org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/LaunchConfigurationTypesPreferencePage.java - gerrit/platform/eclipse.platform.debug - Git at Google

 package org.eclipse.debug.internal.ui;

 /*
  * (c) Copyright IBM Corp. 2000, 2001.
  * All Rights Reserved.
  */

 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;

 import org.eclipse.debug.core.DebugPlugin;
 import org.eclipse.debug.core.ILaunchConfigurationType;
 import org.eclipse.debug.core.ILaunchManager;
 import org.eclipse.debug.ui.DebugUITools;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.IStructuredContentProvider;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.ITableLabelProvider;
 import org.eclipse.jface.viewers.LabelProvider;
 import org.eclipse.jface.viewers.SelectionChangedEvent;
 import org.eclipse.jface.viewers.TableViewer;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.ui.IFileEditorMapping;
 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.IWorkbenchPreferencePage;
 import org.eclipse.ui.internal.WorkbenchPlugin;

 public class LaunchConfigurationTypesPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {

 	// UI widgets
 	private Label fFileTypeLabel;
 	private TableViewer fFileTypeTableViewer;
 	private Label fConfigTypeLabel;
 	private TableViewer fConfigTypeTableViewer;
 	private Button fDefaultButton;

 	// Local mapping of file extensions to default launch configs.  It is necessary to keep a local
 	// copy of this in this class so that the user can 'Cancel' out of any changes they make in this
 	// preference page.
 	private Map fDefaultConfigsMap;

 	/**
 	 * Content provider for the file type TableViewer
 	 */
 	protected class FileTypeContentProvider implements IStructuredContentProvider {

 		private String[] fContent;

 		public FileTypeContentProvider(String[] content) {
 			fContent = content;
 		}

 		/**
 		 * @see IStructuredContentProvider#getElements(Object)
 		 */
 		public Object[] getElements(Object inputElement) {
 			return fContent;
 		}

 		/**
 		 * @see IContentProvider#dispose()
 		 */
 		public void dispose() {
 		}

 		/**
 		 * @see IContentProvider#inputChanged(Viewer, Object, Object)
 		 */
 		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
 		}

 	}

 	/**
 	 * Label provider for the FileType table viewer
 	 */
 	protected class FileTypeLabelProvider extends LabelProvider implements ITableLabelProvider {

 		private Map fExtensionToImageMap;

 		public FileTypeLabelProvider() {
 			initializeExtensionToImageMap();
 		}

 		/**
 		 * Load a table of iamge descriptors keyed by the file extensions they apply to.
 		 */
 		private void initializeExtensionToImageMap() {
 			fExtensionToImageMap = new HashMap(5);
 			IFileEditorMapping[] array = WorkbenchPlugin.getDefault().getEditorRegistry().getFileEditorMappings();
 			for (int i = 0; i < array.length; i++) {
 				IFileEditorMapping mapping = array[i];
 				fExtensionToImageMap.put(mapping.getExtension(), mapping.getImageDescriptor());
 			}
 		}

 		/**
 		 * @see ITableLabelProvider#getColumnText(Object, int)
 		 */
 		public String getColumnText(Object object, int column) {
 			if (column == 0) {
 				return generateElementText(object);
 			}
 			return ""; //$NON-NLS-1$
 		}

 		/**
 		 * @see ILabelProvider#getText(Object)
 		 */
 		public String getText(Object element) {
 			return generateElementText(element);
 		}

 		/**
 		 * @see ITableLabelProvider#getColumnImage(Object, int)
 		 */
 		public Image getColumnImage(Object object, int column) {
 			ImageDescriptor imageDescriptor = (ImageDescriptor) fExtensionToImageMap.get((String)object);
 			return imageDescriptor.createImage(true);
 		}

 		/**
 		 * Convenience method that generates the displayable form of a file type
 		 */
 		private String generateElementText(Object obj) {
 			StringBuffer buffer = new StringBuffer((String)obj);
 			buffer.insert(0, "*.");			//$NON-NLS-1$
 			return buffer.toString();
 		}
 	}

 	/**
 	 * Content provider for the configuration type TableViewer
 	 */
 	protected class ConfigTypeContentProvider implements IStructuredContentProvider {

 		private String fFileTypeInput;

