bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/IDEWorkbenchPreferencePage.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.ide.dialogs;

 import java.io.UnsupportedEncodingException;
 import java.util.ArrayList;
 import java.util.Collections;

 import org.eclipse.core.resources.IWorkspaceDescription;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.Preferences;
 import org.eclipse.jface.dialogs.IDialogConstants;
 import org.eclipse.jface.preference.FieldEditor;
 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.preference.IntegerFieldEditor;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.preference.RadioGroupFieldEditor;
 import org.eclipse.jface.preference.StringFieldEditor;
 import org.eclipse.jface.util.IPropertyChangeListener;
 import org.eclipse.jface.util.PropertyChangeEvent;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.ModifyEvent;
 import org.eclipse.swt.events.ModifyListener;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Font;
 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.Control;
 import org.eclipse.swt.widgets.Group;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.IWorkbenchPreferencePage;
 import org.eclipse.ui.help.WorkbenchHelp;
 import org.eclipse.ui.internal.ide.IDEInternalPreferences;
 import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;
 import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin;
 import org.eclipse.ui.internal.ide.IHelpContextIds;

 /**
  * The IDE workbench main preference page.
  */
 public class IDEWorkbenchPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {
 	private final String PROJECT_SWITCH_PERSP_MODE_TITLE = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.optionsTitle"); //$NON-NLS-1$
 	private final String PSPM_ALWAYS_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.always"); //$NON-NLS-1$
 	private final String PSPM_NEVER_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.never"); //$NON-NLS-1$
 	private final String PSPM_PROMPT_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.prompt"); //$NON-NLS-1$

 	private Button autoBuildButton;
 	private Button autoSaveAllButton;
 	private Button refreshButton;
 	private Button showTasks;
 	private Button exitPromptButton;
 	private IntegerFieldEditor saveInterval;

 	// State for encoding group
 	private String defaultEnc;
 	private Button defaultEncodingButton;
 	private Button otherEncodingButton;
 	private Combo encodingCombo;

 	private RadioGroupFieldEditor projectSwitchField;

 	/**
 	 *	Create this page's visual contents
 	 *
 	 *	@return org.eclipse.swt.widgets.Control
 	 *	@param parent org.eclipse.swt.widgets.Composite
 	 */
 	protected Control createContents(Composite parent) {

 		Font font = parent.getFont();

 		WorkbenchHelp.setHelp(parent, IHelpContextIds.WORKBENCH_PREFERENCE_PAGE);

 		Composite composite = new Composite(parent, SWT.NULL);
 		GridLayout layout = new GridLayout();
 		layout.marginWidth = 0;
 		layout.marginHeight = 0;
 		composite.setLayout(layout);
 		composite.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_FILL | GridData.HORIZONTAL_ALIGN_FILL));
 		composite.setFont(font);

 		autoBuildButton = new Button(composite, SWT.CHECK);
 		autoBuildButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.autobuild")); //$NON-NLS-1$
 		autoBuildButton.setFont(font);

 		autoSaveAllButton = new Button(composite, SWT.CHECK);
 		autoSaveAllButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.savePriorToBuilding")); //$NON-NLS-1$
 		autoSaveAllButton.setFont(font);

 		refreshButton = new Button(composite, SWT.CHECK);
 		refreshButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.refreshButton")); //$NON-NLS-1$
 		refreshButton.setFont(font);

 		exitPromptButton = new Button(composite, SWT.CHECK);
 		exitPromptButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.exitPromptButton")); //$NON-NLS-1$
 		exitPromptButton.setFont(font);

 		showTasks = new Button(composite, SWT.CHECK);
 		showTasks.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.showTasks")); //$NON-NLS-1$
 		showTasks.setFont(font);

 		createSpace(composite);
 		createSaveIntervalGroup(composite);

 		createSpace(composite);
 		createEncodingGroup(composite);

 		createSpace(composite);
 		createProjectPerspectiveGroup(composite);

