org.eclipse.ui.editors/src/org/eclipse/ui/internal/editors/text/AccessibilityPreferencePage.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2015 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
  *******************************************************************************/
 package org.eclipse.ui.internal.editors.text;

 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Set;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 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.Label;
 import org.eclipse.swt.widgets.Text;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.IStatus;

 import org.eclipse.jface.dialogs.Dialog;
 import org.eclipse.jface.dialogs.DialogPage;
 import org.eclipse.jface.dialogs.IMessageProvider;
 import org.eclipse.jface.preference.PreferencePage;

 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.IWorkbenchPreferencePage;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.internal.editors.text.AccessibilityPreferencePage.EnumeratedDomain.EnumValue;
 import org.eclipse.ui.internal.editors.text.OverlayPreferenceStore.OverlayKey;

 import org.eclipse.ui.texteditor.AbstractDecoratedTextEditorPreferenceConstants;

 import org.eclipse.ui.editors.text.ITextEditorHelpContextIds;


 /**
  * The preference page for setting the editor options.
  * <p>
  * This class is internal and not intended to be used by clients.</p>
  *
  * @since 2.1
  */
 public class AccessibilityPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {


 	private abstract class Initializer {

 		protected final Preference fPreference;

 		protected Initializer(Preference preference) {
 			fPreference= preference;
 		}

 		public abstract void initialize();
 	}


 	public final class InitializerFactory {
 		private class TextInitializer extends Initializer {
 			private final Text fText;

 			public TextInitializer(Preference preference, Text control) {
 				super(preference);
 				fText= control;
 			}
 			@Override
 			public void initialize() {
 				String value= fOverlayStore.getString(fPreference.getKey());
 				fText.setText(value);
 			}
 		}

 		private class CheckboxInitializer extends Initializer {
 			private final Button fControl;

 			public CheckboxInitializer(Preference preference, Button control) {
 				super(preference);
 				fControl= control;
 			}
 			@Override
 			public void initialize() {
 				boolean value= fOverlayStore.getBoolean(fPreference.getKey());
 				fControl.setSelection(value);
 			}
 		}

 		private class ComboInitializer extends Initializer {
 			private final Combo fControl;
 			private final EnumeratedDomain fDomain;

 			public ComboInitializer(Preference preference, Combo control, EnumeratedDomain domain) {
 				super(preference);
 				fControl= control;
 				fDomain= domain;
 			}
 			@Override
 			public void initialize() {
 				int value= fOverlayStore.getInt(fPreference.getKey());
 				EnumValue enumValue= fDomain.getValueByInteger(value);
 				if (enumValue != null) {
 					int index= fDomain.getIndex(enumValue);
 					if (index >= 0)
 						fControl.select(index);
 				}
 			}
 		}

 		public Initializer create(Preference preference, Text control) {
 			return new TextInitializer(preference, control);
 		}

 		public Initializer create(Preference preference, Button control) {
 			return new CheckboxInitializer(preference, control);
 		}

 		public Initializer create(Preference preference, Combo control, EnumeratedDomain domain) {
 			return new ComboInitializer(preference, control, domain);
 		}
 	}


 	abstract static class Domain {
 		public abstract IStatus validate(Object value);
 		protected int parseInteger(Object val) throws NumberFormatException {
 			if (val instanceof Integer)
 				return ((Integer) val).intValue();

 			if (val instanceof String)
 				return Integer.parseInt((String) val);

 			throw new NumberFormatException(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(val)));
 		}
 	}

 	static class IntegerDomain extends Domain {
 		private final int fMax;
 		private final int fMin;
 		public IntegerDomain(int min, int max) {
 			Assert.isLegal(max >= min);
 			fMax= max;
 			fMin= min;
 		}

