bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/dialogs/WorkingSetConfigurationBlock.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007, 2009 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
  *     Remy Chi Jian Suen <remy.suen@gmail.com> - bug 201661
  *******************************************************************************/
 package org.eclipse.ui.dialogs;

 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Comparator;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.StringTokenizer;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.jface.dialogs.Dialog;
 import org.eclipse.jface.dialogs.IDialogConstants;
 import org.eclipse.jface.dialogs.IDialogSettings;
 import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.window.Window;
 import org.eclipse.jface.wizard.IWizardPage;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.FontMetrics;
 import org.eclipse.swt.graphics.GC;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.ui.IWorkingSet;
 import org.eclipse.ui.IWorkingSetManager;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.internal.WorkbenchMessages;
 import org.eclipse.ui.internal.dialogs.SimpleWorkingSetSelectionDialog;

 import com.ibm.icu.text.Collator;

 /**
  * Instances of this class provide a reusable composite with controls that allow
  * the selection of working sets. This class is most useful in
  * {@link IWizardPage} instances that wish to create resources and pre-install
  * them into particular working sets.
  *
  * @since 3.4
  *
  */
 public class WorkingSetConfigurationBlock {

 	/**
 	 * Filters the given working sets such that the following is true: for each
 	 * IWorkingSet s in result: s.getId() is element of workingSetIds
 	 *
 	 * @param workingSets
 	 *            the array to filter
 	 * @param workingSetIds
 	 *            the acceptable working set ids
 	 * @return the filtered elements
 	 */
 	public static IWorkingSet[] filter(IWorkingSet[] workingSets,
 			String[] workingSetIds) {

 		// create a copy so we can sort the array without mucking it up for clients.
 		String[] workingSetIdsCopy = new String[workingSetIds.length];
 		System.arraycopy(workingSetIds, 0, workingSetIdsCopy, 0,
 				workingSetIds.length);
 		Arrays.sort(workingSetIdsCopy);

 		ArrayList result = new ArrayList();

 		for (int i = 0; i < workingSets.length; i++) {
 			if (Arrays.binarySearch(workingSetIdsCopy, workingSets[i].getId()) >= 0)
 				result.add(workingSets[i]);
 		}

 		return (IWorkingSet[]) result.toArray(new IWorkingSet[result.size()]);
 	}

 	/**
 	 * Empty working set array constant.
 	 */
 	private static final IWorkingSet[] EMPTY_WORKING_SET_ARRAY = new IWorkingSet[0];

 	private static final String WORKINGSET_SELECTION_HISTORY = "workingset_selection_history"; //$NON-NLS-1$
 	private static final int MAX_HISTORY_SIZE = 5;

 	private Label workingSetLabel;
 	private Combo workingSetCombo;
 	private Button selectButton;
 	private Button enableButton;

 	private IWorkingSet[] selectedWorkingSets;
 	private ArrayList selectionHistory;
 	private final IDialogSettings dialogSettings;
 	private final String[] workingSetTypeIds;

 	private final String selectLabel;

 	private final String comboLabel;

 	private final String addButtonLabel;

 	/**
 	 * Create a new instance of this working set block using default labels.
 	 *
 	 * @param workingSetIds
 	 *            working set ids from which the user can choose
 	 * @param settings
 	 *            to store/load the selection history
 	 */
 	public WorkingSetConfigurationBlock(String[] workingSetIds,
 			IDialogSettings settings) {
 		this(workingSetIds, settings, null, null, null);
 	}