 		// set initial values
 		IPreferenceStore store = getPreferenceStore();
 		autoBuildButton.setSelection(ResourcesPlugin.getWorkspace().isAutoBuilding());
 		autoSaveAllButton.setSelection(store.getBoolean(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD));
 		refreshButton.setSelection(store.getBoolean(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP));
 		exitPromptButton.setSelection(store.getBoolean(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW));
 		showTasks.setSelection(store.getBoolean(IDEInternalPreferences.SHOW_TASKS_ON_BUILD));

 		return composite;
 	}

 	/**
 	 * Create a composite that contains entry fields specifying save interval preference.
 	 */
 	private void createSaveIntervalGroup(Composite composite) {
 		Composite groupComposite = new Composite(composite, SWT.LEFT);
 		GridLayout layout = new GridLayout();
 		layout.numColumns = 2;
 		groupComposite.setLayout(layout);
 		GridData gd = new GridData();
 		gd.horizontalAlignment = GridData.FILL;
 		gd.grabExcessHorizontalSpace = true;
 		groupComposite.setLayoutData(gd);
 		groupComposite.setFont(composite.getFont());

 		saveInterval = new IntegerFieldEditor(IDEInternalPreferences.SAVE_INTERVAL, IDEWorkbenchMessages.getString("WorkbenchPreference.saveInterval"), groupComposite); //$NON-NLS-1$

 		// @issue we should drop our preference constant and let clients use core's pref. ours is not up-to-date anyway if someone changes this interval directly thru core api.
 		saveInterval.setPreferenceStore(getPreferenceStore());
 		saveInterval.setPreferencePage(this);
 		saveInterval.setTextLimit(Integer.toString(IDEInternalPreferences.MAX_SAVE_INTERVAL).length());
 		saveInterval.setErrorMessage(IDEWorkbenchMessages.format("WorkbenchPreference.saveIntervalError", new Object[] { new Integer(IDEInternalPreferences.MAX_SAVE_INTERVAL)})); //$NON-NLS-1$
 		saveInterval.setValidateStrategy(StringFieldEditor.VALIDATE_ON_KEY_STROKE);
 		saveInterval.setValidRange(1, IDEInternalPreferences.MAX_SAVE_INTERVAL);

 		IWorkspaceDescription description = ResourcesPlugin.getWorkspace().getDescription();
 		long interval = description.getSnapshotInterval() / 60000;
 		saveInterval.setStringValue(Long.toString(interval));

 		saveInterval.setPropertyChangeListener(new IPropertyChangeListener() {
 			public void propertyChange(PropertyChangeEvent event) {
 				if (event.getProperty().equals(FieldEditor.IS_VALID))
 					setValid(saveInterval.isValid());
 			}
 		});

 	}

 	private void createEncodingGroup(Composite parent) {

 		Font font = parent.getFont();
 		Group group = new Group(parent, SWT.NONE);
 		GridData data = new GridData(GridData.FILL_HORIZONTAL);
 		group.setLayoutData(data);
 		GridLayout layout = new GridLayout();
 		layout.numColumns = 2;
 		group.setLayout(layout);
 		group.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.encoding")); //$NON-NLS-1$
 		group.setFont(font);

 		SelectionAdapter buttonListener = new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				updateEncodingState(defaultEncodingButton.getSelection());
 				updateValidState();
 			}
 		};

 		defaultEncodingButton = new Button(group, SWT.RADIO);
 		defaultEnc = System.getProperty("file.encoding", "UTF-8");  //$NON-NLS-1$  //$NON-NLS-2$
 		defaultEncodingButton.setText(IDEWorkbenchMessages.format("WorkbenchPreference.defaultEncoding", new String[] { defaultEnc })); //$NON-NLS-1$
 		data = new GridData();
 		data.horizontalSpan = 2;
 		defaultEncodingButton.setLayoutData(data);
 		defaultEncodingButton.addSelectionListener(buttonListener);
 		defaultEncodingButton.setFont(font);

 		otherEncodingButton = new Button(group, SWT.RADIO);
 		otherEncodingButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.otherEncoding")); //$NON-NLS-1$
 		otherEncodingButton.addSelectionListener(buttonListener);
 		otherEncodingButton.setFont(font);

 		encodingCombo = new Combo(group, SWT.NONE);
 		data = new GridData();
 		data.widthHint = convertWidthInCharsToPixels(15);
 		encodingCombo.setFont(font);
 		encodingCombo.setLayoutData(data);
 		encodingCombo.addModifyListener(new ModifyListener() {
 			public void modifyText(ModifyEvent e) {
 				updateValidState();
 			}
 		});

