctrl = viewer.getControl();
if (ctrl == null || ctrl.isDisposed()) {
return;
}
// Get the affected resource
final IResource resource = delta.getResource();
// If any children have changed type, just do a full refresh of this
// parent,
// since a simple update on such children won't work,
// and trying to map the change to a remove and add is too dicey.
// The case is: folder A renamed to existing file B, answering yes to
// overwrite B.
IResourceDelta[] affectedChildren = delta
.getAffectedChildren(IResourceDelta.CHANGED);
for (int i = 0; i < affectedChildren.length; i++) {
if ((affectedChildren[i].getFlags() & IResourceDelta.TYPE) != 0) {
runnables.add(getRefreshRunnable(resource));
return;
}
}
// Opening a project just affects icon, but we need to refresh when
// a project is closed because if child items have not yet been created
// in the tree we still need to update the item's children
int changeFlags = delta.getFlags();
if ((changeFlags & IResourceDelta.OPEN) != 0) {
if (resource.isAccessible()) {
runnables.add(getUpdateRunnable(resource));
} else {
runnables.add(getRefreshRunnable(resource));
return;
}
}
// Check the flags for changes the Navigator cares about.
// See ResourceLabelProvider for the aspects it cares about.
// Notice we don't care about F_CONTENT or F_MARKERS currently.
if ((changeFlags & (IResourceDelta.SYNC
| IResourceDelta.TYPE | IResourceDelta.DESCRIPTION)) != 0) {
runnables.add(getUpdateRunnable(resource));
}
// Replacing a resource may affect its label and its children
if ((changeFlags & IResourceDelta.REPLACED) != 0) {
runnables.add(getRefreshRunnable(resource));
return;
}
// Handle changed children .
for (int i = 0; i < affectedChildren.length; i++) {
processDelta(affectedChildren[i], runnables);
}
// @issue several problems here:
// - should process removals before additions, to avoid multiple equal
// elements in viewer
// - Kim: processing removals before additions was the indirect cause of
// 44081 and its varients
// - Nick: no delta should have an add and a remove on the same element,
// so processing adds first is probably OK
// - using setRedraw will cause extra flashiness
// - setRedraw is used even for simple changes
// - to avoid seeing a rename in two stages, should turn redraw on/off
// around combined removal and addition
// - Kim: done, and only in the case of a rename (both remove and add
// changes in one delta).
IResourceDelta[] addedChildren = delta
.getAffectedChildren(IResourceDelta.ADDED);
IResourceDelta[] removedChildren = delta
.getAffectedChildren(IResourceDelta.REMOVED);
if (addedChildren.length == 0 && removedChildren.length == 0) {
return;
}
final Object[] addedObjects;
final Object[] removedObjects;
// Process additions before removals as to not cause selection
// preservation prior to new objects being added
// Handle added children. Issue one update for all insertions.
int numMovedFrom = 0;
int numMovedTo = 0;
if (addedChildren.length > 0) {
addedObjects = new Object[addedChildren.length];
for (int i = 0; i < addedChildren.length; i++) {
addedObjects[i] = addedChildren[i].getResource();
if ((addedChildren[i].getFlags() & IResourceDelta.MOVED_FROM) != 0) {
++numMovedFrom;
}
}
} else {
addedObjects = new Object[0];
}
// Handle removed children. Issue one update for all removals.
if (removedChildren.length > 0) {
removedObjects = new Object[removedChildren.length];
for (int i = 0; i < removedChildren.length; i++) {
removedObjects[i] = removedChildren[i].getResource();
if ((removedChildren[i].getFlags() & IResourceDelta.MOVED_TO) != 0) {
++numMovedTo;
}
}
} else {
removedObjects = new Object[0];
}
// heuristic test for items moving within same folder (i.e. renames)
final boolean hasRename = numMovedFrom > 0 && numMovedTo > 0;
Runnable addAndRemove = new Runnable(){
public void run() {
if (viewer instanceof AbstractTreeViewer) {
AbstractTreeViewer treeViewer = (AbstractTreeViewer) viewer;
// Disable redraw until the operation is finished so we don't
// get a flash of both the new and old item (in the case of
// rename)
// Only do this if we're both adding and removing files (the
// rename case)
if (hasRename) {
treeViewer.getControl().setRedraw(false);
}
try {
if (addedObjects.length > 0) {
treeViewer.add(resource, addedObjects);
}
if (removedObjects.length > 0) {
treeViewer.remove(removedObjects);
}
}
finally {
if (hasRename) {
treeViewer.getControl().setRedraw(true);
}
}
} else {
((StructuredViewer) viewer).refresh(resource);
}
}
};
runnables.add(addAndRemove);
}
/**
* Return a runnable for refreshing a resource.
* @param resource
* @return Runnable
*/
private Runnable getRefreshRunnable(final IResource resource) {
return new Runnable(){
public void run() {
((StructuredViewer) viewer).refresh(resource);
}
};
}
/**
* Return a runnable for refreshing a resource.
* @param resource
* @return Runnable
*/
private Runnable getUpdateRunnable(final IResource resource) {
return new Runnable(){
public void run() {
((StructuredViewer) viewer).update(resource, null);
}
};
}
}