/*******************************************************************************
* Copyright (c) 2006, 2013 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
* Wind River Systems - Fix for viewer state save/restore [188704]
* Pawel Piech (Wind River) - added support for a virtual tree model viewer (Bug 242489)
*******************************************************************************/
package org.eclipse.debug.internal.ui.viewers.model;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.debug.internal.ui.DebugUIPlugin;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IChildrenCountUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IElementContentProvider;
import org.eclipse.jface.viewers.TreePath;
/**
* @since 3.3
*/
class ChildrenCountUpdate extends ViewerUpdateMonitor implements IChildrenCountUpdate {
/**
* Child count result.
*/
private int fCount = 0;
/**
* Other child count updates for the same content provider. Coalesced requests are
* batched together into an array.
*/
private List<ViewerUpdateMonitor> fBatchedRequests = null;
/**
* Flag whether filtering is enabled in viewer. If filtering is enabled, then a
* children update is performed on child elements to filter them as part of the
* child count calculation.
*/
private boolean fShouldFilter = false;
/**
* Children indexes which are currently filtered. When updating child count, also need
* to verify that currently filtered children are still filtered.
*/
private int[] fFilteredChildren = null;
/**
* Children update used to filter children.
*/
private ChildrenUpdate fChildrenUpdate;
/**
* Constructor
* @param provider the content provider to use for the update
* @param viewerInput the current input
* @param elementPath the path of the element to update
* @param element the element to update
* @param elementContentProvider the content provider for the element
*/
public ChildrenCountUpdate(TreeModelContentProvider provider, Object viewerInput, TreePath elementPath, Object element, IElementContentProvider elementContentProvider) {
super(provider, viewerInput, elementPath, element, elementContentProvider, provider.getPresentationContext());
fShouldFilter = provider.areTreeModelViewerFiltersApplicable(element);
fFilteredChildren = provider.getFilteredChildren(elementPath);
}
@Override
public synchronized void cancel() {
if (fChildrenUpdate != null) {
fChildrenUpdate.cancel();
}
super.cancel();
}
@Override
protected synchronized void scheduleViewerUpdate() {
// If filtering is enabled perform child update on all children in order to update
// viewer filters.
if (fShouldFilter || fFilteredChildren != null) {
if (fChildrenUpdate == null) {
int startIdx;
int count;
if (fShouldFilter) {
startIdx = 0;
count = getCount();
} else {
startIdx = fFilteredChildren[0];
int endIdx = fFilteredChildren[fFilteredChildren.length - 1];
count = endIdx - startIdx + 1;
}
fChildrenUpdate = new ChildrenUpdate(getContentProvider(), getViewerInput(), getElementPath(), getElement(), startIdx, count, getElementContentProvider()) {
@Override
protected void performUpdate() {
performUpdate(true);
ChildrenCountUpdate.super.scheduleViewerUpdate();
}
@Override
protected void scheduleViewerUpdate() {
execInDisplayThread(new Runnable() {
@Override
public void run() {
if (!getContentProvider().isDisposed() && !isCanceled()) {
performUpdate();
}
}
});
}
};
execInDisplayThread(new Runnable() {
@Override
public void run() {
fChildrenUpdate.startRequest();
}
});
return;
}
} else {
super.scheduleViewerUpdate();
}
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.ui.viewers.model.provisional.viewers.ViewerUpdateMonitor#performUpdate()
*/
@Override
protected void performUpdate() {
int viewCount = fCount;
TreePath elementPath = getElementPath();
if (viewCount == 0) {
getContentProvider().clearFilters(elementPath);
} else {
getContentProvider().setModelChildCount(elementPath, fCount);
viewCount = getContentProvider().modelToViewChildCount(elementPath, fCount);
}
if (DebugUIPlugin.DEBUG_CONTENT_PROVIDER && DebugUIPlugin.DEBUG_TEST_PRESENTATION_ID(getPresentationContext())) {
DebugUIPlugin.trace("setChildCount(" + getElement() + ", modelCount: " + fCount + " viewCount: " + viewCount + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
}
// Special case for element 0 in a set of filtered elements:
// Child 0 is automatically updated by the tree at the same time that the child count is requested. Therefore,
// If this child count update filtered out this element, it needs to be updated again.
if (fShouldFilter && getContentProvider().isFiltered(elementPath, 0)) {
getContentProvider().updateElement(elementPath, 0);
}
getContentProvider().getViewer().setChildCount(elementPath, viewCount);
getContentProvider().getStateTracker().restorePendingStateOnUpdate(getElementPath(), -1, true, true, false);
}
@Override
public void setChildCount(int numChildren) {
fCount = numChildren;
}
@Override
public String toString() {
StringBuffer buf = new StringBuffer();
buf.append("IChildrenCountUpdate: "); //$NON-NLS-1$
buf.append(getElement());
return buf.toString();
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.ui.viewers.model.ViewerUpdateMonitor#coalesce(org.eclipse.debug.internal.ui.viewers.model.ViewerUpdateMonitor)
*/
@Override
boolean coalesce(ViewerUpdateMonitor request) {
if (request instanceof ChildrenCountUpdate) {
if (getElementPath().equals(request.getElementPath())) {
// duplicate request
return true;
} else if (getElementContentProvider().equals(request.getElementContentProvider())) {
if (fBatchedRequests == null) {
fBatchedRequests = new ArrayList<ViewerUpdateMonitor>(4);
fBatchedRequests.add(this);
}
fBatchedRequests.add(request);
return true;
}
}
return false;
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.ui.viewers.model.ViewerUpdateMonitor#startRequest()
*/
@Override
void startRequest() {
if (fBatchedRequests == null) {
getElementContentProvider().update(new IChildrenCountUpdate[]{this});
} else {
IChildrenCountUpdate[] updates = fBatchedRequests.toArray(new IChildrenCountUpdate[fBatchedRequests.size()]);
// notify that the other updates have also started to ensure correct sequence
// of model updates - **** start at index 1 since the first (0) update has
// already notified the content provider that it has started.
for (int i = 1; i < updates.length; i++) {
getContentProvider().updateStarted((ViewerUpdateMonitor) updates[i]);
}
getElementContentProvider().update(updates);
}
}
@Override
boolean containsUpdate(TreePath path) {
if (getElementPath().equals(path)) {
return true;
} else if (fBatchedRequests != null) {
for (int i = 0; i < fBatchedRequests.size(); i++) {
if (fBatchedRequests.get(i).getElementPath().equals(path)) {
return true;
}
}
}
return false;
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.ui.viewers.model.ViewerUpdateMonitor#getPriority()
*/
@Override
int getPriority() {
return 2;
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.ui.viewers.model.ViewerUpdateMonitor#getSchedulingPath()
*/
@Override
TreePath getSchedulingPath() {
TreePath path = getElementPath();
if (path.getSegmentCount() > 0) {
return path.getParentPath();
}
return path;
}
int getCount() {
return fCount;
}
@Override
protected boolean doEquals(ViewerUpdateMonitor update) {
return
update instanceof ChildrenCountUpdate &&
getViewerInput().equals(update.getViewerInput()) &&
getElementPath().equals(update.getElementPath());
}
@Override
protected int doHashCode() {
return getClass().hashCode() + getViewerInput().hashCode() + getElementPath().hashCode();
}
}