Dave Jarvis' Repositories

* [JDK 17](https://bell-sw.com/pages/downloads/?version=java-17) (Full JDK + JavaFX)

* [Gradle 7.2](https://gradle.org/releases)

* [Git 2.33](https://git-scm.com/downloads)

After the application is compiled, run it using `keenwrite.sh`.

### Run

Run the application within the IDE as follows:

1. Open **Launcher.java**.

1. Click **Run → Launcher**.

The application is started.

On other platforms, start the application as follows:

1. Download the *full version* of the Java Runtime Environment, [JRE 17](https://bell-sw.com/pages/downloads/?version=java-17).

1. Install the JRE.

1. Open a terminal window.

1. Verify the installation: `java -version`

1. Make `keenwrite.sh` executable.

1. Run: `./keenwrite.sh`

The application is started.

    "--add-exports=javafx.graphics/com.sun.javafx.scene=ALL-UNNAMED",

    "--add-exports=javafx.graphics/com.sun.javafx.scene.text=ALL-UNNAMED",

    "--add-exports=javafx.graphics/com.sun.javafx.scene.traversal=ALL-UNNAMED",

  version = "17"

  def v_junit = '5.8.1'

  def v_jackson = '2.13.0'

  // TODO: Reinstate when JDK 17-compatible release is published

  //implementation 'org.controlsfx:controlsfx:11.1.0'

  implementation 'org.fxmisc.richtext:richtextfx:0.10.7'

  implementation 'org.fxmisc.flowless:flowless:0.6.7'

  implementation 'org.jsoup:jsoup:1.14.3'

  // TODO: Wait for https://github.com/flyingsaucerproject/flyingsaucer/pull/170

  //implementation 'org.xhtmlrenderer:flying-saucer-core:9.1.22'

  //noinspection GradlePackageUpdate

  testImplementation "org.testfx:testfx-junit5:4.0.16-alpha"

readonly OPT_JAVA=$(cat << END_OF_ARGS

--add-opens=javafx.controls/javafx.scene.control=ALL-UNNAMED \

--add-opens=javafx.controls/javafx.scene.control.skin=ALL-UNNAMED \

--add-opens=javafx.graphics/javafx.scene.text=ALL-UNNAMED \

--add-opens=javafx.graphics/com.sun.javafx.css=ALL-UNNAMED \

--add-opens=javafx.graphics/com.sun.javafx.text=ALL-UNNAMED \

--add-exports=javafx.base/com.sun.javafx.event=ALL-UNNAMED \

--add-exports=javafx.graphics/com.sun.javafx.application=ALL-UNNAMED \

--add-exports=javafx.graphics/com.sun.javafx.geom=ALL-UNNAMED \

--add-exports=javafx.graphics/com.sun.javafx.text=ALL-UNNAMED \

--add-exports=javafx.graphics/com.sun.javafx.scene=ALL-UNNAMED \

--add-exports=javafx.graphics/com.sun.javafx.scene.traversal=ALL-UNNAMED

END_OF_ARGS

)

ARG_JAVA_VERSION="17"

ARG_JAVA_UPDATE="35"

java \

  --add-opens=javafx.controls/javafx.scene.control=ALL-UNNAMED \

  --add-opens=javafx.controls/javafx.scene.control.skin=ALL-UNNAMED \

  --add-opens=javafx.graphics/javafx.scene.text=ALL-UNNAMED \

  --add-opens=javafx.graphics/com.sun.javafx.css=ALL-UNNAMED \

  --add-opens=javafx.graphics/com.sun.javafx.text=ALL-UNNAMED \

  --add-exports=javafx.base/com.sun.javafx.event=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.application=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.geom=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.text=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.scene=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.scene.text=ALL-UNNAMED \

  --add-exports=javafx.graphics/com.sun.javafx.scene.traversal=ALL-UNNAMED \

  -jar build/libs/keenwrite.jar

import com.keenwrite.util.ArrayScanner;

    if( !ArrayScanner.contains( args, "--debug" ) ) {

      disableLogging();