 		ArrayList encodings = new ArrayList();
 		int n = 0;
 		try {
 			n = Integer.parseInt(IDEWorkbenchMessages.getString("WorkbenchPreference.numDefaultEncodings")); //$NON-NLS-1$
 		}
 		catch (NumberFormatException e) {
 			// Ignore;
 		}
 		for (int i = 0; i < n; ++i) {
 			String enc = IDEWorkbenchMessages.getString("WorkbenchPreference.defaultEncoding" + (i+1), null); //$NON-NLS-1$
 			if (enc != null) {
 				encodings.add(enc);
 			}
 		}

 		if (!encodings.contains(defaultEnc)) {
 			encodings.add(defaultEnc);
 		}

 		String enc = ResourcesPlugin.getPlugin().getPluginPreferences().getString(ResourcesPlugin.PREF_ENCODING);
 		boolean isDefault = enc == null || enc.length() == 0;

 		if (!isDefault && !encodings.contains(enc)) {
 			encodings.add(enc);
 		}
 		Collections.sort(encodings);
 		for (int i = 0; i < encodings.size(); ++i) {
 			encodingCombo.add((String) encodings.get(i));
 		}

 		encodingCombo.setText(isDefault ? defaultEnc : enc);

 		updateEncodingState(isDefault);
 	}

 	private void updateValidState() {
 		if (!isEncodingValid()) {
 			setErrorMessage(IDEWorkbenchMessages.getString("WorkbenchPreference.unsupportedEncoding")); //$NON-NLS-1$
 			setValid(false);
 		} else {
 			setErrorMessage(null);
 			setValid(true);
 		}
 	}

 	private boolean isEncodingValid() {
 		return defaultEncodingButton.getSelection() ||
 			isValidEncoding(encodingCombo.getText());
 	}

 	private boolean isValidEncoding(String enc) {
 		try {
 			new String(new byte[0], enc);
 			return true;
 		} catch (UnsupportedEncodingException e) {
 			return false;
 		}
 	}

 	private void updateEncodingState(boolean useDefault) {
 		defaultEncodingButton.setSelection(useDefault);
 		otherEncodingButton.setSelection(!useDefault);
 		encodingCombo.setEnabled(!useDefault);
 		updateValidState();
 	}

 	/**
 	 * Create a composite that contains buttons for selecting the
 	 * preference opening new project selections.
 	 */
 	private void createProjectPerspectiveGroup(Composite composite) {

 		Composite projectComposite = new Composite(composite, SWT.NONE);
 		projectComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
 		projectComposite.setFont(composite.getFont());

 		String[][] namesAndValues = {
 			{PSPM_ALWAYS_TEXT, IDEInternalPreferences.PSPM_ALWAYS},
 			{PSPM_NEVER_TEXT, IDEInternalPreferences.PSPM_NEVER},
 			{PSPM_PROMPT_TEXT, IDEInternalPreferences.PSPM_PROMPT}
 		};
 		projectSwitchField =	new RadioGroupFieldEditor(
 			IDEInternalPreferences.PROJECT_SWITCH_PERSP_MODE,
 			PROJECT_SWITCH_PERSP_MODE_TITLE,
 			namesAndValues.length,
 			namesAndValues,
 			projectComposite,
 			true);
 		projectSwitchField.setPreferenceStore(getPreferenceStore());
 		projectSwitchField.setPreferencePage(this);
 		projectSwitchField.load();
 	}

 	/**
 	 * Utility method that creates a radio button instance
 	 * and sets the default layout data.
 	 *
 	 * @param parent  the parent for the new button
 	 * @param label  the label for the new button
 	 * @return the newly-created button
 	 */
 	protected static Button createRadioButton(Composite parent, String label) {
 		Button button = new Button(parent, SWT.RADIO | SWT.LEFT);
 		button.setText(label);
 		button.setFont(parent.getFont());
 		return button;
 	}

 	/**
 	 * Utility method that creates a combo box
 	 *
 	 * @param parent  the parent for the new label
 	 * @return the new widget
 	 */
 	protected static Combo createCombo(Composite parent) {
 		Combo combo = new Combo(parent, SWT.READ_ONLY);
 		GridData data = new GridData(GridData.FILL_HORIZONTAL);
 		data.widthHint = IDialogConstants.ENTRY_FIELD_WIDTH;
 		combo.setLayoutData(data);
 		combo.setFont(parent.getFont());
 		return combo;
 	}

 	/**
 	 * Utility method that creates a label instance
 	 * and sets the default layout data.
 	 *
 	 * @param parent  the parent for the new label
 	 * @param text  the text for the new label
 	 * @return the new label
 	 */
 	protected static Label createLabel(Composite parent, String text) {
 		Label label = new Label(parent, SWT.LEFT);
 		label.setText(text);
 		label.setFont(parent.getFont());
 		GridData data = new GridData();
 		data.horizontalSpan = 1;
 		data.horizontalAlignment = GridData.FILL;
 		label.setLayoutData(data);
 		return label;
 	}