 		@Override
 		public IStatus validate(Object value) {
 			StatusInfo status= new StatusInfo();
 			if (value instanceof String && ((String)value).length() == 0) {
 				status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
 				return status;
 			}

 			try {
 				int integer= parseInteger(value);
 				if (!rangeCheck(integer))
 					status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(integer)));
 			} catch (NumberFormatException e) {
 					status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
 			}
 			return status;
 		}

 		protected boolean rangeCheck(int i) {
 			return (i >= fMin && i <= fMax);
 		}

 	}

 	static class EnumeratedDomain extends Domain {
 		public final static class EnumValue {
 			private final int fValue;
 			private final String fName;
 			public EnumValue(int value) {
 				this(value, null);
 			}
 			public EnumValue(int value, String name) {
 				fValue= value;
 				fName= name;
 			}
 			public String getLabel() {
 				return fName == null ? String.valueOf(fValue) : fName;
 			}
 			public int getIntValue() {
 				return fValue;
 			}
 			@Override
 			public final int hashCode() {
 				return getIntValue();
 			}
 			@Override
 			public boolean equals(Object obj) {
 				if (obj instanceof EnumValue) {
 					return ((EnumValue) obj).getIntValue() == fValue;
 				}
 				return false;
 			}
 		}

 		private final java.util.List<EnumValue> fItems= new ArrayList<>();
 		private final Set<EnumValue> fValueSet= new HashSet<>();

 		public void addValue(EnumValue val) {
 			if (fValueSet.contains(val))
 				fItems.remove(val);
 			fItems.add(val);
 			fValueSet.add(val);
 		}

 		public int getIndex(EnumValue enumValue) {
 			int i= 0;
 			for (Iterator<EnumValue> it= fItems.iterator(); it.hasNext();) {
 				EnumValue ev= it.next();
 				if (ev.equals(enumValue))
 					return i;
 				i++;
 			}
 			return -1;
 		}

 		public EnumValue getValueByIndex (int index) {
 			if (index >= 0 && fItems.size() > index)
 				return fItems.get(index);
 			return null;
 		}

 		public EnumValue getValueByInteger(int intValue) {
 			for (Iterator<EnumValue> it= fItems.iterator(); it.hasNext();) {
 				EnumValue e= it.next();
 				if (e.getIntValue() == intValue)
 					return e;
 			}
 			return null;
 		}

 		public void addValue(int val) {
 			addValue(new EnumValue(val));
 		}

 		public void addRange(int from, int to) {
 			while (from <= to)
 				addValue(from++);
 		}

 		@Override
 		public IStatus validate(Object value) {
 			StatusInfo status= new StatusInfo();
 			if (value instanceof String && ((String)value).length() == 0) {
 				status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
 				return status;
 			}

 			try {
 				EnumValue e= parseEnumValue(value);
 				if (!fValueSet.contains(e))
 					status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidRange, new String[] {getValueByIndex(0).getLabel(), getValueByIndex(fItems.size() - 1).getLabel()}));
 			} catch (NumberFormatException e) {
 				status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
 			}

 			return status;
 		}

 		private EnumValue parseEnumValue(Object value) {
 			if (value instanceof EnumValue)
 				return (EnumValue) value;
 			int integer= parseInteger(value);
 			return getValueByInteger(integer);
 		}
 	}

 	static class BooleanDomain extends Domain {
 		@Override
 		public IStatus validate(Object value) {
 			StatusInfo status= new StatusInfo();
 			if (value instanceof String && ((String)value).length() == 0) {
 				status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
 				return status;
 			}

 			try {
 				parseBoolean(value);
 			} catch (NumberFormatException e) {
 				status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
 			}

 			return status;
 		}

 		private boolean parseBoolean(Object value) throws NumberFormatException {
 			if (value instanceof Boolean)
 				return ((Boolean) value).booleanValue();

 			if (value instanceof String) {
 				if (Boolean.TRUE.toString().equalsIgnoreCase((String) value))
 					return true;
 				if (Boolean.FALSE.toString().equalsIgnoreCase((String) value))
 					return false;
 			}

 			throw new NumberFormatException(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
 		}
 	}

 	private static class Preference {
 		private String fKey;
 		private String fName;
 		private String fDescription; // for tooltips

 		public Preference(String key, String name, String description) {
 			Assert.isNotNull(key);
 			Assert.isNotNull(name);
 			fKey= key;
 			fName= name;
 			fDescription= description;
 		}
 		public final String getKey() {
 			return fKey;
 		}
 		public final String getName() {
 			return fName;
 		}
 		public final String getDescription() {
 			return fDescription;
 		}
 	}

 	private OverlayPreferenceStore fOverlayStore;

