core/plugins/org.eclipse.dltk.ui/src/org/eclipse/dltk/internal/ui/workingsets/RemoveWorkingSetElementAction.java

/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.ui.workingsets;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.dltk.ui.actions.SelectionDispatchAction;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ITreeSelection;
import org.eclipse.jface.viewers.TreePath;
import org.eclipse.ui.IWorkbenchSite;
import org.eclipse.ui.IWorkingSet;

public class RemoveWorkingSetElementAction extends SelectionDispatchAction {

	public RemoveWorkingSetElementAction(IWorkbenchSite site) {
		super(site);
		setText(WorkingSetMessages.RemoveWorkingSetElementAction_label);
	}

	@Override
	public void selectionChanged(IStructuredSelection selection) {
		IWorkingSet workingSet = getWorkingSet(selection);
		setEnabled(workingSet != null
				&& !WorkingSetIDs.OTHERS.equals(workingSet.getId()));
	}

	private IWorkingSet getWorkingSet(IStructuredSelection selection) {
		if (!(selection instanceof ITreeSelection))
			return null;
		ITreeSelection treeSelection = (ITreeSelection) selection;
		List elements = treeSelection.toList();
		IWorkingSet result = null;
		for (Iterator iter = elements.iterator(); iter.hasNext();) {
			Object element = iter.next();
			TreePath[] paths = treeSelection.getPathsFor(element);
			if (paths.length != 1)
				return null;
			TreePath path = paths[0];
			if (path.getSegmentCount() != 2)
				return null;
			Object candidate = path.getSegment(0);
			if (!(candidate instanceof IWorkingSet))
				return null;
			if (result == null) {
				result = (IWorkingSet) candidate;
			} else {
				if (result != candidate)
					return null;
			}
		}
		return result;
	}

	@Override
	public void run(IStructuredSelection selection) {
		IWorkingSet ws = getWorkingSet(selection);
		if (ws == null)
			return;
		List<IAdaptable> elements = new ArrayList<>(
				Arrays.asList(ws.getElements()));
		List selectedElements = selection.toList();
		for (Iterator iter = selectedElements.iterator(); iter.hasNext();) {
			elements.remove(iter.next());
		}
		ws.setElements(elements.toArray(new IAdaptable[elements.size()]));
	}
}