 	/**
 	 * Creates a tab of one horizontal spans.
 	 *
 	 * @param parent  the parent in which the tab should be created
 	 */
 	protected static void createSpace(Composite parent) {
 		Label vfiller = new Label(parent, SWT.LEFT);
 		GridData gridData = new GridData();
 		gridData = new GridData();
 		gridData.horizontalAlignment = GridData.BEGINNING;
 		gridData.grabExcessHorizontalSpace = false;
 		gridData.verticalAlignment = GridData.CENTER;
 		gridData.grabExcessVerticalSpace = false;
 		vfiller.setLayoutData(gridData);
 	}

 	/**
 	 * Returns preference store that belongs to the our plugin.
 	 *
 	 * @return the preference store for this plugin
 	 */
 	protected IPreferenceStore doGetPreferenceStore() {
 		return IDEWorkbenchPlugin.getDefault().getPreferenceStore();
 	}

 	/**
 	 *	@see IWorkbenchPreferencePage
 	 */
 	public void init(IWorkbench aWorkbench) {
 		// do nothing
 	}

 	/**
 	 * The default button has been pressed.
 	 */
 	protected void performDefaults() {
 		updateEncodingState(true);

 		// core holds onto this preference.
 		boolean autoBuild = ResourcesPlugin.getPlugin().getPluginPreferences().getDefaultBoolean(ResourcesPlugin.PREF_AUTO_BUILDING);
 		autoBuildButton.setSelection(autoBuild);

 		IPreferenceStore store = getPreferenceStore();
 		autoSaveAllButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD));
 		refreshButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP));
 		exitPromptButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW));
 		showTasks.setSelection(store.getBoolean(IDEInternalPreferences.SHOW_TASKS_ON_BUILD));
 		saveInterval.loadDefault();

 		projectSwitchField.loadDefault();

 		super.performDefaults();
 	}

 	/**
 	 *	The user has pressed Ok.  Store/apply this page's values appropriately.
 	 */
 	public boolean performOk() {
 		// set the workspace auto-build flag
 		IWorkspaceDescription description = ResourcesPlugin.getWorkspace().getDescription();
 		if (autoBuildButton.getSelection() != ResourcesPlugin.getWorkspace().isAutoBuilding()) {
 			try {
 				description.setAutoBuilding(autoBuildButton.getSelection());
 				ResourcesPlugin.getWorkspace().setDescription(description);
 			} catch (CoreException e) {
 				IDEWorkbenchPlugin.log("Error changing auto build workspace setting.", e.getStatus()); //$NON-NLS-1$
 			}
 		}

 		// set the workspace text file encoding
 		Preferences resourcePrefs = ResourcesPlugin.getPlugin().getPluginPreferences();
 		if (defaultEncodingButton.getSelection()) {
 			resourcePrefs.setToDefault(ResourcesPlugin.PREF_ENCODING);
 		}
 		else {
 			String enc = encodingCombo.getText();
 			resourcePrefs.setValue(ResourcesPlugin.PREF_ENCODING, enc);
 		}
 		ResourcesPlugin.getPlugin().savePluginPreferences();

 		IPreferenceStore store = getPreferenceStore();

 		// store the save all prior to build setting
 		store.setValue(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD, autoSaveAllButton.getSelection());

 		// store the refresh workspace on startup setting
 		store.setValue(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP, refreshButton.getSelection());

 		// store the exit prompt on last window close setting
 		store.setValue(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW, exitPromptButton.getSelection());

 		// store the preference for bringing task view to front on build
 		store.setValue(IDEInternalPreferences.SHOW_TASKS_ON_BUILD, showTasks.getSelection());

 		// store the workspace save interval
 		// @issue we should drop our preference constant and let clients use core's pref. ours is not up-to-date anyway if someone changes this interval directly thru core api.
 		long oldSaveInterval = description.getSnapshotInterval() / 60000;
 		long newSaveInterval = new Long(saveInterval.getStringValue()).longValue();
 		if (oldSaveInterval != newSaveInterval) {
 			try {
 				description.setSnapshotInterval(newSaveInterval * 60000);
 				ResourcesPlugin.getWorkspace().setDescription(description);
 				store.firePropertyChangeEvent(IDEInternalPreferences.SAVE_INTERVAL, new Integer((int)oldSaveInterval), new Integer((int)newSaveInterval));
 			} catch (CoreException e) {
 				IDEWorkbenchPlugin.log("Error changing save interval preference", e.getStatus()); //$NON-NLS-1$
 			}
 		}

