mapping/plugins/org.eclipse.intent.mapping.ide.ui/src/org/eclipse/intent/mapping/ide/ui/view/FilteredCheckboxTree.java

/*******************************************************************************
 * Copyright (c) 2016 Obeo.
 * 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:
 *    Obeo - initial API and implementation and/or initial documentation
 *    ...
 *******************************************************************************/
package org.eclipse.intent.mapping.ide.ui.view;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.intent.mapping.ide.ui.Activator;
import org.eclipse.jface.viewers.CheckboxTreeViewer;
import org.eclipse.jface.viewers.IContentProvider;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.dialogs.FilteredTree;
import org.eclipse.ui.dialogs.PatternFilter;

/**
 * A tree that filter and has check boxes.
 *
 * @author <a href="mailto:yvan.lussaud@obeo.fr">Yvan Lussaud</a>
 */
public class FilteredCheckboxTree extends FilteredTree {

	/**
	 * Constructor.
	 * 
	 * @param parent
	 *            the parent <code>Composite</code>
	 * @param treeStyle
	 *            the style bits for the <code>Tree</code>
	 * @param filter
	 *            the filter to be used
	 * @param useNewLook
	 *            <code>true</code> if the new 3.5 look should be used
	 */
	public FilteredCheckboxTree(Composite parent, int treeStyle, PatternFilter filter, boolean useNewLook) {
		super(parent, treeStyle, filter, useNewLook);
	}

	/**
	 * Custom tree viewer subclass that clears the caches in patternFilter on any change to the tree. See bug
	 * 187200.
	 * 
	 * @since 3.3
	 */
	class NotifyingTreeViewer extends CheckboxTreeViewer {

		/**
		 * Clear cache {@link Method}.
		 */
		private final Method clearCaches;

		/**
		 * A notifying tree with check boxes.
		 * 
		 * @param parent
		 *            the parent control
		 * @param style
		 *            the SWT style bits
		 */
		NotifyingTreeViewer(Composite parent, int style) {
			super(parent, style);
			Method method = null;
			try {
				method = PatternFilter.class.getDeclaredMethod("clearCaches");
				method.setAccessible(true);
			} catch (NoSuchMethodException e) {
				Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e
						.getMessage(), e));
			} catch (SecurityException e) {
				Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e
						.getMessage(), e));
			}
			clearCaches = method;
		}

		/**
		 * Clear the cache.
		 */
		private void clearCache() {
			try {
				clearCaches.invoke(getPatternFilter());
			} catch (IllegalAccessException e) {
				Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e
						.getMessage(), e));
			} catch (IllegalArgumentException e) {
				Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e
						.getMessage(), e));
			} catch (InvocationTargetException e) {
				Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e
						.getMessage(), e));
			}
		}

		@Override
		public void add(Object parentElementOrTreePath, Object childElement) {
			clearCache();
			super.add(parentElementOrTreePath, childElement);
		}

		@Override
		public void add(Object parentElementOrTreePath, Object[] childElements) {
			clearCache();
			super.add(parentElementOrTreePath, childElements);
		}

		@Override
		protected void inputChanged(Object input, Object oldInput) {
			clearCache();
			super.inputChanged(input, oldInput);
		}

		@Override
		public void insert(Object parentElementOrTreePath, Object element, int position) {
			clearCache();
			super.insert(parentElementOrTreePath, element, position);
		}

		@Override
		public void refresh() {
			clearCache();
			super.refresh();
		}

		@Override
		public void refresh(boolean updateLabels) {
			clearCache();
			super.refresh(updateLabels);
		}

		@Override
		public void refresh(Object element) {
			clearCache();
			super.refresh(element);
		}

		@Override
		public void refresh(Object element, boolean updateLabels) {
			clearCache();
			super.refresh(element, updateLabels);
		}

		@Override
		public void remove(Object elementsOrTreePaths) {
			clearCache();
			super.remove(elementsOrTreePaths);
		}

		@Override
		public void remove(Object parent, Object[] elements) {
			clearCache();
			super.remove(parent, elements);
		}

		@Override
		public void remove(Object[] elementsOrTreePaths) {
			clearCache();
			super.remove(elementsOrTreePaths);
		}

		@Override
		public void replace(Object parentElementOrTreePath, int index, Object element) {
			clearCache();
			super.replace(parentElementOrTreePath, index, element);
		}

		@Override
		public void setChildCount(Object elementOrTreePath, int count) {
			clearCache();
			super.setChildCount(elementOrTreePath, count);
		}

		@Override
		public void setContentProvider(IContentProvider provider) {
			clearCache();
			super.setContentProvider(provider);
		}

		@Override
		public void setHasChildren(Object elementOrTreePath, boolean hasChildren) {
			clearCache();
			super.setHasChildren(elementOrTreePath, hasChildren);
		}

	}

	@Override
	protected TreeViewer doCreateTreeViewer(Composite parent, int style) {
		return new NotifyingTreeViewer(parent, style);
	}

	@Override
	public CheckboxTreeViewer getViewer() {
		return (CheckboxTreeViewer)super.getViewer();
	}

}