 	/**
 	 * Tells whether the fields are initialized.
 	 * @since 3.0
 	 */
 	private boolean fFieldsInitialized= false;

 	private java.util.List<Initializer> fInitializers= new ArrayList<>();

 	private InitializerFactory fInitializerFactory= new InitializerFactory();

 	private Control fContents;
 	private ArrayList<SelectionListener> fMasterSlaveListeners= new ArrayList<>();


 	public AccessibilityPreferencePage() {
 		setDescription(TextEditorMessages.AccessibilityPreferencePage_accessibility_title);
 		setPreferenceStore(EditorsPlugin.getDefault().getPreferenceStore());

 		fOverlayStore= createOverlayStore();
 	}


 	@Override
 	protected Label createDescriptionLabel(Composite parent) {
 		return null; // no description for new look
 	}

 	private OverlayPreferenceStore createOverlayStore() {

 		ArrayList<OverlayKey> overlayKeys= new ArrayList<>();

 		overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_USE_CUSTOM_CARETS));
 		overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_WIDE_CARET));
 		overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.QUICK_DIFF_CHARACTER_MODE));
 		overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.USE_SATURATED_COLORS_IN_OVERVIEW_RULER));

 		OverlayPreferenceStore.OverlayKey[] keys= new OverlayPreferenceStore.OverlayKey[overlayKeys.size()];
 		overlayKeys.toArray(keys);
 		return new OverlayPreferenceStore(getPreferenceStore(), keys);
 	}

 	@Override
 	public void init(IWorkbench workbench) {
 	}

 	@Override
 	public void createControl(Composite parent) {
 		super.createControl(parent);
 		PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), ITextEditorHelpContextIds.ACCESSIBILITY_PREFERENCE_PAGE);
 	}

 	private Control createAppearancePage(Composite parent) {


 		Composite appearanceComposite= new Composite(parent, SWT.NONE);
 		GridLayout layout= new GridLayout();
 		layout.numColumns= 2;
 		layout.marginHeight= 0;
 		layout.marginWidth= 0;

 		appearanceComposite.setLayout(layout);

 		String label= TextEditorMessages.TextEditorPreferencePage_accessibility_disableCustomCarets;
 		Preference customCarets= new Preference(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_USE_CUSTOM_CARETS, label, null);
 		Button master= addCheckBox(appearanceComposite, customCarets, new BooleanDomain(), 0);

 		label= TextEditorMessages.TextEditorPreferencePage_accessibility_wideCaret;
 		Preference wideCaret= new Preference(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_WIDE_CARET, label, null);
 		Button slave= addCheckBox(appearanceComposite, wideCaret, new BooleanDomain(), 0);
 		createDependency(master, customCarets, new Control[] { slave });

 		label= TextEditorMessages.QuickDiffConfigurationBlock_characterMode;
 		Preference quickDiffTextMode= new Preference(AbstractDecoratedTextEditorPreferenceConstants.QUICK_DIFF_CHARACTER_MODE, label, null);
 		addCheckBox(appearanceComposite, quickDiffTextMode, new BooleanDomain(), 0);

 		label= TextEditorMessages.TextEditorPreferencePage_accessibility_useSaturatedColorsInOverviewRuler;
 		Preference useSaturatedColors= new Preference(AbstractDecoratedTextEditorPreferenceConstants.USE_SATURATED_COLORS_IN_OVERVIEW_RULER, label, null);
 		addCheckBox(appearanceComposite, useSaturatedColors, new BooleanDomain(), 0);