 		// store the open new project perspective settings
 		projectSwitchField.store();

 		IDEWorkbenchPlugin.getDefault().savePluginPreferences();
 		return true;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2003 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.internal.ide.dialogs;

	import java.io.UnsupportedEncodingException;
	import java.util.ArrayList;
	import java.util.Collections;

	import org.eclipse.core.resources.IWorkspaceDescription;
	import org.eclipse.core.resources.ResourcesPlugin;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.Preferences;
	import org.eclipse.jface.dialogs.IDialogConstants;
	import org.eclipse.jface.preference.FieldEditor;
	import org.eclipse.jface.preference.IPreferenceStore;
	import org.eclipse.jface.preference.IntegerFieldEditor;
	import org.eclipse.jface.preference.PreferencePage;
	import org.eclipse.jface.preference.RadioGroupFieldEditor;
	import org.eclipse.jface.preference.StringFieldEditor;
	import org.eclipse.jface.util.IPropertyChangeListener;
	import org.eclipse.jface.util.PropertyChangeEvent;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.ModifyEvent;
	import org.eclipse.swt.events.ModifyListener;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Font;
	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.Control;
	import org.eclipse.swt.widgets.Group;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.IWorkbenchPreferencePage;
	import org.eclipse.ui.help.WorkbenchHelp;
	import org.eclipse.ui.internal.ide.IDEInternalPreferences;
	import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;
	import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin;
	import org.eclipse.ui.internal.ide.IHelpContextIds;

	/**
	* The IDE workbench main preference page.
	*/
	public class IDEWorkbenchPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {
	private final String PROJECT_SWITCH_PERSP_MODE_TITLE = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.optionsTitle"); //$NON-NLS-1$
	private final String PSPM_ALWAYS_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.always"); //$NON-NLS-1$
	private final String PSPM_NEVER_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.never"); //$NON-NLS-1$
	private final String PSPM_PROMPT_TEXT = IDEWorkbenchMessages.getString("ProjectSwitchPerspectiveMode.prompt"); //$NON-NLS-1$

	private Button autoBuildButton;
	private Button autoSaveAllButton;
	private Button refreshButton;
	private Button showTasks;
	private Button exitPromptButton;
	private IntegerFieldEditor saveInterval;

	// State for encoding group
	private String defaultEnc;
	private Button defaultEncodingButton;
	private Button otherEncodingButton;
	private Combo encodingCombo;

	private RadioGroupFieldEditor projectSwitchField;

	/**
	* Create this page's visual contents
	*
	* @return org.eclipse.swt.widgets.Control
	* @param parent org.eclipse.swt.widgets.Composite
	*/
	protected Control createContents(Composite parent) {

	Font font = parent.getFont();

	WorkbenchHelp.setHelp(parent, IHelpContextIds.WORKBENCH_PREFERENCE_PAGE);

	Composite composite = new Composite(parent, SWT.NULL);
	GridLayout layout = new GridLayout();
	layout.marginWidth = 0;
	layout.marginHeight = 0;
	composite.setLayout(layout);
	composite.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_FILL \| GridData.HORIZONTAL_ALIGN_FILL));
	composite.setFont(font);

	autoBuildButton = new Button(composite, SWT.CHECK);
	autoBuildButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.autobuild")); //$NON-NLS-1$
	autoBuildButton.setFont(font);

	autoSaveAllButton = new Button(composite, SWT.CHECK);
	autoSaveAllButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.savePriorToBuilding")); //$NON-NLS-1$
	autoSaveAllButton.setFont(font);

	refreshButton = new Button(composite, SWT.CHECK);
	refreshButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.refreshButton")); //$NON-NLS-1$
	refreshButton.setFont(font);

	exitPromptButton = new Button(composite, SWT.CHECK);
	exitPromptButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.exitPromptButton")); //$NON-NLS-1$
	exitPromptButton.setFont(font);

	showTasks = new Button(composite, SWT.CHECK);
	showTasks.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.showTasks")); //$NON-NLS-1$
	showTasks.setFont(font);

	createSpace(composite);
	createSaveIntervalGroup(composite);

	createSpace(composite);
	createEncodingGroup(composite);

	createSpace(composite);
	createProjectPerspectiveGroup(composite);