 		/**
 		 * @see IStructuredContentProvider#getElements(Object)
 		 */
 		public Object[] getElements(Object inputElement) {
 			return getLaunchManager().getAllLaunchConfigurationTypesFor(fFileTypeInput);
 		}

 		/**
 		 * @see IContentProvider#dispose()
 		 */
 		public void dispose() {
 		}

 		/**
 		 * @see IContentProvider#inputChanged(Viewer, Object, Object)
 		 */
 		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
 			fFileTypeInput = (String) newInput;
 		}

 	}

 	/**
 	 * Label provider for the configuration table viewer
 	 */
 	protected class ConfigTypeLabelProvider extends LabelProvider implements ITableLabelProvider {

 		/**
 		 * @see ITableLabelProvider#getColumnText(Object, int)
 		 */
 		public String getColumnText(Object object, int column) {
 			if (column == 0) {
 				return generateElementText(object);
 			}
 			return ""; //$NON-NLS-1$
 		}

 		/**
 		 * @see ILabelProvider#getText(Object)
 		 */
 		public String getText(Object element) {
 			return generateElementText(element);
 		}

 		/**
 		 * @see ITableLabelProvider#getColumnImage(Object, int)
 		 */
 		public Image getColumnImage(Object object, int column) {
 			String configTypeID = ((ILaunchConfigurationType)object).getIdentifier();
 			return DebugUITools.getImage(configTypeID);
 		}

 		/**
 		 * Convenience method that generates the displayable form of a file type
 		 */
 		private String generateElementText(Object obj) {
 			ILaunchConfigurationType configType = (ILaunchConfigurationType) obj;
 			StringBuffer buffer = new StringBuffer(configType.getName());
 			String selectedFileType = getFileTypeSelection();
 			if (getDefaultConfigsMap().get(selectedFileType).equals(configType)) {
 				buffer.append(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage._(default)_1")); //$NON-NLS-1$
 			}
 			return buffer.toString();
 		}
 	}

 	/**
 	 * Creates the page's UI content.
 	 */
 	protected Control createContents(Composite parent) {

 		Composite topComp = new Composite(parent, SWT.NULL);
 		GridLayout layout = new GridLayout();
 		layout.numColumns = 2;
 		topComp.setLayout(layout);
 		GridData gd;

 		setFileTypeLabel(new Label(topComp, SWT.LEFT));
 		getFileTypeLabel().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.File_types_2")); //$NON-NLS-1$
 		gd = new GridData();
 		gd.horizontalSpan = 2;
 		getFileTypeLabel().setLayoutData(gd);

 		setFileTypeTableViewer(new TableViewer(topComp, SWT.SINGLE | SWT.BORDER | SWT.FULL_SELECTION));
 		String[] fileTypes = getLaunchManager().getAllRegisteredFileExtensions();
 		getFileTypeTableViewer().setContentProvider(new FileTypeContentProvider(fileTypes));
 		getFileTypeTableViewer().setLabelProvider(new FileTypeLabelProvider());
 		getFileTypeTableViewer().addSelectionChangedListener(new ISelectionChangedListener() {
 			public void selectionChanged(SelectionChangedEvent evt) {
 				handleFileTypeSelectionChanged();
 			}
 		});
 		gd = new GridData(GridData.FILL_BOTH);
 		getFileTypeTableViewer().getTable().setLayoutData(gd);
 		getFileTypeTableViewer().setInput(fileTypes);

 		createSpacer(topComp, 1);
 		createSpacer(topComp, 2);

 		setConfigTypeLabel(new Label(topComp, SWT.LEFT));
 		getConfigTypeLabel().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.Configuration_types_3")); //$NON-NLS-1$
 		gd = new GridData();
 		gd.horizontalSpan = 2;
 		getConfigTypeLabel().setLayoutData(gd);

