org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/viewers/model/ChildrenCountUpdate.java - gerrit/platform/eclipse.platform.debug - Git at Google

 /*******************************************************************************
  * Copyright (c) 2006, 2018 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * 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(() -> {
 							if (!getContentProvider().isDisposed() && !isCanceled()) {
 								performUpdate();
 							}
 						});
      		    	}
      		    };
 				execInDisplayThread(() -> 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<>(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();
     }
 }
	/*******************************************************************************
	* Copyright (c) 2006, 2018 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* 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(() -> {
	if (!getContentProvider().isDisposed() && !isCanceled()) {
	performUpdate();
	}
	});
	}
	};
	execInDisplayThread(() -> 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<>(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();
	}
	}