    }

import com.keenwrite.preview.HtmlPreview;

import com.keenwrite.processors.Processor;

import com.keenwrite.processors.ProcessorContext;

import com.keenwrite.processors.ProcessorFactory;

import com.keenwrite.processors.markdown.extensions.CaretExtension;

import com.keenwrite.service.events.Notifier;

import com.keenwrite.sigils.RSigilOperator;

import com.keenwrite.sigils.SigilOperator;

import com.keenwrite.sigils.Tokens;

import com.keenwrite.sigils.YamlSigilOperator;

import com.keenwrite.ui.explorer.FilePickerFactory;

import com.keenwrite.ui.heuristics.DocumentStatistics;

import com.keenwrite.ui.outline.DocumentOutline;

import com.panemu.tiwulfx.control.dock.DetachableTab;

import com.panemu.tiwulfx.control.dock.DetachableTabPane;

import javafx.application.Platform;

import javafx.beans.property.*;

import javafx.collections.ListChangeListener;

import javafx.concurrent.Task;

import javafx.event.ActionEvent;

import javafx.event.Event;

import javafx.event.EventHandler;

import javafx.scene.Node;

import javafx.scene.Scene;

import javafx.scene.control.*;

import javafx.scene.control.TreeItem.TreeModificationEvent;

import javafx.scene.input.KeyEvent;

import javafx.scene.layout.FlowPane;

import javafx.stage.Stage;

import javafx.stage.Window;

import org.greenrobot.eventbus.Subscribe;

import java.io.File;

import java.io.FileNotFoundException;

import java.nio.file.Path;

import java.util.*;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.ScheduledExecutorService;

import java.util.concurrent.ScheduledFuture;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicReference;

import java.util.function.Function;

import java.util.stream.Collectors;

import static com.keenwrite.ExportFormat.NONE;

import static com.keenwrite.Messages.get;

import static com.keenwrite.constants.Constants.*;

import static com.keenwrite.constants.GraphicsConstants.ICON_DIALOG_NODE;

import static com.keenwrite.events.Bus.register;

import static com.keenwrite.events.HyperlinkOpenEvent.fireHyperlinkOpenEvent;

import static com.keenwrite.events.StatusEvent.clue;

import static com.keenwrite.io.MediaType.*;

import static com.keenwrite.preferences.WorkspaceKeys.*;

import static com.keenwrite.processors.IdentityProcessor.IDENTITY;

import static com.keenwrite.processors.ProcessorFactory.createProcessors;

import static java.lang.String.format;

import static java.lang.System.getProperty;

import static java.util.concurrent.Executors.newFixedThreadPool;

import static java.util.concurrent.Executors.newScheduledThreadPool;

import static java.util.concurrent.TimeUnit.SECONDS;

import static java.util.stream.Collectors.groupingBy;

import static javafx.application.Platform.runLater;

import static javafx.scene.control.Alert.AlertType.ERROR;

import static javafx.scene.control.ButtonType.*;

import static javafx.scene.control.TabPane.TabClosingPolicy.ALL_TABS;

import static javafx.scene.input.KeyCode.SPACE;

import static javafx.scene.input.KeyCombination.CONTROL_DOWN;

import static javafx.util.Duration.millis;

import static javax.swing.SwingUtilities.invokeLater;

import static org.fxmisc.wellbehaved.event.EventPattern.keyPressed;

/**

 * Responsible for wiring together the main application components for a

 * particular workspace (project). These include the definition views,

 * text editors, and preview pane along with any corresponding controllers.

 */

public final class MainPane extends SplitPane {

  private static final ExecutorService sExecutor = newFixedThreadPool( 1 );

  private final ScheduledExecutorService mSaver = newScheduledThreadPool( 1 );

  private final AtomicReference<ScheduledFuture<?>> mSaveTask =

    new AtomicReference<>();

  private static final Notifier sNotifier = Services.load( Notifier.class );

  /**

   * Used when opening files to determine how each file should be binned and

   * therefore what tab pane to be opened within.

   */

  private static final Set<MediaType> PLAIN_TEXT_FORMAT = Set.of(

    TEXT_MARKDOWN, TEXT_R_MARKDOWN, UNDEFINED

  );

  /**

   * Prevents re-instantiation of processing classes.

   */

  private final Map<TextResource, Processor<String>> mProcessors =

    new HashMap<>();

  private final Workspace mWorkspace;

  /**

   * Groups similar file type tabs together.

   */

  private final List<TabPane> mTabPanes = new ArrayList<>();

  /**

   * Stores definition names and values.

   */

  private final Map<String, String> mResolvedMap =

    new HashMap<>( MAP_SIZE_DEFAULT );

  /**

   * Renders the actively selected plain text editor tab.

   */

  private final HtmlPreview mPreview;

  /**

   * Provides an interactive document outline.

   */

  private final DocumentOutline mOutline = new DocumentOutline();

  /**

   * Changing the active editor fires the value changed event. This allows

   * refreshes to happen when external definitions are modified and need to

   * trigger the processing chain.

   */

  private final ObjectProperty<TextEditor> mActiveTextEditor =

    createActiveTextEditor();

  /**

   * Changing the active definition editor fires the value changed event. This

   * allows refreshes to happen when external definitions are modified and need

   * to trigger the processing chain.