 		setConfigTypeTableViewer(new TableViewer(topComp, SWT.SINGLE | SWT.BORDER));
 		getConfigTypeTableViewer().setContentProvider(new ConfigTypeContentProvider());
 		getConfigTypeTableViewer().setLabelProvider(new ConfigTypeLabelProvider());
 		getConfigTypeTableViewer().addSelectionChangedListener(new ISelectionChangedListener() {
 			public void selectionChanged(SelectionChangedEvent evt) {
 				handleConfigTypeSelectionChanged();
 			}
 		});
 		gd = new GridData(GridData.FILL_BOTH);
 		getConfigTypeTableViewer().getTable().setLayoutData(gd);

 		setDefaultButton(new Button(topComp, SWT.PUSH));
 		getDefaultButton().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.Set_as_default_4")); //$NON-NLS-1$
 		getDefaultButton().addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent evt) {
 				handleDefaultButtonSelected();
 			}
 		});
 		gd = new GridData(GridData.VERTICAL_ALIGN_BEGINNING);
 		getDefaultButton().setLayoutData(gd);

 		//WorkbenchHelp.setHelp(parent, new DialogPageContextComputer(this, IHelpContextIds.FILE_EDITORS_PREFERENCE_PAGE));

 		return topComp;
 	}

 	protected void createSpacer(Composite composite, int columnSpan) {
 		Label label = new Label(composite, SWT.NONE);
 		GridData gd = new GridData();
 		gd.horizontalSpan = columnSpan;
 		label.setLayoutData(gd);
 	}

 	private void setDefaultConfigsMap(Map defaultConfigsMap) {
 		fDefaultConfigsMap = defaultConfigsMap;
 	}

 	private Map getDefaultConfigsMap() {
 		return fDefaultConfigsMap;
 	}

 	/*****************************************************************************
 	 *
 	 * Accessors for the UI widgets
 	 *
 	 *****************************************************************************/

 	private void setDefaultButton(Button defaultButton) {
 		fDefaultButton = defaultButton;
 	}

 	private Button getDefaultButton() {
 		return fDefaultButton;
 	}

 	private void setConfigTypeTableViewer(TableViewer tableViewer) {
 		fConfigTypeTableViewer = tableViewer;
 	}

 	private TableViewer getConfigTypeTableViewer() {
 		return fConfigTypeTableViewer;
 	}

 	private void setConfigTypeLabel(Label configTypeLabel) {
 		fConfigTypeLabel = configTypeLabel;
 	}

 	private Label getConfigTypeLabel() {
 		return fConfigTypeLabel;
 	}

 	private void setFileTypeLabel(Label fileTypeLabel) {
 		fFileTypeLabel = fileTypeLabel;
 	}

 	private Label getFileTypeLabel() {
 		return fFileTypeLabel;
 	}

 	private void setFileTypeTableViewer(TableViewer tableViewer) {
 		fFileTypeTableViewer = tableViewer;
 	}

 	private TableViewer getFileTypeTableViewer() {
 		return fFileTypeTableViewer;
 	}

 	/*****************************************************************************
 	 *
 	 * Event handling methods
 	 *
 	 *****************************************************************************/

 	/**
 	 * Set the input for the config type viewer based on the current selection in the file type viewer.
 	 * If there is no selection in the viewer, then the config type viewer's input is set to null.
 	 */
 	protected void handleFileTypeSelectionChanged() {
 		String newInput = getFileTypeSelection();
 		getConfigTypeTableViewer().setInput(newInput);
 	}

 	/**
 	 * Set the enabled state of the 'default' button based on the current selection in the
 	 * config type table viewer.
 	 */
 	protected void handleConfigTypeSelectionChanged() {
 		ILaunchConfigurationType configType = getConfigTypeSelection();
 		if (configType == null) {
 			getDefaultButton().setEnabled(false);
 		} else {
 			getDefaultButton().setEnabled(true);
 		}
 	}

 	/**
 	 * Set the currently selected config type in the config type viewer to be the default.
 	 */
 	protected void handleDefaultButtonSelected() {
 		String fileType = getFileTypeSelection();
 		ILaunchConfigurationType configType = getConfigTypeSelection();
 		getDefaultConfigsMap().put(fileType, configType);
 		getConfigTypeTableViewer().refresh();
 	}