 	/**
 	 * Create a new instance of this working set block using custom labels.
 	 *
 	 * @param workingSetIds
 	 *            working set ids from which the user can choose
 	 * @param settings
 	 *            to store/load the selection history
 	 * @param addButtonLabel
 	 *            the label to use for the checkable enablement button. May be
 	 *            <code>null</code> to use the default value.
 	 * @param comboLabel
 	 *            the label to use for the recent working set combo. May be
 	 *            <code>null</code> to use the default value.
 	 * @param selectLabel
 	 *            the label to use for the select button. May be
 	 *            <code>null</code> to use the default value.
 	 */
 	public WorkingSetConfigurationBlock(String[] workingSetIds,
 			IDialogSettings settings, String addButtonLabel, String comboLabel, String selectLabel) {
 		Assert.isNotNull(workingSetIds);
 		Assert.isNotNull(settings);

 		workingSetTypeIds = workingSetIds;
 		Arrays.sort(workingSetIds); // we'll be performing some searches with these later - presort them
 		selectedWorkingSets = EMPTY_WORKING_SET_ARRAY;
 		dialogSettings = settings;
 		selectionHistory = loadSelectionHistory(settings, workingSetIds);

 		this.addButtonLabel = addButtonLabel == null ? WorkbenchMessages.WorkingSetGroup_EnableWorkingSet_button
 				: addButtonLabel;
 		this.comboLabel = comboLabel == null ? WorkbenchMessages.WorkingSetConfigurationBlock_WorkingSetText_name
 				: comboLabel;
 		this.selectLabel = selectLabel == null ? WorkbenchMessages.WorkingSetConfigurationBlock_SelectWorkingSet_button
 				: selectLabel;
 	}


 	/**
 	 * Set the current selection in the workbench.
 	 *
 	 * @param selection
 	 *            the selection to present in the UI or <b>null</b>
 	 * @deprecated use
 	 *             {@link #setWorkingSets(IWorkingSet[])} and {@link #findApplicableWorkingSets(IStructuredSelection)}
 	 *             instead.
 	 */
 	public void setSelection(IStructuredSelection selection) {
 		selectedWorkingSets = findApplicableWorkingSets(selection);

 		if (workingSetCombo != null)
 			updateSelectedWorkingSets();
 	}

 	/**
 	 * Set the current selection of working sets. This array will be filtered to
 	 * contain only working sets that are applicable to this instance.
 	 *
 	 * @param workingSets
 	 *            the working sets
 	 */
 	public void setWorkingSets(IWorkingSet[] workingSets) {
 		selectedWorkingSets = filterWorkingSets(Arrays.asList(workingSets));
 		if (workingSetCombo != null)
 			updateSelectedWorkingSets();
 	}

 	/**
 	 * Retrieves a working set from the given <code>selection</code> or an
 	 * empty array if no working set could be retrieved. This selection is
 	 * filtered based on the criteria used to construct this instance.
 	 *
 	 * @param selection
 	 *            the selection to retrieve the working set from
 	 * @return the selected working set or an empty array
 	 */
 	public IWorkingSet[] findApplicableWorkingSets(
 			IStructuredSelection selection) {
 		if (selection == null)
 			return EMPTY_WORKING_SET_ARRAY;

 		return filterWorkingSets(selection.toList());
 	}

 	/**
 	 * Prune a list of working sets such that they all match the criteria set
 	 * out by this block.
 	 *
 	 * @param elements
 	 *            the elements to filter
 	 * @return the filtered elements
 	 */
 	private IWorkingSet[] filterWorkingSets(Collection elements) {
 		ArrayList result = new ArrayList();
 		for (Iterator iterator = elements.iterator(); iterator.hasNext();) {
 			Object element = iterator.next();
 			if (element instanceof IWorkingSet
 					&& verifyWorkingSet((IWorkingSet) element)) {
 				result.add(element);
 			}
 		}
 		return (IWorkingSet[]) result.toArray(new IWorkingSet[result.size()]);
 	}

 	/**
 	 * Verifies that the given working set is suitable for selection in this
 	 * block.
 	 *
 	 * @param workingSetCandidate
 	 *            the candidate to test
 	 * @return whether it is suitable
 	 */
 	private boolean verifyWorkingSet(IWorkingSet workingSetCandidate) {
 		return !workingSetCandidate.isAggregateWorkingSet()
 				&& Arrays.binarySearch(workingSetTypeIds, workingSetCandidate
 						.getId()) >= 0 ;
 	}