   */

  private final ObjectProperty<TextDefinition> mActiveDefinitionEditor =

    createActiveDefinitionEditor( mActiveTextEditor );

  /**

   * Tracks the number of detached tab panels opened into their own windows,

   * which allows unique identification of subordinate windows by their title.

   * It is doubtful more than 128 windows, much less 256, will be created.

   */

  private byte mWindowCount;

  /**

   * Called when the definition data is changed.

   */

  private final EventHandler<TreeModificationEvent<Event>> mTreeHandler =

    event -> {

      final var editor = mActiveDefinitionEditor.get();

      resolve( editor );

      process( getActiveTextEditor() );

      save( editor );

    };

  private final DocumentStatistics mStatistics;

  /**

   * Adds all content panels to the main user interface. This will load the

   * configuration settings from the workspace to reproduce the settings from

   * a previous session.

   */

  public MainPane( final Workspace workspace ) {

    mWorkspace = workspace;

    mPreview = new HtmlPreview( workspace );

    mStatistics = new DocumentStatistics( workspace );

    mActiveTextEditor.set( new MarkdownEditor( workspace ) );

    open( bin( getRecentFiles() ) );

    viewPreview();

    setDividerPositions( calculateDividerPositions() );

    // Once the main scene's window regains focus, update the active definition

    // editor to the currently selected tab.

    runLater( () -> getWindow().setOnCloseRequest( ( event ) -> {

      // Order matters here. We want to close all the tabs to ensure each

      // is saved, but after they are closed, the workspace should still

      // retain the list of files that were open. If this line came after

      // closing, then restarting the application would list no files.

      mWorkspace.save();

      if( closeAll() ) {

        Platform.exit();

        System.exit( 0 );

      }

      else {

        event.consume();

      }

    } ) );

    register( this );

    initAutosave( workspace );

  }

  @Subscribe

  public void handle( final TextEditorFocusEvent event ) {

    mActiveTextEditor.set( event.get() );

  }

  @Subscribe

  public void handle( final TextDefinitionFocusEvent event ) {

    mActiveDefinitionEditor.set( event.get() );

  }

  /**

   * Typically called when a file name is clicked in the preview panel.

   *

   * @param event The event to process, must contain a valid file reference.

   */

  @Subscribe

  public void handle( final FileOpenEvent event ) {

    final File eventFile;

    final var eventUri = event.getUri();

    if( eventUri.isAbsolute() ) {

      eventFile = new File( eventUri.getPath() );

    }

    else {

      final var activeFile = getActiveTextEditor().getFile();

      final var parent = activeFile.getParentFile();

      if( parent == null ) {

        clue( new FileNotFoundException( eventUri.getPath() ) );

        return;

      }

      else {

        final var parentPath = parent.getAbsolutePath();

        eventFile = Path.of( parentPath, eventUri.getPath() ).toFile();

      }

    }

    runLater( () -> open( eventFile ) );

  }

  @Subscribe

  public void handle( final CaretNavigationEvent event ) {

    runLater( () -> {

      final var textArea = getActiveTextEditor().getTextArea();

      textArea.moveTo( event.getOffset() );

      textArea.requestFollowCaret();

      textArea.requestFocus();

    } );

  }

  @Subscribe

  @SuppressWarnings( "unused" )

  public void handle( final ExportFailedEvent event ) {

    final var os = getProperty( "os.name" );

    final var arch = getProperty( "os.arch" ).toLowerCase();

    final var bits = getProperty( "sun.arch.data.model" );

    final var title = Messages.get( "Alert.typesetter.missing.title" );

    final var header = Messages.get( "Alert.typesetter.missing.header" );

    final var version = Messages.get(

      "Alert.typesetter.missing.version",

      os,

      arch

        .replaceAll( "amd.*|i.*|x86.*", "X86" )

        .replaceAll( "mips.*", "MIPS" )

        .replaceAll( "armv.*", "ARM" ),

      bits );

    final var text = Messages.get( "Alert.typesetter.missing.installer.text" );

    // Download and install ConTeXt for {0} {1} {2}-bit

    final var content = format( "%s %s", text, version );

    final var flowPane = new FlowPane();

    final var link = new Hyperlink( text );

    final var label = new Label( version );

    flowPane.getChildren().addAll( link, label );

    final var alert = new Alert( ERROR, content, OK );

    alert.setTitle( title );

    alert.setHeaderText( header );

    alert.getDialogPane().contentProperty().set( flowPane );

    alert.setGraphic( ICON_DIALOG_NODE );

    link.setOnAction( ( e ) -> {

      alert.close();

      final var url = Messages.get( "Alert.typesetter.missing.installer.url" );

      runLater( () -> fireHyperlinkOpenEvent( url ) );