 	/**
 	 * Convenience method to return the first selected element in the file type viewer
 	 */
 	protected String getFileTypeSelection() {
 		IStructuredSelection selection = (IStructuredSelection) getFileTypeTableViewer().getSelection();
 		return (String) selection.getFirstElement();
 	}

 	/**
 	 * Convenience method to return the first selected element in the config type viewer
 	 */
 	protected ILaunchConfigurationType getConfigTypeSelection() {
 		IStructuredSelection selection = (IStructuredSelection) getConfigTypeTableViewer().getSelection();
 		return (ILaunchConfigurationType) selection.getFirstElement();
 	}

 	/**
 	 * @see IWorkbenchPreferencePage
 	 */
 	public void init(IWorkbench aWorkbench){
 		readDefaultLaunchConfigs();
 		noDefaultAndApplyButton();
 	}

 	/**
 	 * @see IPreferencePage#performOk()
 	 */
 	public boolean performOk() {
 		saveDefaultLaunchConfigs();
 		return true;
 	}

 	/**
 	 * Populate a local copy of the file extension-->default launch configs mapping from the launch manager.
 	 */
 	protected void readDefaultLaunchConfigs() {
 		ILaunchManager launchManager = getLaunchManager();
 		String[] allFileExtensions = launchManager.getAllRegisteredFileExtensions();
 		setDefaultConfigsMap(new HashMap(allFileExtensions.length));
 		for (int i = 0; i < allFileExtensions.length; i++) {
 			String fileExtension = allFileExtensions[i];
 			ILaunchConfigurationType configType = launchManager.getDefaultLaunchConfigurationType(fileExtension);
 			getDefaultConfigsMap().put(fileExtension, configType);
 		}
 	}

 	/**
 	 * Save the current mapping of file extensions to default launch configs into the launch manager.
 	 */
 	protected void saveDefaultLaunchConfigs() {
 		ILaunchManager launchManager = getLaunchManager();
 		Iterator iterator = getDefaultConfigsMap().keySet().iterator();
 		while (iterator.hasNext()) {
 			String fileExtension = (String) iterator.next();
 			ILaunchConfigurationType configType = (ILaunchConfigurationType) getDefaultConfigsMap().get(fileExtension);
 			launchManager.setDefaultLaunchConfigurationType(fileExtension, configType.getIdentifier());
 		}
 	}

 	/**
 	 * Convenience method to retrieve the launch mananger
 	 */
 	private ILaunchManager getLaunchManager() {
 		return DebugPlugin.getDefault().getLaunchManager();
 	}

 }
	package org.eclipse.debug.internal.ui;

	/*
	* (c) Copyright IBM Corp. 2000, 2001.
	* All Rights Reserved.
	*/

	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.Map;

	import org.eclipse.debug.core.DebugPlugin;
	import org.eclipse.debug.core.ILaunchConfigurationType;
	import org.eclipse.debug.core.ILaunchManager;
	import org.eclipse.debug.ui.DebugUITools;
	import org.eclipse.jface.preference.PreferencePage;
	import org.eclipse.jface.resource.ImageDescriptor;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.IStructuredContentProvider;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.viewers.ITableLabelProvider;
	import org.eclipse.jface.viewers.LabelProvider;
	import org.eclipse.jface.viewers.SelectionChangedEvent;
	import org.eclipse.jface.viewers.TableViewer;
	import org.eclipse.jface.viewers.Viewer;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.ui.IFileEditorMapping;
	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.IWorkbenchPreferencePage;
	import org.eclipse.ui.internal.WorkbenchPlugin;

	public class LaunchConfigurationTypesPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {

	// UI widgets
	private Label fFileTypeLabel;
	private TableViewer fFileTypeTableViewer;
	private Label fConfigTypeLabel;
	private TableViewer fConfigTypeTableViewer;
	private Button fDefaultButton;

	// Local mapping of file extensions to default launch configs. It is necessary to keep a local
	// copy of this in this class so that the user can 'Cancel' out of any changes they make in this
	// preference page.
	private Map fDefaultConfigsMap;