 	/**
 	 * Return the currently selected working sets. If the controls representing
 	 * this block are disabled this array will be empty regardless of the
 	 * currently selected values.
 	 *
 	 * @return the selected working sets
 	 */
 	public IWorkingSet[] getSelectedWorkingSets() {
 		if (enableButton.getSelection()) {
 			return selectedWorkingSets;
 		}
 		return EMPTY_WORKING_SET_ARRAY;
 	}

 	/**
 	 * Add this block to the <code>parent</parent>
 	 *
 	 * @param parent the parent to add the block to
 	 */
 	public void createContent(final Composite parent) {
 		int numColumn = 3;

 		Composite composite = new Composite(parent, SWT.NONE);
 		composite.setLayoutData(new GridData(SWT.FILL, SWT.TOP, true, false));
 		composite.setLayout(new GridLayout(numColumn, false));

 		enableButton = new Button(composite, SWT.CHECK);
 		enableButton
 				.setText(addButtonLabel);
 		GridData enableData = new GridData(SWT.FILL, SWT.CENTER, true, false);
 		enableData.horizontalSpan = numColumn;
 		enableButton.setLayoutData(enableData);
 		enableButton.setSelection(selectedWorkingSets.length > 0);

 		workingSetLabel = new Label(composite, SWT.NONE);
 		workingSetLabel
 				.setText(comboLabel);

 		workingSetCombo = new Combo(composite, SWT.READ_ONLY | SWT.BORDER);
 		GridData textData = new GridData(SWT.FILL, SWT.CENTER, true, false);
 		textData.horizontalSpan = numColumn - 2;
 		textData.horizontalIndent = 0;
 		workingSetCombo.setLayoutData(textData);

 		selectButton = new Button(composite, SWT.PUSH);
 		selectButton
 				.setText(selectLabel);
 		setButtonLayoutData(selectButton);
 		selectButton.addSelectionListener(new SelectionAdapter() {

 			public void widgetSelected(SelectionEvent e) {
 				SimpleWorkingSetSelectionDialog dialog = new SimpleWorkingSetSelectionDialog(
 						parent.getShell(), workingSetTypeIds,
 						selectedWorkingSets, false);
 				dialog
 						.setMessage(WorkbenchMessages.WorkingSetGroup_WorkingSetSelection_message);

 				if (dialog.open() == Window.OK) {
 					IWorkingSet[] result = dialog.getSelection();
 					if (result != null && result.length > 0) {
 						selectedWorkingSets = result;
 						PlatformUI.getWorkbench().getWorkingSetManager()
 								.addRecentWorkingSet(result[0]);
 					} else {
 						selectedWorkingSets = EMPTY_WORKING_SET_ARRAY;
 					}
 					updateWorkingSetSelection();
 				}
 			}
 		});

 		enableButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				updateEnableState(enableButton.getSelection());
 			}
 		});
 		updateEnableState(enableButton.getSelection());

 		workingSetCombo.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				updateSelectedWorkingSets();
 			}
 		});

 		workingSetCombo.setItems(getHistoryEntries());
 		if (selectedWorkingSets.length == 0 && selectionHistory.size() > 0) {
 			workingSetCombo.select(historyIndex((String) selectionHistory
 					.get(0)));
 			updateSelectedWorkingSets();
 		} else {
 			updateWorkingSetSelection();
 		}
 	}

 	private void updateEnableState(boolean enabled) {
 		workingSetLabel.setEnabled(enabled);
 		workingSetCombo
 				.setEnabled(enabled
 						&& (selectedWorkingSets.length > 0 || getHistoryEntries().length > 0));
 		selectButton.setEnabled(enabled);
 	}

 	private void updateWorkingSetSelection() {
 		if (selectedWorkingSets.length > 0) {
 			workingSetCombo.setEnabled(true);
 			StringBuffer buf = new StringBuffer();

 			buf.append(selectedWorkingSets[0].getLabel());
 			for (int i = 1; i < selectedWorkingSets.length; i++) {
 				IWorkingSet ws = selectedWorkingSets[i];
 				buf.append(',').append(' ');
 				buf.append(ws.getLabel());
 			}