 		return appearanceComposite;
 	}

 	@Override
 	protected Control createContents(Composite parent) {

 		fOverlayStore.load();
 		fOverlayStore.start();

 		fContents= createAppearancePage(parent);

 		initialize();
 		Dialog.applyDialogFont(fContents);
 		return fContents;
 	}

 	private void initialize() {
 		initializeFields();
 	}

 	private void initializeFields() {

 		for (Iterator<Initializer> it= fInitializers.iterator(); it.hasNext();) {
 			Initializer initializer= it.next();
 			initializer.initialize();
 		}

 		fFieldsInitialized= true;

 		updateStatus(new StatusInfo());

 	}

 	@Override
 	public boolean performOk() {
 		fOverlayStore.propagate();
 		return true;
 	}

 	@Override
 	protected void performDefaults() {

 		fOverlayStore.loadDefaults();

 		initializeFields();

 		for (Iterator<SelectionListener> iterator= fMasterSlaveListeners.iterator(); iterator.hasNext();) {
 			SelectionListener listener= iterator.next();
 			listener.widgetSelected(null);
 		}

 		super.performDefaults();
 	}

 	@Override
 	public void dispose() {

 		if (fOverlayStore != null) {
 			fOverlayStore.stop();
 			fOverlayStore= null;
 		}

 		super.dispose();
 	}


 	private Button addCheckBox(Composite composite, final Preference preference, final Domain domain, int indentation) {
 		final Button checkBox= new Button(composite, SWT.CHECK);
 		checkBox.setText(preference.getName());
 		checkBox.setToolTipText(preference.getDescription());

 		GridData gd= new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING);
 		gd.horizontalIndent= indentation;
 		gd.horizontalSpan= 2;
 		checkBox.setLayoutData(gd);
 		checkBox.addSelectionListener(new SelectionAdapter() {
 			@Override
 			public void widgetSelected(SelectionEvent e) {
 				boolean value= checkBox.getSelection();
 				IStatus status= domain.validate(Boolean.valueOf(value));
 				if (!status.matches(IStatus.ERROR))
 					fOverlayStore.setValue(preference.getKey(), value);
 				updateStatus(status);
 			}
 		});

 		fInitializers.add(fInitializerFactory.create(preference, checkBox));

 		return checkBox;
 	}

 	private void createDependency(final Button master, Preference preference, final Control[] slaves) {
 		indent(slaves[0]);

 		boolean masterState= fOverlayStore.getBoolean(preference.getKey());
 		for (int i= 0; i < slaves.length; i++) {
 			slaves[i].setEnabled(masterState);
 		}

 		SelectionListener listener= new SelectionListener() {
 			@Override
 			public void widgetSelected(SelectionEvent e) {
 				boolean state= master.getSelection();
 				for (int i= 0; i < slaves.length; i++) {
 					slaves[i].setEnabled(state);
 				}
 			}

 			@Override
 			public void widgetDefaultSelected(SelectionEvent e) {}
 		};
 		master.addSelectionListener(listener);
 		fMasterSlaveListeners.add(listener);
 	}

 	private static void indent(Control control) {
 		GridData gridData= new GridData();
 		gridData.horizontalIndent= 20;
 		control.setLayoutData(gridData);
 	}

 	void updateStatus(IStatus status) {
 		if (!fFieldsInitialized)
 			return;

 		setValid(!status.matches(IStatus.ERROR));
 		applyToStatusLine(this, status);
 	}