	// set initial values
	IPreferenceStore store = getPreferenceStore();
	autoBuildButton.setSelection(ResourcesPlugin.getWorkspace().isAutoBuilding());
	autoSaveAllButton.setSelection(store.getBoolean(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD));
	refreshButton.setSelection(store.getBoolean(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP));
	exitPromptButton.setSelection(store.getBoolean(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW));
	showTasks.setSelection(store.getBoolean(IDEInternalPreferences.SHOW_TASKS_ON_BUILD));

	return composite;
	}

	/**
	* Create a composite that contains entry fields specifying save interval preference.
	*/
	private void createSaveIntervalGroup(Composite composite) {
	Composite groupComposite = new Composite(composite, SWT.LEFT);
	GridLayout layout = new GridLayout();
	layout.numColumns = 2;
	groupComposite.setLayout(layout);
	GridData gd = new GridData();
	gd.horizontalAlignment = GridData.FILL;
	gd.grabExcessHorizontalSpace = true;
	groupComposite.setLayoutData(gd);
	groupComposite.setFont(composite.getFont());

	saveInterval = new IntegerFieldEditor(IDEInternalPreferences.SAVE_INTERVAL, IDEWorkbenchMessages.getString("WorkbenchPreference.saveInterval"), groupComposite); //$NON-NLS-1$

	// @issue we should drop our preference constant and let clients use core's pref. ours is not up-to-date anyway if someone changes this interval directly thru core api.
	saveInterval.setPreferenceStore(getPreferenceStore());
	saveInterval.setPreferencePage(this);
	saveInterval.setTextLimit(Integer.toString(IDEInternalPreferences.MAX_SAVE_INTERVAL).length());
	saveInterval.setErrorMessage(IDEWorkbenchMessages.format("WorkbenchPreference.saveIntervalError", new Object[] { new Integer(IDEInternalPreferences.MAX_SAVE_INTERVAL)})); //$NON-NLS-1$
	saveInterval.setValidateStrategy(StringFieldEditor.VALIDATE_ON_KEY_STROKE);
	saveInterval.setValidRange(1, IDEInternalPreferences.MAX_SAVE_INTERVAL);

	IWorkspaceDescription description = ResourcesPlugin.getWorkspace().getDescription();
	long interval = description.getSnapshotInterval() / 60000;
	saveInterval.setStringValue(Long.toString(interval));

	saveInterval.setPropertyChangeListener(new IPropertyChangeListener() {
	public void propertyChange(PropertyChangeEvent event) {
	if (event.getProperty().equals(FieldEditor.IS_VALID))
	setValid(saveInterval.isValid());
	}
	});

	}

	private void createEncodingGroup(Composite parent) {

	Font font = parent.getFont();
	Group group = new Group(parent, SWT.NONE);
	GridData data = new GridData(GridData.FILL_HORIZONTAL);
	group.setLayoutData(data);
	GridLayout layout = new GridLayout();
	layout.numColumns = 2;
	group.setLayout(layout);
	group.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.encoding")); //$NON-NLS-1$
	group.setFont(font);

	SelectionAdapter buttonListener = new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	updateEncodingState(defaultEncodingButton.getSelection());
	updateValidState();
	}
	};

	defaultEncodingButton = new Button(group, SWT.RADIO);
	defaultEnc = System.getProperty("file.encoding", "UTF-8"); //$NON-NLS-1$ //$NON-NLS-2$
	defaultEncodingButton.setText(IDEWorkbenchMessages.format("WorkbenchPreference.defaultEncoding", new String[] { defaultEnc })); //$NON-NLS-1$
	data = new GridData();
	data.horizontalSpan = 2;
	defaultEncodingButton.setLayoutData(data);
	defaultEncodingButton.addSelectionListener(buttonListener);
	defaultEncodingButton.setFont(font);

	otherEncodingButton = new Button(group, SWT.RADIO);
	otherEncodingButton.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.otherEncoding")); //$NON-NLS-1$
	otherEncodingButton.addSelectionListener(buttonListener);
	otherEncodingButton.setFont(font);

	encodingCombo = new Combo(group, SWT.NONE);
	data = new GridData();
	data.widthHint = convertWidthInCharsToPixels(15);
	encodingCombo.setFont(font);
	encodingCombo.setLayoutData(data);
	encodingCombo.addModifyListener(new ModifyListener() {
	public void modifyText(ModifyEvent e) {
	updateValidState();
	}
	});