 			String currentSelection = buf.toString();
 			int index = historyIndex(currentSelection);
 			historyInsert(currentSelection);
 			if (index >= 0) {
 				workingSetCombo.select(index);
 			} else {
 				workingSetCombo.setItems(getHistoryEntries());
 				workingSetCombo.select(historyIndex(currentSelection));
 			}
 		} else {
 			enableButton.setSelection(false);
 			updateEnableState(false);
 		}
 	}

 	private String[] getHistoryEntries() {
 		String[] history = (String[]) selectionHistory
 				.toArray(new String[selectionHistory.size()]);
 		Arrays.sort(history, new Comparator() {
 			public int compare(Object o1, Object o2) {
 				return Collator.getInstance().compare(o1, o2);
 			}
 		});
 		return history;
 	}

 	private void historyInsert(String entry) {
 		selectionHistory.remove(entry);
 		selectionHistory.add(0, entry);
 		storeSelectionHistory(dialogSettings);
 	}

 	private int historyIndex(String entry) {
 		for (int i = 0; i < workingSetCombo.getItemCount(); i++) {
 			if (workingSetCombo.getItem(i).equals(entry))
 				return i;
 		}

 		return -1;
 	}

 	// copied from org.eclipse.jdt.internal.ui.text.JavaCommentScanner
 	private String[] split(String value, String delimiters) {
 		StringTokenizer tokenizer= new StringTokenizer(value, delimiters);
 		int size= tokenizer.countTokens();
 		String[] tokens= new String[size];
 		int i= 0;
 		while (i < size)
 			tokens[i++]= tokenizer.nextToken();
 		return tokens;
 	}

 	private void updateSelectedWorkingSets() {
 		String item = workingSetCombo.getItem(workingSetCombo
 				.getSelectionIndex());
 		String[] workingSetNames = split(item, ", "); //$NON-NLS-1$

 		IWorkingSetManager workingSetManager = PlatformUI.getWorkbench()
 				.getWorkingSetManager();
 		selectedWorkingSets = new IWorkingSet[workingSetNames.length];
 		for (int i = 0; i < workingSetNames.length; i++) {
 			IWorkingSet set = workingSetManager
 					.getWorkingSet(workingSetNames[i]);
 			Assert.isNotNull(set);
 			selectedWorkingSets[i] = set;
 		}
 	}

 	private void storeSelectionHistory(IDialogSettings settings) {
 		String[] history;
 		if (selectionHistory.size() > MAX_HISTORY_SIZE) {
 			List subList = selectionHistory.subList(0, MAX_HISTORY_SIZE);
 			history = (String[]) subList.toArray(new String[subList.size()]);
 		} else {
 			history = (String[]) selectionHistory
 					.toArray(new String[selectionHistory.size()]);
 		}
 		settings.put(WORKINGSET_SELECTION_HISTORY, history);
 	}

 	private ArrayList loadSelectionHistory(IDialogSettings settings,
 			String[] workingSetIds) {
 		String[] strings = settings.getArray(WORKINGSET_SELECTION_HISTORY);
 		if (strings == null || strings.length == 0)
 			return new ArrayList();

 		ArrayList result = new ArrayList();

 		HashSet workingSetIdsSet = new HashSet(Arrays.asList(workingSetIds));

 		IWorkingSetManager workingSetManager = PlatformUI.getWorkbench()
 				.getWorkingSetManager();
 		for (int i = 0; i < strings.length; i++) {
 			String[] workingSetNames = split(strings[i], ", "); //$NON-NLS-1$
 			boolean valid = true;
 			for (int j = 0; j < workingSetNames.length && valid; j++) {
 				IWorkingSet workingSet = workingSetManager
 						.getWorkingSet(workingSetNames[j]);
 				if (workingSet == null) {
 					valid = false;
 				} else {
 					if (!workingSetIdsSet.contains(workingSet.getId()))
 						valid = false;
 				}
 			}
 			if (valid) {
 				result.add(strings[i]);
 			}
 		}

 		return result;
 	}

 	/*
 	 * Copy from DialogPage with changes to accomodate the lack of a Dialog context.
 	 */
 	private GridData setButtonLayoutData(Button button) {
 		button.setFont(JFaceResources.getDialogFont());