 	/**
 	 * Applies the status to the status line of a dialog page.
 	 *
 	 * @param page the dialog page
 	 * @param status the status
 	 */
 	public void applyToStatusLine(DialogPage page, IStatus status) {
 		String message= status.getMessage();
 		switch (status.getSeverity()) {
 			case IStatus.OK:
 				page.setMessage(message, IMessageProvider.NONE);
 				page.setErrorMessage(null);
 				break;
 			case IStatus.WARNING:
 				page.setMessage(message, IMessageProvider.WARNING);
 				page.setErrorMessage(null);
 				break;
 			case IStatus.INFO:
 				page.setMessage(message, IMessageProvider.INFORMATION);
 				page.setErrorMessage(null);
 				break;
 			default:
 				if (message.length() == 0) {
 					message= null;
 				}
 				page.setMessage(null);
 				page.setErrorMessage(message);
 				break;
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2015 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
	*******************************************************************************/
	package org.eclipse.ui.internal.editors.text;

	import java.util.ArrayList;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.Set;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.events.SelectionListener;
	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.Label;
	import org.eclipse.swt.widgets.Text;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.core.runtime.IStatus;

	import org.eclipse.jface.dialogs.Dialog;
	import org.eclipse.jface.dialogs.DialogPage;
	import org.eclipse.jface.dialogs.IMessageProvider;
	import org.eclipse.jface.preference.PreferencePage;

	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.IWorkbenchPreferencePage;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.internal.editors.text.AccessibilityPreferencePage.EnumeratedDomain.EnumValue;
	import org.eclipse.ui.internal.editors.text.OverlayPreferenceStore.OverlayKey;

	import org.eclipse.ui.texteditor.AbstractDecoratedTextEditorPreferenceConstants;

	import org.eclipse.ui.editors.text.ITextEditorHelpContextIds;


	/**
	* The preference page for setting the editor options.
	* <p>
	* This class is internal and not intended to be used by clients.</p>
	*
	* @since 2.1
	*/
	public class AccessibilityPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {


	private abstract class Initializer {

	protected final Preference fPreference;

	protected Initializer(Preference preference) {
	fPreference= preference;
	}

	public abstract void initialize();
	}


	public final class InitializerFactory {
	private class TextInitializer extends Initializer {
	private final Text fText;

	public TextInitializer(Preference preference, Text control) {
	super(preference);
	fText= control;
	}
	@Override
	public void initialize() {
	String value= fOverlayStore.getString(fPreference.getKey());
	fText.setText(value);
	}
	}

	private class CheckboxInitializer extends Initializer {
	private final Button fControl;

	public CheckboxInitializer(Preference preference, Button control) {
	super(preference);
	fControl= control;
	}
	@Override
	public void initialize() {
	boolean value= fOverlayStore.getBoolean(fPreference.getKey());
	fControl.setSelection(value);
	}
	}

	private class ComboInitializer extends Initializer {
	private final Combo fControl;
	private final EnumeratedDomain fDomain;

	public ComboInitializer(Preference preference, Combo control, EnumeratedDomain domain) {
	super(preference);
	fControl= control;
	fDomain= domain;
	}
	@Override
	public void initialize() {
	int value= fOverlayStore.getInt(fPreference.getKey());
	EnumValue enumValue= fDomain.getValueByInteger(value);
	if (enumValue != null) {
	int index= fDomain.getIndex(enumValue);
	if (index >= 0)
	fControl.select(index);
	}
	}
	}

	public Initializer create(Preference preference, Text control) {
	return new TextInitializer(preference, control);
	}

	public Initializer create(Preference preference, Button control) {
	return new CheckboxInitializer(preference, control);
	}

	public Initializer create(Preference preference, Combo control, EnumeratedDomain domain) {
	return new ComboInitializer(preference, control, domain);
	}
	}


	abstract static class Domain {
	public abstract IStatus validate(Object value);
	protected int parseInteger(Object val) throws NumberFormatException {
	if (val instanceof Integer)
	return ((Integer) val).intValue();

	if (val instanceof String)
	return Integer.parseInt((String) val);

	throw new NumberFormatException(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(val)));
	}
	}

	static class IntegerDomain extends Domain {
	private final int fMax;
	private final int fMin;
	public IntegerDomain(int min, int max) {
	Assert.isLegal(max >= min);
	fMax= max;
	fMin= min;
	}