	ArrayList encodings = new ArrayList();
	int n = 0;
	try {
	n = Integer.parseInt(IDEWorkbenchMessages.getString("WorkbenchPreference.numDefaultEncodings")); //$NON-NLS-1$
	}
	catch (NumberFormatException e) {
	// Ignore;
	}
	for (int i = 0; i < n; ++i) {
	String enc = IDEWorkbenchMessages.getString("WorkbenchPreference.defaultEncoding" + (i+1), null); //$NON-NLS-1$
	if (enc != null) {
	encodings.add(enc);
	}
	}

	if (!encodings.contains(defaultEnc)) {
	encodings.add(defaultEnc);
	}

	String enc = ResourcesPlugin.getPlugin().getPluginPreferences().getString(ResourcesPlugin.PREF_ENCODING);
	boolean isDefault = enc == null \|\| enc.length() == 0;

	if (!isDefault && !encodings.contains(enc)) {
	encodings.add(enc);
	}
	Collections.sort(encodings);
	for (int i = 0; i < encodings.size(); ++i) {
	encodingCombo.add((String) encodings.get(i));
	}

	encodingCombo.setText(isDefault ? defaultEnc : enc);

	updateEncodingState(isDefault);
	}

	private void updateValidState() {
	if (!isEncodingValid()) {
	setErrorMessage(IDEWorkbenchMessages.getString("WorkbenchPreference.unsupportedEncoding")); //$NON-NLS-1$
	setValid(false);
	} else {
	setErrorMessage(null);
	setValid(true);
	}
	}

	private boolean isEncodingValid() {
	return defaultEncodingButton.getSelection() \|\|
	isValidEncoding(encodingCombo.getText());
	}

	private boolean isValidEncoding(String enc) {
	try {
	new String(new byte[0], enc);
	return true;
	} catch (UnsupportedEncodingException e) {
	return false;
	}
	}

	private void updateEncodingState(boolean useDefault) {
	defaultEncodingButton.setSelection(useDefault);
	otherEncodingButton.setSelection(!useDefault);
	encodingCombo.setEnabled(!useDefault);
	updateValidState();
	}

	/**
	* Create a composite that contains buttons for selecting the
	* preference opening new project selections.
	*/
	private void createProjectPerspectiveGroup(Composite composite) {

	Composite projectComposite = new Composite(composite, SWT.NONE);
	projectComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
	projectComposite.setFont(composite.getFont());

	String[][] namesAndValues = {
	{PSPM_ALWAYS_TEXT, IDEInternalPreferences.PSPM_ALWAYS},
	{PSPM_NEVER_TEXT, IDEInternalPreferences.PSPM_NEVER},
	{PSPM_PROMPT_TEXT, IDEInternalPreferences.PSPM_PROMPT}
	};
	projectSwitchField = new RadioGroupFieldEditor(
	IDEInternalPreferences.PROJECT_SWITCH_PERSP_MODE,
	PROJECT_SWITCH_PERSP_MODE_TITLE,
	namesAndValues.length,
	namesAndValues,
	projectComposite,
	true);
	projectSwitchField.setPreferenceStore(getPreferenceStore());
	projectSwitchField.setPreferencePage(this);
	projectSwitchField.load();
	}

	/**
	* Utility method that creates a radio button instance
	* and sets the default layout data.
	*
	* @param parent the parent for the new button
	* @param label the label for the new button
	* @return the newly-created button
	*/
	protected static Button createRadioButton(Composite parent, String label) {
	Button button = new Button(parent, SWT.RADIO \| SWT.LEFT);
	button.setText(label);
	button.setFont(parent.getFont());
	return button;
	}

	/**
	* Utility method that creates a combo box
	*
	* @param parent the parent for the new label
	* @return the new widget
	*/
	protected static Combo createCombo(Composite parent) {
	Combo combo = new Combo(parent, SWT.READ_ONLY);
	GridData data = new GridData(GridData.FILL_HORIZONTAL);
	data.widthHint = IDialogConstants.ENTRY_FIELD_WIDTH;
	combo.setLayoutData(data);
	combo.setFont(parent.getFont());
	return combo;
	}

	/**
	* Utility method that creates a label instance
	* and sets the default layout data.
	*
	* @param parent the parent for the new label
	* @param text the text for the new label
	* @return the new label
	*/
	protected static Label createLabel(Composite parent, String text) {
	Label label = new Label(parent, SWT.LEFT);
	label.setText(text);
	label.setFont(parent.getFont());
	GridData data = new GridData();
	data.horizontalSpan = 1;
	data.horizontalAlignment = GridData.FILL;
	label.setLayoutData(data);
	return label;
	}