 		GC gc = new GC(button);
 		gc.setFont(button.getFont());
 		FontMetrics fontMetrics = gc.getFontMetrics();
 		gc.dispose();

         GridData data = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
         int widthHint = Dialog.convertHorizontalDLUsToPixels(fontMetrics, IDialogConstants.BUTTON_WIDTH);
         Point minSize = button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true);
         data.widthHint = Math.max(widthHint, minSize.x);
         button.setLayoutData(data);
         return data;
     }
 }
	/*******************************************************************************
	* Copyright (c) 2007, 2009 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
	* Remy Chi Jian Suen <remy.suen@gmail.com> - bug 201661
	*******************************************************************************/
	package org.eclipse.ui.dialogs;

	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.Comparator;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.List;
	import java.util.StringTokenizer;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.jface.dialogs.Dialog;
	import org.eclipse.jface.dialogs.IDialogConstants;
	import org.eclipse.jface.dialogs.IDialogSettings;
	import org.eclipse.jface.resource.JFaceResources;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.window.Window;
	import org.eclipse.jface.wizard.IWizardPage;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.FontMetrics;
	import org.eclipse.swt.graphics.GC;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Combo;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.ui.IWorkingSet;
	import org.eclipse.ui.IWorkingSetManager;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.internal.WorkbenchMessages;
	import org.eclipse.ui.internal.dialogs.SimpleWorkingSetSelectionDialog;

	import com.ibm.icu.text.Collator;

	/**
	* Instances of this class provide a reusable composite with controls that allow
	* the selection of working sets. This class is most useful in
	* {@link IWizardPage} instances that wish to create resources and pre-install
	* them into particular working sets.
	*
	* @since 3.4
	*
	*/
	public class WorkingSetConfigurationBlock {

	/**
	* Filters the given working sets such that the following is true: for each
	* IWorkingSet s in result: s.getId() is element of workingSetIds
	*
	* @param workingSets
	* the array to filter
	* @param workingSetIds
	* the acceptable working set ids
	* @return the filtered elements
	*/
	public static IWorkingSet[] filter(IWorkingSet[] workingSets,
	String[] workingSetIds) {

	// create a copy so we can sort the array without mucking it up for clients.
	String[] workingSetIdsCopy = new String[workingSetIds.length];
	System.arraycopy(workingSetIds, 0, workingSetIdsCopy, 0,
	workingSetIds.length);
	Arrays.sort(workingSetIdsCopy);

	ArrayList result = new ArrayList();

	for (int i = 0; i < workingSets.length; i++) {
	if (Arrays.binarySearch(workingSetIdsCopy, workingSets[i].getId()) >= 0)
	result.add(workingSets[i]);
	}

	return (IWorkingSet[]) result.toArray(new IWorkingSet[result.size()]);
	}

	/**
	* Empty working set array constant.
	*/
	private static final IWorkingSet[] EMPTY_WORKING_SET_ARRAY = new IWorkingSet[0];

	private static final String WORKINGSET_SELECTION_HISTORY = "workingset_selection_history"; //$NON-NLS-1$
	private static final int MAX_HISTORY_SIZE = 5;

	private Label workingSetLabel;
	private Combo workingSetCombo;
	private Button selectButton;
	private Button enableButton;

	private IWorkingSet[] selectedWorkingSets;
	private ArrayList selectionHistory;
	private final IDialogSettings dialogSettings;
	private final String[] workingSetTypeIds;

	private final String selectLabel;

	private final String comboLabel;

	private final String addButtonLabel;

	/**
	* Create a new instance of this working set block using default labels.
	*
	* @param workingSetIds
	* working set ids from which the user can choose
	* @param settings
	* to store/load the selection history
	*/
	public WorkingSetConfigurationBlock(String[] workingSetIds,
	IDialogSettings settings) {
	this(workingSetIds, settings, null, null, null);
	}