	@Override
	public IStatus validate(Object value) {
	StatusInfo status= new StatusInfo();
	if (value instanceof String && ((String)value).length() == 0) {
	status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
	return status;
	}

	try {
	int integer= parseInteger(value);
	if (!rangeCheck(integer))
	status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(integer)));
	} catch (NumberFormatException e) {
	status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
	}
	return status;
	}

	protected boolean rangeCheck(int i) {
	return (i >= fMin && i <= fMax);
	}

	}

	static class EnumeratedDomain extends Domain {
	public final static class EnumValue {
	private final int fValue;
	private final String fName;
	public EnumValue(int value) {
	this(value, null);
	}
	public EnumValue(int value, String name) {
	fValue= value;
	fName= name;
	}
	public String getLabel() {
	return fName == null ? String.valueOf(fValue) : fName;
	}
	public int getIntValue() {
	return fValue;
	}
	@Override
	public final int hashCode() {
	return getIntValue();
	}
	@Override
	public boolean equals(Object obj) {
	if (obj instanceof EnumValue) {
	return ((EnumValue) obj).getIntValue() == fValue;
	}
	return false;
	}
	}

	private final java.util.List<EnumValue> fItems= new ArrayList<>();
	private final Set<EnumValue> fValueSet= new HashSet<>();

	public void addValue(EnumValue val) {
	if (fValueSet.contains(val))
	fItems.remove(val);
	fItems.add(val);
	fValueSet.add(val);
	}

	public int getIndex(EnumValue enumValue) {
	int i= 0;
	for (Iterator<EnumValue> it= fItems.iterator(); it.hasNext();) {
	EnumValue ev= it.next();
	if (ev.equals(enumValue))
	return i;
	i++;
	}
	return -1;
	}

	public EnumValue getValueByIndex (int index) {
	if (index >= 0 && fItems.size() > index)
	return fItems.get(index);
	return null;
	}

	public EnumValue getValueByInteger(int intValue) {
	for (Iterator<EnumValue> it= fItems.iterator(); it.hasNext();) {
	EnumValue e= it.next();
	if (e.getIntValue() == intValue)
	return e;
	}
	return null;
	}

	public void addValue(int val) {
	addValue(new EnumValue(val));
	}

	public void addRange(int from, int to) {
	while (from <= to)
	addValue(from++);
	}

	@Override
	public IStatus validate(Object value) {
	StatusInfo status= new StatusInfo();
	if (value instanceof String && ((String)value).length() == 0) {
	status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
	return status;
	}

	try {
	EnumValue e= parseEnumValue(value);
	if (!fValueSet.contains(e))
	status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidRange, new String[] {getValueByIndex(0).getLabel(), getValueByIndex(fItems.size() - 1).getLabel()}));
	} catch (NumberFormatException e) {
	status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
	}

	return status;
	}

	private EnumValue parseEnumValue(Object value) {
	if (value instanceof EnumValue)
	return (EnumValue) value;
	int integer= parseInteger(value);
	return getValueByInteger(integer);
	}
	}

	static class BooleanDomain extends Domain {
	@Override
	public IStatus validate(Object value) {
	StatusInfo status= new StatusInfo();
	if (value instanceof String && ((String)value).length() == 0) {
	status.setError(TextEditorMessages.TextEditorPreferencePage_emptyInput);
	return status;
	}

	try {
	parseBoolean(value);
	} catch (NumberFormatException e) {
	status.setError(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
	}

	return status;
	}

	private boolean parseBoolean(Object value) throws NumberFormatException {
	if (value instanceof Boolean)
	return ((Boolean) value).booleanValue();

	if (value instanceof String) {
	if (Boolean.TRUE.toString().equalsIgnoreCase((String) value))
	return true;
	if (Boolean.FALSE.toString().equalsIgnoreCase((String) value))
	return false;
	}

	throw new NumberFormatException(NLSUtility.format(TextEditorMessages.TextEditorPreferencePage_invalidInput, String.valueOf(value)));
	}
	}

	private static class Preference {
	private String fKey;
	private String fName;
	private String fDescription; // for tooltips

	public Preference(String key, String name, String description) {
	Assert.isNotNull(key);
	Assert.isNotNull(name);
	fKey= key;
	fName= name;
	fDescription= description;
	}
	public final String getKey() {
	return fKey;
	}
	public final String getName() {
	return fName;
	}
	public final String getDescription() {
	return fDescription;
	}
	}

	private OverlayPreferenceStore fOverlayStore;

