| /******************************************************************************* |
| * Copyright (c) 2006, 2017 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.internal.cheatsheets.composite.model; |
| |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.Set; |
| |
| import org.eclipse.ui.internal.provisional.cheatsheets.ICompositeCheatSheetTask; |
| |
| public class BlockedTaskFinder { |
| |
| private Set<ICompositeCheatSheetTask> stateChangedTasks; |
| private Set<ICompositeCheatSheetTask> impactedTasks; |
| /** |
| * Find which tasks have either become blocked or unblocked so that they |
| * can be added to the list of change events. |
| * @param stateChangedTasks The set of tasks which has changed |
| * @return The set of tasks which have become blocked or unblocked by the |
| * change of state and were not in the original set. The algorithm will sometimes add tasks to |
| * the result set which were not actually impacted but this is not a major problem |
| * since it only means that extra events get sent to the explorer. For updates other |
| * than resets the number of extra events is very low. |
| * |
| * This takes several steps. |
| * <li> If a group is completed, skipped or reset add any non-started children. |
| * <li> Determine all successors of tasks whose state has changed that are not in the change set |
| * <li> Add the successor and its children to the list if not started |
| */ |
| |
| public Set<ICompositeCheatSheetTask> findBlockedTaskChanges(Set<ICompositeCheatSheetTask> stateChangedTasks) { |
| this.stateChangedTasks = stateChangedTasks; |
| impactedTasks = new HashSet<>(); |
| visitChangedTasks(); |
| findSuccesors(); |
| return impactedTasks; |
| } |
| |
| private void visitChangedTasks() { |
| for (Iterator<ICompositeCheatSheetTask> iter = stateChangedTasks.iterator(); iter.hasNext();) { |
| final ICompositeCheatSheetTask nextTask = iter.next(); |
| if (nextTask.getState() != ICompositeCheatSheetTask.IN_PROGRESS) { |
| findUnstartedChildren(nextTask); |
| } |
| } |
| } |
| |
| /* |
| * Look for children which we have not seen elsewhere and if they are not started |
| * add them to the list of impacted tasks. |
| */ |
| private void findUnstartedChildren(ICompositeCheatSheetTask task) { |
| ICompositeCheatSheetTask[] children = task.getSubtasks(); |
| for (int i = 0; i < children.length; i++) { |
| ICompositeCheatSheetTask nextChild = children[i]; |
| // Ignore if this task has been seen before |
| if ((!stateChangedTasks.contains(nextChild)) && !impactedTasks.contains(nextChild)) { |
| if (nextChild.getState() == ICompositeCheatSheetTask.NOT_STARTED) { |
| impactedTasks.add(nextChild); |
| } |
| findUnstartedChildren(nextChild); |
| } |
| } |
| } |
| |
| private void findSuccesors() { |
| for (Iterator<ICompositeCheatSheetTask> iter = stateChangedTasks.iterator(); iter.hasNext();) { |
| final AbstractTask nextTask = (AbstractTask)iter.next(); |
| ICompositeCheatSheetTask[] successors = nextTask.getSuccessorTasks(); |
| for (int i = 0; i < successors.length; i++) { |
| ICompositeCheatSheetTask nextSuccessor = successors[i]; |
| if (nextSuccessor.getState() == ICompositeCheatSheetTask.NOT_STARTED) { |
| impactedTasks.add(nextSuccessor); |
| } |
| findUnstartedChildren(nextSuccessor); |
| } |
| } |
| } |
| |
| } |