	/**
	* Create a new instance of this working set block using custom labels.
	*
	* @param workingSetIds
	* working set ids from which the user can choose
	* @param settings
	* to store/load the selection history
	* @param addButtonLabel
	* the label to use for the checkable enablement button. May be
	* <code>null</code> to use the default value.
	* @param comboLabel
	* the label to use for the recent working set combo. May be
	* <code>null</code> to use the default value.
	* @param selectLabel
	* the label to use for the select button. May be
	* <code>null</code> to use the default value.
	*/
	public WorkingSetConfigurationBlock(String[] workingSetIds,
	IDialogSettings settings, String addButtonLabel, String comboLabel, String selectLabel) {
	Assert.isNotNull(workingSetIds);
	Assert.isNotNull(settings);

	workingSetTypeIds = workingSetIds;
	Arrays.sort(workingSetIds); // we'll be performing some searches with these later - presort them
	selectedWorkingSets = EMPTY_WORKING_SET_ARRAY;
	dialogSettings = settings;
	selectionHistory = loadSelectionHistory(settings, workingSetIds);

	this.addButtonLabel = addButtonLabel == null ? WorkbenchMessages.WorkingSetGroup_EnableWorkingSet_button
	: addButtonLabel;
	this.comboLabel = comboLabel == null ? WorkbenchMessages.WorkingSetConfigurationBlock_WorkingSetText_name
	: comboLabel;
	this.selectLabel = selectLabel == null ? WorkbenchMessages.WorkingSetConfigurationBlock_SelectWorkingSet_button
	: selectLabel;
	}


	/**
	* Set the current selection in the workbench.
	*
	* @param selection
	* the selection to present in the UI or <b>null</b>
	* @deprecated use
	* {@link #setWorkingSets(IWorkingSet[])} and {@link #findApplicableWorkingSets(IStructuredSelection)}
	* instead.
	*/
	public void setSelection(IStructuredSelection selection) {
	selectedWorkingSets = findApplicableWorkingSets(selection);

	if (workingSetCombo != null)
	updateSelectedWorkingSets();
	}

	/**
	* Set the current selection of working sets. This array will be filtered to
	* contain only working sets that are applicable to this instance.
	*
	* @param workingSets
	* the working sets
	*/
	public void setWorkingSets(IWorkingSet[] workingSets) {
	selectedWorkingSets = filterWorkingSets(Arrays.asList(workingSets));
	if (workingSetCombo != null)
	updateSelectedWorkingSets();
	}

	/**
	* Retrieves a working set from the given <code>selection</code> or an
	* empty array if no working set could be retrieved. This selection is
	* filtered based on the criteria used to construct this instance.
	*
	* @param selection
	* the selection to retrieve the working set from
	* @return the selected working set or an empty array
	*/
	public IWorkingSet[] findApplicableWorkingSets(
	IStructuredSelection selection) {
	if (selection == null)
	return EMPTY_WORKING_SET_ARRAY;

	return filterWorkingSets(selection.toList());
	}

	/**
	* Prune a list of working sets such that they all match the criteria set
	* out by this block.
	*
	* @param elements
	* the elements to filter
	* @return the filtered elements
	*/
	private IWorkingSet[] filterWorkingSets(Collection elements) {
	ArrayList result = new ArrayList();
	for (Iterator iterator = elements.iterator(); iterator.hasNext();) {
	Object element = iterator.next();
	if (element instanceof IWorkingSet
	&& verifyWorkingSet((IWorkingSet) element)) {
	result.add(element);
	}
	}
	return (IWorkingSet[]) result.toArray(new IWorkingSet[result.size()]);
	}

	/**
	* Verifies that the given working set is suitable for selection in this
	* block.
	*
	* @param workingSetCandidate
	* the candidate to test
	* @return whether it is suitable
	*/
	private boolean verifyWorkingSet(IWorkingSet workingSetCandidate) {
	return !workingSetCandidate.isAggregateWorkingSet()
	&& Arrays.binarySearch(workingSetTypeIds, workingSetCandidate
	.getId()) >= 0 ;
	}