    } );

    alert.showAndWait();

  }

  private void initAutosave( final Workspace workspace ) {

    final var rate = workspace.integerProperty( KEY_EDITOR_AUTOSAVE );

    rate.addListener(

      ( c, o, n ) -> {

        final var taskRef = mSaveTask.get();

        // Prevent multiple autosaves from running.

        if( taskRef != null ) {

          taskRef.cancel( false );

        }

        initAutosave( rate );

      }

    );

    // Start the save listener (avoids duplicating some code).

    initAutosave( rate );

  }

  private void initAutosave( final IntegerProperty rate ) {

    mSaveTask.set(

      mSaver.scheduleAtFixedRate(

        () -> {

          if( getActiveTextEditor().isModified() ) {

            // Ensure the modified indicator is cleared by running on EDT.

            runLater( this::save );

          }

        }, 0, rate.intValue(), SECONDS

      )

    );

  }

  /**

   * TODO: Load divider positions from exported settings, see

   *   {@link #bin(SetProperty)} comment.

   */

  private double[] calculateDividerPositions() {

    final var ratio = 100f / getItems().size() / 100;

    final var positions = getDividerPositions();

    for( int i = 0; i < positions.length; i++ ) {

      positions[ i ] = ratio * i;

    }

    return positions;

  }

  /**

   * Opens all the files into the application, provided the paths are unique.

   * This may only be called for any type of files that a user can edit

   * (i.e., update and persist), such as definitions and text files.

   *

   * @param files The list of files to open.

   */

  public void open( final List<File> files ) {

    files.forEach( this::open );

  }

  /**

   * This opens the given file. Since the preview pane is not a file that

   * can be opened, it is safe to add a listener to the detachable pane.

   *

   * @param file The file to open.

   */

  private void open( final File file ) {

    final var tab = createTab( file );

    final var node = tab.getContent();

    final var mediaType = MediaType.valueFrom( file );

    final var tabPane = obtainTabPane( mediaType );

    tab.setTooltip( createTooltip( file ) );

    tabPane.setFocusTraversable( false );

    tabPane.setTabClosingPolicy( ALL_TABS );

    tabPane.getTabs().add( tab );

    // Attach the tab scene factory for new tab panes.

    if( !getItems().contains( tabPane ) ) {

      addTabPane(

        node instanceof TextDefinition ? 0 : getItems().size(), tabPane

      );

    }

    getRecentFiles().add( file.getAbsolutePath() );

  }

  /**

   * Opens a new text editor document using the default document file name.

   */

  public void newTextEditor() {

    open( DOCUMENT_DEFAULT );

  }

  /**

   * Opens a new definition editor document using the default definition

   * file name.

   */

  public void newDefinitionEditor() {

    open( DEFINITION_DEFAULT );

  }

  /**

   * Iterates over all tab panes to find all {@link TextEditor}s and request

   * that they save themselves.

   */

  public void saveAll() {

    mTabPanes.forEach(

      ( tp ) -> tp.getTabs().forEach( ( tab ) -> {

        final var node = tab.getContent();

        if( node instanceof final TextEditor editor ) {

          save( editor );

        }

      } )

    );

  }

  /**

   * Requests that the active {@link TextEditor} saves itself. Don't bother

   * checking if modified first because if the user swaps external media from

   * an external source (e.g., USB thumb drive), save should not second-guess

   * the user: save always re-saves. Also, it's less code.

   */

  public void save() {

    save( getActiveTextEditor() );

  }

  /**

   * Saves the active {@link TextEditor} under a new name.

   *

   * @param files The new active editor {@link File} reference, must contain

   *              at least one element.

   */

  public void saveAs( final List<File> files ) {

    assert files != null;

    assert !files.isEmpty();

    final var editor = getActiveTextEditor();

    final var tab = getTab( editor );

    final var file = files.get( 0 );

    editor.rename( file );

    tab.ifPresent( t -> {

      t.setText( editor.getFilename() );

      t.setTooltip( createTooltip( file ) );

    } );

    save();

  }

  /**

   * Saves the given {@link TextResource} to a file. This is typically used

   * to save either an instance of {@link TextEditor} or {@link TextDefinition}.

   *

   * @param resource The resource to export.

