Java tutorial
/* * Copyright (c) 2012, the Dart project authors. * * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at * * http://www.eclipse.org/legal/epl-v10.html * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. */ package com.google.dart.tools.ui.internal.search; import com.google.dart.tools.core.model.CompilationUnit; import com.google.dart.tools.core.model.DartElement; import com.google.dart.tools.core.model.Type; import com.google.dart.tools.search.ui.text.AbstractTextSearchResult; import org.eclipse.core.resources.IResource; import org.eclipse.core.runtime.IAdaptable; import org.eclipse.jface.viewers.AbstractTreeViewer; import org.eclipse.jface.viewers.ITreeContentProvider; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.Map; import java.util.Set; /** * Tree-based Dart content provider. */ public class LevelTreeContentProvider extends DartSearchContentProvider implements ITreeContentProvider { static class FastDartElementProvider extends DartElementSearchContentProvider { @Override public Object getParent(Object element) { Object parent = internalGetParent(element); if (parent == null && element instanceof IAdaptable) { IAdaptable adaptable = (IAdaptable) element; Object dartElement = adaptable.getAdapter(DartElement.class); if (dartElement != null) { parent = internalGetParent(dartElement); } else { Object resource = adaptable.getAdapter(IResource.class); if (resource != null) { parent = internalGetParent(resource); } } } return parent; } } public static final int LEVEL_FILE = 2; public static final int LEVEL_PACKAGE = 3; public static final int LEVEL_PROJECT = 4; public static final int LEVEL_TYPE = 1; private static final int[][] DART_ELEMENT_TYPES = { { DartElement.TYPE }, /*{DartElement.LIBRARY}, */ { DartElement.DART_PROJECT /*, DartElement.LIBRARY */ }, { DartElement.DART_MODEL } }; private static final int MAX_LEVEL = DART_ELEMENT_TYPES.length - 1; private static final int[][] RESOURCE_TYPES = { {}, { IResource.FILE }, { IResource.FOLDER }, { IResource.PROJECT }, { IResource.ROOT } }; private Map<Object, Set<Object>> childrenMap; private DartElementSearchContentProvider contentProvider; private int currentLevel; public LevelTreeContentProvider(DartSearchResultPage page, int level) { super(page); currentLevel = level; contentProvider = new FastDartElementProvider(); } @Override public void clear() { initialize(getSearchResult()); getPage().getViewer().refresh(); } @Override public synchronized void elementsChanged(Object[] updatedElements) { if (getSearchResult() == null) { return; } AbstractTreeViewer viewer = (AbstractTreeViewer) getPage().getViewer(); Set<Object> toRemove = new HashSet<Object>(); Set<Object> toUpdate = new HashSet<Object>(); Map<Object, Set<Object>> toAdd = new HashMap<Object, Set<Object>>(); for (int i = 0; i < updatedElements.length; i++) { if (getPage().getDisplayedMatchCount(updatedElements[i]) > 0) { insert(toAdd, toUpdate, updatedElements[i]); } else { remove(toRemove, toUpdate, updatedElements[i]); } } viewer.remove(toRemove.toArray()); for (Iterator<Object> iter = toAdd.keySet().iterator(); iter.hasNext();) { Object parent = iter.next(); Set<Object> children = toAdd.get(parent); viewer.add(parent, children.toArray()); } for (Iterator<Object> elementsToUpdate = toUpdate.iterator(); elementsToUpdate.hasNext();) { viewer.refresh(elementsToUpdate.next()); } } @Override public Object[] getChildren(Object parentElement) { Set<Object> children = childrenMap.get(parentElement); if (children == null) { return EMPTY_ARRAY; } int limit = getPage().getElementLimit().intValue(); if (limit != -1 && limit < children.size()) { Object[] limitedArray = new Object[limit]; Iterator<Object> iterator = children.iterator(); for (int i = 0; i < limit; i++) { limitedArray[i] = iterator.next(); } return limitedArray; } return children.toArray(); } @Override public Object[] getElements(Object inputElement) { return getChildren(inputElement); } @Override public Object getParent(Object child) { Object possibleParent = internalGetParent(child); if (possibleParent instanceof DartElement) { DartElement dartElement = (DartElement) possibleParent; for (int j = currentLevel; j < MAX_LEVEL + 1; j++) { for (int i = 0; i < DART_ELEMENT_TYPES[j].length; i++) { if (dartElement.getElementType() == DART_ELEMENT_TYPES[j][i]) { return null; } } } } else if (possibleParent instanceof IResource) { IResource resource = (IResource) possibleParent; for (int j = currentLevel; j < MAX_LEVEL + 1; j++) { for (int i = 0; i < RESOURCE_TYPES[j].length; i++) { if (resource.getType() == RESOURCE_TYPES[j][i]) { return null; } } } } if (currentLevel != LEVEL_FILE && child instanceof Type) { Type type = (Type) child; if (possibleParent instanceof CompilationUnit) { possibleParent = type.getLibrary(); } } return possibleParent; } @Override public boolean hasChildren(Object element) { Set<Object> children = childrenMap.get(element); return children != null && !children.isEmpty(); } public void setLevel(int level) { currentLevel = level; initialize(getSearchResult()); getPage().getViewer().refresh(); } @Override protected synchronized void initialize(AbstractTextSearchResult result) { super.initialize(result); childrenMap = new HashMap<Object, Set<Object>>(); if (result != null) { Object[] elements = result.getElements(); for (int i = 0; i < elements.length; i++) { if (getPage().getDisplayedMatchCount(elements[i]) > 0) { insert(null, null, elements[i]); } } } } protected void insert(Map<Object, Set<Object>> toAdd, Set<Object> toUpdate, Object child) { Object parent = getParent(child); while (parent != null) { if (insertChild(parent, child)) { if (toAdd != null) { insertInto(parent, child, toAdd); } } else { if (toUpdate != null) { toUpdate.add(parent); } return; } child = parent; parent = getParent(child); } if (insertChild(getSearchResult(), child)) { if (toAdd != null) { insertInto(getSearchResult(), child, toAdd); } } } protected void remove(Set<Object> toRemove, Set<Object> toUpdate, Object element) { // precondition here: fResult.getMatchCount(child) <= 0 if (hasChildren(element)) { if (toUpdate != null) { toUpdate.add(element); } } else { if (getPage().getDisplayedMatchCount(element) == 0) { childrenMap.remove(element); Object parent = getParent(element); if (parent != null) { if (removeFromSiblings(element, parent)) { remove(toRemove, toUpdate, parent); } } else { if (removeFromSiblings(element, getSearchResult())) { if (toRemove != null) { toRemove.add(element); } } } } else { if (toUpdate != null) { toUpdate.add(element); } } } } private boolean insertChild(Object parent, Object child) { return insertInto(parent, child, childrenMap); } private boolean insertInto(Object parent, Object child, Map<Object, Set<Object>> map) { Set<Object> children = map.get(parent); if (children == null) { children = new HashSet<Object>(); map.put(parent, children); } return children.add(child); } private Object internalGetParent(Object child) { return contentProvider.getParent(child); } /** * Tries to remove the given element from the list of stored siblings. * * @param element potential child * @param parent potential parent * @return returns true if it really was a remove (i.e. element was a child of parent). */ private boolean removeFromSiblings(Object element, Object parent) { Set<Object> siblings = childrenMap.get(parent); if (siblings != null) { return siblings.remove(element); } else { return false; } } }