	/**
	* Creates a tab of one horizontal spans.
	*
	* @param parent the parent in which the tab should be created
	*/
	protected static void createSpace(Composite parent) {
	Label vfiller = new Label(parent, SWT.LEFT);
	GridData gridData = new GridData();
	gridData = new GridData();
	gridData.horizontalAlignment = GridData.BEGINNING;
	gridData.grabExcessHorizontalSpace = false;
	gridData.verticalAlignment = GridData.CENTER;
	gridData.grabExcessVerticalSpace = false;
	vfiller.setLayoutData(gridData);
	}

	/**
	* Returns preference store that belongs to the our plugin.
	*
	* @return the preference store for this plugin
	*/
	protected IPreferenceStore doGetPreferenceStore() {
	return IDEWorkbenchPlugin.getDefault().getPreferenceStore();
	}

	/**
	* @see IWorkbenchPreferencePage
	*/
	public void init(IWorkbench aWorkbench) {
	// do nothing
	}

	/**
	* The default button has been pressed.
	*/
	protected void performDefaults() {
	updateEncodingState(true);

	// core holds onto this preference.
	boolean autoBuild = ResourcesPlugin.getPlugin().getPluginPreferences().getDefaultBoolean(ResourcesPlugin.PREF_AUTO_BUILDING);
	autoBuildButton.setSelection(autoBuild);

	IPreferenceStore store = getPreferenceStore();
	autoSaveAllButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD));
	refreshButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP));
	exitPromptButton.setSelection(store.getDefaultBoolean(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW));
	showTasks.setSelection(store.getBoolean(IDEInternalPreferences.SHOW_TASKS_ON_BUILD));
	saveInterval.loadDefault();

	projectSwitchField.loadDefault();

	super.performDefaults();
	}

	/**
	* The user has pressed Ok. Store/apply this page's values appropriately.
	*/
	public boolean performOk() {
	// set the workspace auto-build flag
	IWorkspaceDescription description = ResourcesPlugin.getWorkspace().getDescription();
	if (autoBuildButton.getSelection() != ResourcesPlugin.getWorkspace().isAutoBuilding()) {
	try {
	description.setAutoBuilding(autoBuildButton.getSelection());
	ResourcesPlugin.getWorkspace().setDescription(description);
	} catch (CoreException e) {
	IDEWorkbenchPlugin.log("Error changing auto build workspace setting.", e.getStatus()); //$NON-NLS-1$
	}
	}

	// set the workspace text file encoding
	Preferences resourcePrefs = ResourcesPlugin.getPlugin().getPluginPreferences();
	if (defaultEncodingButton.getSelection()) {
	resourcePrefs.setToDefault(ResourcesPlugin.PREF_ENCODING);
	}
	else {
	String enc = encodingCombo.getText();
	resourcePrefs.setValue(ResourcesPlugin.PREF_ENCODING, enc);
	}
	ResourcesPlugin.getPlugin().savePluginPreferences();

	IPreferenceStore store = getPreferenceStore();

	// store the save all prior to build setting
	store.setValue(IDEInternalPreferences.SAVE_ALL_BEFORE_BUILD, autoSaveAllButton.getSelection());

	// store the refresh workspace on startup setting
	store.setValue(IDEInternalPreferences.REFRESH_WORKSPACE_ON_STARTUP, refreshButton.getSelection());

	// store the exit prompt on last window close setting
	store.setValue(IDEInternalPreferences.EXIT_PROMPT_ON_CLOSE_LAST_WINDOW, exitPromptButton.getSelection());

	// store the preference for bringing task view to front on build
	store.setValue(IDEInternalPreferences.SHOW_TASKS_ON_BUILD, showTasks.getSelection());

	// store the workspace save interval
	// @issue we should drop our preference constant and let clients use core's pref. ours is not up-to-date anyway if someone changes this interval directly thru core api.
	long oldSaveInterval = description.getSnapshotInterval() / 60000;
	long newSaveInterval = new Long(saveInterval.getStringValue()).longValue();
	if (oldSaveInterval != newSaveInterval) {
	try {
	description.setSnapshotInterval(newSaveInterval * 60000);
	ResourcesPlugin.getWorkspace().setDescription(description);
	store.firePropertyChangeEvent(IDEInternalPreferences.SAVE_INTERVAL, new Integer((int)oldSaveInterval), new Integer((int)newSaveInterval));
	} catch (CoreException e) {
	IDEWorkbenchPlugin.log("Error changing save interval preference", e.getStatus()); //$NON-NLS-1$
	}
	}

	// store the open new project perspective settings
	projectSwitchField.store();

	IDEWorkbenchPlugin.getDefault().savePluginPreferences();
	return true;
	}
	}