	/**
	* Content provider for the file type TableViewer
	*/
	protected class FileTypeContentProvider implements IStructuredContentProvider {

	private String[] fContent;

	public FileTypeContentProvider(String[] content) {
	fContent = content;
	}

	/**
	* @see IStructuredContentProvider#getElements(Object)
	*/
	public Object[] getElements(Object inputElement) {
	return fContent;
	}

	/**
	* @see IContentProvider#dispose()
	*/
	public void dispose() {
	}

	/**
	* @see IContentProvider#inputChanged(Viewer, Object, Object)
	*/
	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
	}

	}

	/**
	* Label provider for the FileType table viewer
	*/
	protected class FileTypeLabelProvider extends LabelProvider implements ITableLabelProvider {

	private Map fExtensionToImageMap;

	public FileTypeLabelProvider() {
	initializeExtensionToImageMap();
	}

	/**
	* Load a table of iamge descriptors keyed by the file extensions they apply to.
	*/
	private void initializeExtensionToImageMap() {
	fExtensionToImageMap = new HashMap(5);
	IFileEditorMapping[] array = WorkbenchPlugin.getDefault().getEditorRegistry().getFileEditorMappings();
	for (int i = 0; i < array.length; i++) {
	IFileEditorMapping mapping = array[i];
	fExtensionToImageMap.put(mapping.getExtension(), mapping.getImageDescriptor());
	}
	}

	/**
	* @see ITableLabelProvider#getColumnText(Object, int)
	*/
	public String getColumnText(Object object, int column) {
	if (column == 0) {
	return generateElementText(object);
	}
	return ""; //$NON-NLS-1$
	}

	/**
	* @see ILabelProvider#getText(Object)
	*/
	public String getText(Object element) {
	return generateElementText(element);
	}

	/**
	* @see ITableLabelProvider#getColumnImage(Object, int)
	*/
	public Image getColumnImage(Object object, int column) {
	ImageDescriptor imageDescriptor = (ImageDescriptor) fExtensionToImageMap.get((String)object);
	return imageDescriptor.createImage(true);
	}

	/**
	* Convenience method that generates the displayable form of a file type
	*/
	private String generateElementText(Object obj) {
	StringBuffer buffer = new StringBuffer((String)obj);
	buffer.insert(0, "*."); //$NON-NLS-1$
	return buffer.toString();
	}
	}

	/**
	* Content provider for the configuration type TableViewer
	*/
	protected class ConfigTypeContentProvider implements IStructuredContentProvider {

	private String fFileTypeInput;

	/**
	* @see IStructuredContentProvider#getElements(Object)
	*/
	public Object[] getElements(Object inputElement) {
	return getLaunchManager().getAllLaunchConfigurationTypesFor(fFileTypeInput);
	}

	/**
	* @see IContentProvider#dispose()
	*/
	public void dispose() {
	}

	/**
	* @see IContentProvider#inputChanged(Viewer, Object, Object)
	*/
	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
	fFileTypeInput = (String) newInput;
	}

	}

	/**
	* Label provider for the configuration table viewer
	*/
	protected class ConfigTypeLabelProvider extends LabelProvider implements ITableLabelProvider {

	/**
	* @see ITableLabelProvider#getColumnText(Object, int)
	*/
	public String getColumnText(Object object, int column) {
	if (column == 0) {
	return generateElementText(object);
	}
	return ""; //$NON-NLS-1$
	}

	/**
	* @see ILabelProvider#getText(Object)
	*/
	public String getText(Object element) {
	return generateElementText(element);
	}

	/**
	* @see ITableLabelProvider#getColumnImage(Object, int)
	*/
	public Image getColumnImage(Object object, int column) {
	String configTypeID = ((ILaunchConfigurationType)object).getIdentifier();
	return DebugUITools.getImage(configTypeID);
	}

	/**
	* Convenience method that generates the displayable form of a file type
	*/
	private String generateElementText(Object obj) {
	ILaunchConfigurationType configType = (ILaunchConfigurationType) obj;
	StringBuffer buffer = new StringBuffer(configType.getName());
	String selectedFileType = getFileTypeSelection();
	if (getDefaultConfigsMap().get(selectedFileType).equals(configType)) {
	buffer.append(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage._(default)_1")); //$NON-NLS-1$
	}
	return buffer.toString();
	}
	}

