| /******************************************************************************* |
| * Copyright (c) 2000, 2016 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 |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.ui.navigator; |
| |
| |
| import org.eclipse.jface.viewers.IStructuredContentProvider; |
| import org.eclipse.jface.viewers.ITreeContentProvider; |
| import org.eclipse.jface.viewers.StructuredViewer; |
| import org.eclipse.jface.viewers.Viewer; |
| import org.eclipse.jface.viewers.ViewerFilter; |
| |
| import org.eclipse.ui.navigator.CommonViewer; |
| import org.eclipse.ui.navigator.IExtensionStateModel; |
| import org.eclipse.ui.navigator.INavigatorContentService; |
| |
| import org.eclipse.jdt.core.IPackageFragment; |
| import org.eclipse.jdt.core.JavaModelException; |
| |
| /** |
| * |
| * This filter is only applicable to instances of the Common Navigator. |
| * |
| * This filter will not allow essential elements to be blocked. |
| */ |
| public abstract class NonEssentialElementsFilter extends ViewerFilter { |
| |
| private static final String JAVA_EXTENSION_ID = "org.eclipse.jdt.java.ui.javaContent"; //$NON-NLS-1$ |
| |
| private boolean isStateModelInitialized = false; |
| private IExtensionStateModel fStateModel = null; |
| |
| private INavigatorContentService fContentService; |
| |
| private ViewerFilter fDelegateFilter; |
| |
| /** |
| * |
| * @param delegateFilter A filter to delegate to, can be null |
| */ |
| protected NonEssentialElementsFilter(ViewerFilter delegateFilter) { |
| fDelegateFilter = delegateFilter; |
| } |
| |
| @Override |
| public boolean select(Viewer viewer, Object parent, Object element) { |
| if (!isStateModelInitialized) { |
| initStateModel(viewer); |
| } |
| if (fContentService == null || fStateModel == null) { |
| return true; |
| } else if (element instanceof IPackageFragment) { |
| if (isApplicable() && viewer instanceof StructuredViewer) { |
| boolean isHierarchicalLayout= !fStateModel.getBooleanProperty(IExtensionStateConstants.Values.IS_LAYOUT_FLAT); |
| try { |
| IPackageFragment fragment = (IPackageFragment) element; |
| if (isHierarchicalLayout && !fragment.isDefaultPackage() && fragment.hasSubpackages()) { |
| return hasFilteredChildren((StructuredViewer) viewer, fragment); |
| } |
| } catch (JavaModelException e) { |
| return false; |
| } |
| } |
| } |
| return doSelect(viewer, parent, element); |
| } |
| |
| protected boolean hasFilteredChildren(StructuredViewer viewer, Object element) { |
| Object[] children= getRawChildren(viewer, element); |
| ViewerFilter[] filters= viewer.getFilters(); |
| for (int i= 0; i < filters.length; i++) { |
| boolean hasSelectedChildren= false; |
| // next lines are identical to ViewerFilter.filter(Viewer, Object, Object[]), but exit early when first child is found |
| int size = children.length; |
| for (int j = 0; j < size; ++j) { |
| if (filters[i].select(viewer, element, children[j])) { |
| hasSelectedChildren = true; |
| break; |
| } |
| } |
| if (!hasSelectedChildren) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| private Object[] getRawChildren(StructuredViewer viewer, Object element) { |
| IStructuredContentProvider provider = (IStructuredContentProvider) viewer.getContentProvider(); |
| if (provider instanceof ITreeContentProvider) { |
| return ((ITreeContentProvider)provider).getChildren(element); |
| } |
| return provider.getElements(element); |
| } |
| |
| protected boolean doSelect(Viewer viewer, Object parent, Object element) { |
| return fDelegateFilter != null ? fDelegateFilter.select(viewer, parent, element) : true; |
| } |
| |
| protected boolean isApplicable() { |
| return fContentService != null && fContentService.isVisible(JAVA_EXTENSION_ID) && fContentService.isActive(JAVA_EXTENSION_ID); |
| } |
| |
| private synchronized void initStateModel(Viewer viewer) { |
| if (!isStateModelInitialized) { |
| if (viewer instanceof CommonViewer) { |
| |
| CommonViewer commonViewer = (CommonViewer) viewer; |
| fContentService = commonViewer.getNavigatorContentService(); |
| fStateModel = fContentService.findStateModel(JAVA_EXTENSION_ID); |
| |
| isStateModelInitialized = true; |
| } |
| } |
| } |
| } |