	/**
	* Tells whether the fields are initialized.
	* @since 3.0
	*/
	private boolean fFieldsInitialized= false;

	private java.util.List<Initializer> fInitializers= new ArrayList<>();

	private InitializerFactory fInitializerFactory= new InitializerFactory();

	private Control fContents;
	private ArrayList<SelectionListener> fMasterSlaveListeners= new ArrayList<>();


	public AccessibilityPreferencePage() {
	setDescription(TextEditorMessages.AccessibilityPreferencePage_accessibility_title);
	setPreferenceStore(EditorsPlugin.getDefault().getPreferenceStore());

	fOverlayStore= createOverlayStore();
	}


	@Override
	protected Label createDescriptionLabel(Composite parent) {
	return null; // no description for new look
	}

	private OverlayPreferenceStore createOverlayStore() {

	ArrayList<OverlayKey> overlayKeys= new ArrayList<>();

	overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_USE_CUSTOM_CARETS));
	overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_WIDE_CARET));
	overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.QUICK_DIFF_CHARACTER_MODE));
	overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, AbstractDecoratedTextEditorPreferenceConstants.USE_SATURATED_COLORS_IN_OVERVIEW_RULER));

	OverlayPreferenceStore.OverlayKey[] keys= new OverlayPreferenceStore.OverlayKey[overlayKeys.size()];
	overlayKeys.toArray(keys);
	return new OverlayPreferenceStore(getPreferenceStore(), keys);
	}

	@Override
	public void init(IWorkbench workbench) {
	}

	@Override
	public void createControl(Composite parent) {
	super.createControl(parent);
	PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), ITextEditorHelpContextIds.ACCESSIBILITY_PREFERENCE_PAGE);
	}

	private Control createAppearancePage(Composite parent) {


	Composite appearanceComposite= new Composite(parent, SWT.NONE);
	GridLayout layout= new GridLayout();
	layout.numColumns= 2;
	layout.marginHeight= 0;
	layout.marginWidth= 0;

	appearanceComposite.setLayout(layout);

	String label= TextEditorMessages.TextEditorPreferencePage_accessibility_disableCustomCarets;
	Preference customCarets= new Preference(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_USE_CUSTOM_CARETS, label, null);
	Button master= addCheckBox(appearanceComposite, customCarets, new BooleanDomain(), 0);

	label= TextEditorMessages.TextEditorPreferencePage_accessibility_wideCaret;
	Preference wideCaret= new Preference(AbstractDecoratedTextEditorPreferenceConstants.EDITOR_WIDE_CARET, label, null);
	Button slave= addCheckBox(appearanceComposite, wideCaret, new BooleanDomain(), 0);
	createDependency(master, customCarets, new Control[] { slave });

	label= TextEditorMessages.QuickDiffConfigurationBlock_characterMode;
	Preference quickDiffTextMode= new Preference(AbstractDecoratedTextEditorPreferenceConstants.QUICK_DIFF_CHARACTER_MODE, label, null);
	addCheckBox(appearanceComposite, quickDiffTextMode, new BooleanDomain(), 0);

	label= TextEditorMessages.TextEditorPreferencePage_accessibility_useSaturatedColorsInOverviewRuler;
	Preference useSaturatedColors= new Preference(AbstractDecoratedTextEditorPreferenceConstants.USE_SATURATED_COLORS_IN_OVERVIEW_RULER, label, null);
	addCheckBox(appearanceComposite, useSaturatedColors, new BooleanDomain(), 0);

	return appearanceComposite;
	}

	@Override
	protected Control createContents(Composite parent) {

	fOverlayStore.load();
	fOverlayStore.start();

	fContents= createAppearancePage(parent);

	initialize();
	Dialog.applyDialogFont(fContents);
	return fContents;
	}

	private void initialize() {
	initializeFields();
	}

	private void initializeFields() {

	for (Iterator<Initializer> it= fInitializers.iterator(); it.hasNext();) {
	Initializer initializer= it.next();
	initializer.initialize();
	}

	fFieldsInitialized= true;

	updateStatus(new StatusInfo());