	/**
	* Return the currently selected working sets. If the controls representing
	* this block are disabled this array will be empty regardless of the
	* currently selected values.
	*
	* @return the selected working sets
	*/
	public IWorkingSet[] getSelectedWorkingSets() {
	if (enableButton.getSelection()) {
	return selectedWorkingSets;
	}
	return EMPTY_WORKING_SET_ARRAY;
	}

	/**
	* Add this block to the <code>parent</parent>
	*
	* @param parent the parent to add the block to
	*/
	public void createContent(final Composite parent) {
	int numColumn = 3;

	Composite composite = new Composite(parent, SWT.NONE);
	composite.setLayoutData(new GridData(SWT.FILL, SWT.TOP, true, false));
	composite.setLayout(new GridLayout(numColumn, false));

	enableButton = new Button(composite, SWT.CHECK);
	enableButton
	.setText(addButtonLabel);
	GridData enableData = new GridData(SWT.FILL, SWT.CENTER, true, false);
	enableData.horizontalSpan = numColumn;
	enableButton.setLayoutData(enableData);
	enableButton.setSelection(selectedWorkingSets.length > 0);

	workingSetLabel = new Label(composite, SWT.NONE);
	workingSetLabel
	.setText(comboLabel);

	workingSetCombo = new Combo(composite, SWT.READ_ONLY \| SWT.BORDER);
	GridData textData = new GridData(SWT.FILL, SWT.CENTER, true, false);
	textData.horizontalSpan = numColumn - 2;
	textData.horizontalIndent = 0;
	workingSetCombo.setLayoutData(textData);

	selectButton = new Button(composite, SWT.PUSH);
	selectButton
	.setText(selectLabel);
	setButtonLayoutData(selectButton);
	selectButton.addSelectionListener(new SelectionAdapter() {

	public void widgetSelected(SelectionEvent e) {
	SimpleWorkingSetSelectionDialog dialog = new SimpleWorkingSetSelectionDialog(
	parent.getShell(), workingSetTypeIds,
	selectedWorkingSets, false);
	dialog
	.setMessage(WorkbenchMessages.WorkingSetGroup_WorkingSetSelection_message);

	if (dialog.open() == Window.OK) {
	IWorkingSet[] result = dialog.getSelection();
	if (result != null && result.length > 0) {
	selectedWorkingSets = result;
	PlatformUI.getWorkbench().getWorkingSetManager()
	.addRecentWorkingSet(result[0]);
	} else {
	selectedWorkingSets = EMPTY_WORKING_SET_ARRAY;
	}
	updateWorkingSetSelection();
	}
	}
	});

	enableButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	updateEnableState(enableButton.getSelection());
	}
	});
	updateEnableState(enableButton.getSelection());

	workingSetCombo.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	updateSelectedWorkingSets();
	}
	});

	workingSetCombo.setItems(getHistoryEntries());
	if (selectedWorkingSets.length == 0 && selectionHistory.size() > 0) {
	workingSetCombo.select(historyIndex((String) selectionHistory
	.get(0)));
	updateSelectedWorkingSets();
	} else {
	updateWorkingSetSelection();
	}
	}

	private void updateEnableState(boolean enabled) {
	workingSetLabel.setEnabled(enabled);
	workingSetCombo
	.setEnabled(enabled
	&& (selectedWorkingSets.length > 0 \|\| getHistoryEntries().length > 0));
	selectButton.setEnabled(enabled);
	}

	private void updateWorkingSetSelection() {
	if (selectedWorkingSets.length > 0) {
	workingSetCombo.setEnabled(true);
	StringBuffer buf = new StringBuffer();

	buf.append(selectedWorkingSets[0].getLabel());
	for (int i = 1; i < selectedWorkingSets.length; i++) {
	IWorkingSet ws = selectedWorkingSets[i];
	buf.append(',').append(' ');
	buf.append(ws.getLabel());
	}