	/**
	* Creates the page's UI content.
	*/
	protected Control createContents(Composite parent) {

	Composite topComp = new Composite(parent, SWT.NULL);
	GridLayout layout = new GridLayout();
	layout.numColumns = 2;
	topComp.setLayout(layout);
	GridData gd;

	setFileTypeLabel(new Label(topComp, SWT.LEFT));
	getFileTypeLabel().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.File_types_2")); //$NON-NLS-1$
	gd = new GridData();
	gd.horizontalSpan = 2;
	getFileTypeLabel().setLayoutData(gd);

	setFileTypeTableViewer(new TableViewer(topComp, SWT.SINGLE \| SWT.BORDER \| SWT.FULL_SELECTION));
	String[] fileTypes = getLaunchManager().getAllRegisteredFileExtensions();
	getFileTypeTableViewer().setContentProvider(new FileTypeContentProvider(fileTypes));
	getFileTypeTableViewer().setLabelProvider(new FileTypeLabelProvider());
	getFileTypeTableViewer().addSelectionChangedListener(new ISelectionChangedListener() {
	public void selectionChanged(SelectionChangedEvent evt) {
	handleFileTypeSelectionChanged();
	}
	});
	gd = new GridData(GridData.FILL_BOTH);
	getFileTypeTableViewer().getTable().setLayoutData(gd);
	getFileTypeTableViewer().setInput(fileTypes);

	createSpacer(topComp, 1);
	createSpacer(topComp, 2);

	setConfigTypeLabel(new Label(topComp, SWT.LEFT));
	getConfigTypeLabel().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.Configuration_types_3")); //$NON-NLS-1$
	gd = new GridData();
	gd.horizontalSpan = 2;
	getConfigTypeLabel().setLayoutData(gd);

	setConfigTypeTableViewer(new TableViewer(topComp, SWT.SINGLE \| SWT.BORDER));
	getConfigTypeTableViewer().setContentProvider(new ConfigTypeContentProvider());
	getConfigTypeTableViewer().setLabelProvider(new ConfigTypeLabelProvider());
	getConfigTypeTableViewer().addSelectionChangedListener(new ISelectionChangedListener() {
	public void selectionChanged(SelectionChangedEvent evt) {
	handleConfigTypeSelectionChanged();
	}
	});
	gd = new GridData(GridData.FILL_BOTH);
	getConfigTypeTableViewer().getTable().setLayoutData(gd);

	setDefaultButton(new Button(topComp, SWT.PUSH));
	getDefaultButton().setText(DebugUIMessages.getString("LaunchConfigurationTypesPreferencePage.Set_as_default_4")); //$NON-NLS-1$
	getDefaultButton().addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent evt) {
	handleDefaultButtonSelected();
	}
	});
	gd = new GridData(GridData.VERTICAL_ALIGN_BEGINNING);
	getDefaultButton().setLayoutData(gd);

	//WorkbenchHelp.setHelp(parent, new DialogPageContextComputer(this, IHelpContextIds.FILE_EDITORS_PREFERENCE_PAGE));

	return topComp;
	}

	protected void createSpacer(Composite composite, int columnSpan) {
	Label label = new Label(composite, SWT.NONE);
	GridData gd = new GridData();
	gd.horizontalSpan = columnSpan;
	label.setLayoutData(gd);
	}

	private void setDefaultConfigsMap(Map defaultConfigsMap) {
	fDefaultConfigsMap = defaultConfigsMap;
	}

	private Map getDefaultConfigsMap() {
	return fDefaultConfigsMap;
	}

	/*****************************************************************************
	*
	* Accessors for the UI widgets
	*
	*****************************************************************************/

	private void setDefaultButton(Button defaultButton) {
	fDefaultButton = defaultButton;
	}

	private Button getDefaultButton() {
	return fDefaultButton;
	}

	private void setConfigTypeTableViewer(TableViewer tableViewer) {
	fConfigTypeTableViewer = tableViewer;
	}

	private TableViewer getConfigTypeTableViewer() {
	return fConfigTypeTableViewer;
	}