	}

	@Override
	public boolean performOk() {
	fOverlayStore.propagate();
	return true;
	}

	@Override
	protected void performDefaults() {

	fOverlayStore.loadDefaults();

	initializeFields();

	for (Iterator<SelectionListener> iterator= fMasterSlaveListeners.iterator(); iterator.hasNext();) {
	SelectionListener listener= iterator.next();
	listener.widgetSelected(null);
	}

	super.performDefaults();
	}

	@Override
	public void dispose() {

	if (fOverlayStore != null) {
	fOverlayStore.stop();
	fOverlayStore= null;
	}

	super.dispose();
	}



	private Button addCheckBox(Composite composite, final Preference preference, final Domain domain, int indentation) {
	final Button checkBox= new Button(composite, SWT.CHECK);
	checkBox.setText(preference.getName());
	checkBox.setToolTipText(preference.getDescription());

	GridData gd= new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING);
	gd.horizontalIndent= indentation;
	gd.horizontalSpan= 2;
	checkBox.setLayoutData(gd);
	checkBox.addSelectionListener(new SelectionAdapter() {
	@Override
	public void widgetSelected(SelectionEvent e) {
	boolean value= checkBox.getSelection();
	IStatus status= domain.validate(Boolean.valueOf(value));
	if (!status.matches(IStatus.ERROR))
	fOverlayStore.setValue(preference.getKey(), value);
	updateStatus(status);
	}
	});

	fInitializers.add(fInitializerFactory.create(preference, checkBox));

	return checkBox;
	}

	private void createDependency(final Button master, Preference preference, final Control[] slaves) {
	indent(slaves[0]);

	boolean masterState= fOverlayStore.getBoolean(preference.getKey());
	for (int i= 0; i < slaves.length; i++) {
	slaves[i].setEnabled(masterState);
	}

	SelectionListener listener= new SelectionListener() {
	@Override
	public void widgetSelected(SelectionEvent e) {
	boolean state= master.getSelection();
	for (int i= 0; i < slaves.length; i++) {
	slaves[i].setEnabled(state);
	}
	}

	@Override
	public void widgetDefaultSelected(SelectionEvent e) {}
	};
	master.addSelectionListener(listener);
	fMasterSlaveListeners.add(listener);
	}

	private static void indent(Control control) {
	GridData gridData= new GridData();
	gridData.horizontalIndent= 20;
	control.setLayoutData(gridData);
	}

	void updateStatus(IStatus status) {
	if (!fFieldsInitialized)
	return;

	setValid(!status.matches(IStatus.ERROR));
	applyToStatusLine(this, status);
	}

	/**
	* Applies the status to the status line of a dialog page.
	*
	* @param page the dialog page
	* @param status the status
	*/
	public void applyToStatusLine(DialogPage page, IStatus status) {
	String message= status.getMessage();
	switch (status.getSeverity()) {
	case IStatus.OK:
	page.setMessage(message, IMessageProvider.NONE);
	page.setErrorMessage(null);
	break;
	case IStatus.WARNING:
	page.setMessage(message, IMessageProvider.WARNING);
	page.setErrorMessage(null);
	break;
	case IStatus.INFO:
	page.setMessage(message, IMessageProvider.INFORMATION);
	page.setErrorMessage(null);
	break;
	default:
	if (message.length() == 0) {
	message= null;
	}
	page.setMessage(null);
	page.setErrorMessage(message);
	break;
	}
	}
	}