	String currentSelection = buf.toString();
	int index = historyIndex(currentSelection);
	historyInsert(currentSelection);
	if (index >= 0) {
	workingSetCombo.select(index);
	} else {
	workingSetCombo.setItems(getHistoryEntries());
	workingSetCombo.select(historyIndex(currentSelection));
	}
	} else {
	enableButton.setSelection(false);
	updateEnableState(false);
	}
	}

	private String[] getHistoryEntries() {
	String[] history = (String[]) selectionHistory
	.toArray(new String[selectionHistory.size()]);
	Arrays.sort(history, new Comparator() {
	public int compare(Object o1, Object o2) {
	return Collator.getInstance().compare(o1, o2);
	}
	});
	return history;
	}

	private void historyInsert(String entry) {
	selectionHistory.remove(entry);
	selectionHistory.add(0, entry);
	storeSelectionHistory(dialogSettings);
	}

	private int historyIndex(String entry) {
	for (int i = 0; i < workingSetCombo.getItemCount(); i++) {
	if (workingSetCombo.getItem(i).equals(entry))
	return i;
	}

	return -1;
	}

	// copied from org.eclipse.jdt.internal.ui.text.JavaCommentScanner
	private String[] split(String value, String delimiters) {
	StringTokenizer tokenizer= new StringTokenizer(value, delimiters);
	int size= tokenizer.countTokens();
	String[] tokens= new String[size];
	int i= 0;
	while (i < size)
	tokens[i++]= tokenizer.nextToken();
	return tokens;
	}

	private void updateSelectedWorkingSets() {
	String item = workingSetCombo.getItem(workingSetCombo
	.getSelectionIndex());
	String[] workingSetNames = split(item, ", "); //$NON-NLS-1$

	IWorkingSetManager workingSetManager = PlatformUI.getWorkbench()
	.getWorkingSetManager();
	selectedWorkingSets = new IWorkingSet[workingSetNames.length];
	for (int i = 0; i < workingSetNames.length; i++) {
	IWorkingSet set = workingSetManager
	.getWorkingSet(workingSetNames[i]);
	Assert.isNotNull(set);
	selectedWorkingSets[i] = set;
	}
	}

	private void storeSelectionHistory(IDialogSettings settings) {
	String[] history;
	if (selectionHistory.size() > MAX_HISTORY_SIZE) {
	List subList = selectionHistory.subList(0, MAX_HISTORY_SIZE);
	history = (String[]) subList.toArray(new String[subList.size()]);
	} else {
	history = (String[]) selectionHistory
	.toArray(new String[selectionHistory.size()]);
	}
	settings.put(WORKINGSET_SELECTION_HISTORY, history);
	}

	private ArrayList loadSelectionHistory(IDialogSettings settings,
	String[] workingSetIds) {
	String[] strings = settings.getArray(WORKINGSET_SELECTION_HISTORY);
	if (strings == null \|\| strings.length == 0)
	return new ArrayList();

	ArrayList result = new ArrayList();

	HashSet workingSetIdsSet = new HashSet(Arrays.asList(workingSetIds));

	IWorkingSetManager workingSetManager = PlatformUI.getWorkbench()
	.getWorkingSetManager();
	for (int i = 0; i < strings.length; i++) {
	String[] workingSetNames = split(strings[i], ", "); //$NON-NLS-1$
	boolean valid = true;
	for (int j = 0; j < workingSetNames.length && valid; j++) {
	IWorkingSet workingSet = workingSetManager
	.getWorkingSet(workingSetNames[j]);
	if (workingSet == null) {
	valid = false;
	} else {
	if (!workingSetIdsSet.contains(workingSet.getId()))
	valid = false;
	}
	}
	if (valid) {
	result.add(strings[i]);
	}
	}

	return result;
	}

	/*
	* Copy from DialogPage with changes to accomodate the lack of a Dialog context.
	*/
	private GridData setButtonLayoutData(Button button) {
	button.setFont(JFaceResources.getDialogFont());

	GC gc = new GC(button);
	gc.setFont(button.getFont());
	FontMetrics fontMetrics = gc.getFontMetrics();
	gc.dispose();

	GridData data = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
	int widthHint = Dialog.convertHorizontalDLUsToPixels(fontMetrics, IDialogConstants.BUTTON_WIDTH);
	Point minSize = button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true);
	data.widthHint = Math.max(widthHint, minSize.x);
	button.setLayoutData(data);
	return data;
	}
	}