	private void setConfigTypeLabel(Label configTypeLabel) {
	fConfigTypeLabel = configTypeLabel;
	}

	private Label getConfigTypeLabel() {
	return fConfigTypeLabel;
	}

	private void setFileTypeLabel(Label fileTypeLabel) {
	fFileTypeLabel = fileTypeLabel;
	}

	private Label getFileTypeLabel() {
	return fFileTypeLabel;
	}

	private void setFileTypeTableViewer(TableViewer tableViewer) {
	fFileTypeTableViewer = tableViewer;
	}

	private TableViewer getFileTypeTableViewer() {
	return fFileTypeTableViewer;
	}

	/*****************************************************************************
	*
	* Event handling methods
	*
	*****************************************************************************/

	/**
	* Set the input for the config type viewer based on the current selection in the file type viewer.
	* If there is no selection in the viewer, then the config type viewer's input is set to null.
	*/
	protected void handleFileTypeSelectionChanged() {
	String newInput = getFileTypeSelection();
	getConfigTypeTableViewer().setInput(newInput);
	}

	/**
	* Set the enabled state of the 'default' button based on the current selection in the
	* config type table viewer.
	*/
	protected void handleConfigTypeSelectionChanged() {
	ILaunchConfigurationType configType = getConfigTypeSelection();
	if (configType == null) {
	getDefaultButton().setEnabled(false);
	} else {
	getDefaultButton().setEnabled(true);
	}
	}

	/**
	* Set the currently selected config type in the config type viewer to be the default.
	*/
	protected void handleDefaultButtonSelected() {
	String fileType = getFileTypeSelection();
	ILaunchConfigurationType configType = getConfigTypeSelection();
	getDefaultConfigsMap().put(fileType, configType);
	getConfigTypeTableViewer().refresh();
	}

	/**
	* Convenience method to return the first selected element in the file type viewer
	*/
	protected String getFileTypeSelection() {
	IStructuredSelection selection = (IStructuredSelection) getFileTypeTableViewer().getSelection();
	return (String) selection.getFirstElement();
	}

	/**
	* Convenience method to return the first selected element in the config type viewer
	*/
	protected ILaunchConfigurationType getConfigTypeSelection() {
	IStructuredSelection selection = (IStructuredSelection) getConfigTypeTableViewer().getSelection();
	return (ILaunchConfigurationType) selection.getFirstElement();
	}

	/**
	* @see IWorkbenchPreferencePage
	*/
	public void init(IWorkbench aWorkbench){
	readDefaultLaunchConfigs();
	noDefaultAndApplyButton();
	}

	/**
	* @see IPreferencePage#performOk()
	*/
	public boolean performOk() {
	saveDefaultLaunchConfigs();
	return true;
	}

	/**
	* Populate a local copy of the file extension-->default launch configs mapping from the launch manager.
	*/
	protected void readDefaultLaunchConfigs() {
	ILaunchManager launchManager = getLaunchManager();
	String[] allFileExtensions = launchManager.getAllRegisteredFileExtensions();
	setDefaultConfigsMap(new HashMap(allFileExtensions.length));
	for (int i = 0; i < allFileExtensions.length; i++) {
	String fileExtension = allFileExtensions[i];
	ILaunchConfigurationType configType = launchManager.getDefaultLaunchConfigurationType(fileExtension);
	getDefaultConfigsMap().put(fileExtension, configType);
	}
	}

	/**
	* Save the current mapping of file extensions to default launch configs into the launch manager.
	*/
	protected void saveDefaultLaunchConfigs() {
	ILaunchManager launchManager = getLaunchManager();
	Iterator iterator = getDefaultConfigsMap().keySet().iterator();
	while (iterator.hasNext()) {
	String fileExtension = (String) iterator.next();
	ILaunchConfigurationType configType = (ILaunchConfigurationType) getDefaultConfigsMap().get(fileExtension);
	launchManager.setDefaultLaunchConfigurationType(fileExtension, configType.getIdentifier());
	}
	}

	/**
	* Convenience method to retrieve the launch mananger
	*/
	private ILaunchManager getLaunchManager() {
	return DebugPlugin.getDefault().getLaunchManager();
	}

	}