   */

  private void save( final TextResource resource ) {

    try {

      resource.save();

    } catch( final Exception ex ) {

      clue( ex );

      sNotifier.alert(

        getWindow(), resource.getPath(), "TextResource.saveFailed", ex

      );

    }

  }

  /**

   * Closes all open {@link TextEditor}s; all {@link TextDefinition}s stay open.

   *

   * @return {@code true} when all editors, modified or otherwise, were

   * permitted to close; {@code false} when one or more editors were modified

   * and the user requested no closing.

   */

  public boolean closeAll() {

    var closable = true;

    for( final var tabPane : mTabPanes ) {

      final var tabIterator = tabPane.getTabs().iterator();

      while( tabIterator.hasNext() ) {

        final var tab = tabIterator.next();

        final var resource = tab.getContent();

        // The definition panes auto-save, so being specific here prevents

        // closing the definitions in the situation where the user wants to

        // continue editing (i.e., possibly save unsaved work).

        if( !(resource instanceof TextEditor) ) {

          continue;

        }

        if( canClose( (TextEditor) resource ) ) {

          tabIterator.remove();

          close( tab );

        }

        else {

          closable = false;

        }

      }

    }

    return closable;

  }

  /**

   * Calls the tab's {@link Tab#getOnClosed()} handler to carry out a close

   * event.

   *

   * @param tab The {@link Tab} that was closed.

   */

  private void close( final Tab tab ) {

    assert tab != null;

    final var handler = tab.getOnClosed();

    if( handler != null ) {

      handler.handle( new ActionEvent() );

    }

  }

  /**

   * Closes the active tab; delegates to {@link #canClose(TextResource)}.

   */

  public void close() {

    final var editor = getActiveTextEditor();

    if( canClose( editor ) ) {

      close( editor );

    }

  }

  /**

   * Closes the given {@link TextResource}. This must not be called from within

   * a loop that iterates over the tab panes using {@code forEach}, lest a

   * concurrent modification exception be thrown.

   *

   * @param resource The {@link TextResource} to close, without confirming with

   *                 the user.

   */

  private void close( final TextResource resource ) {

    getTab( resource ).ifPresent(

      ( tab ) -> {

        close( tab );

        tab.getTabPane().getTabs().remove( tab );

      }

    );

  }

  /**

   * Answers whether the given {@link TextResource} may be closed.

   *

   * @param editor The {@link TextResource} to try closing.

   * @return {@code true} when the editor may be closed; {@code false} when

   * the user has requested to keep the editor open.

   */

  private boolean canClose( final TextResource editor ) {

    final var editorTab = getTab( editor );

    final var canClose = new AtomicBoolean( true );

    if( editor.isModified() ) {

      final var filename = new StringBuilder();

      editorTab.ifPresent( ( tab ) -> filename.append( tab.getText() ) );

      final var message = sNotifier.createNotification(

        Messages.get( "Alert.file.close.title" ),

        Messages.get( "Alert.file.close.text" ),

        filename.toString()

      );

      final var dialog = sNotifier.createConfirmation( getWindow(), message );

      dialog.showAndWait().ifPresent(

        save -> canClose.set( save == YES ? editor.save() : save == NO )

      );

    }

    return canClose.get();

  }

  private ObjectProperty<TextEditor> createActiveTextEditor() {

    final var editor = new SimpleObjectProperty<TextEditor>();

    editor.addListener( ( c, o, n ) -> {

      if( n != null ) {

        mPreview.setBaseUri( n.getPath() );

        process( n );

      }

    } );

    return editor;

  }

  /**

   * Adds the HTML preview tab to its own, singular tab pane.

   */

  public void viewPreview() {

    viewTab( mPreview, TEXT_HTML, "Pane.preview.title" );

  }

  /**

   * Adds the document outline tab to its own, singular tab pane.

   */

  public void viewOutline() {

    viewTab( mOutline, APP_DOCUMENT_OUTLINE, "Pane.outline.title" );

  }

  public void viewStatistics() {

    viewTab( mStatistics, APP_DOCUMENT_STATISTICS, "Pane.statistics.title" );

  }

  public void viewFiles() {

    try {

      final var factory = new FilePickerFactory( mWorkspace );

      final var fileManager = factory.createModeless();

      viewTab( fileManager, APP_FILE_MANAGER, "Pane.files.title" );

    } catch( final Exception ex ) {

      clue( ex );

    }

  }

  private void viewTab(

    final Node node, final MediaType mediaType, final String key ) {

    final var tabPane = obtainTabPane( mediaType );

    for( final var tab : tabPane.getTabs() ) {

      if( tab.getContent() == node ) {

        return;

      }

    }

    tabPane.getTabs().add( createTab( get( key ), node ) );

    addTabPane( tabPane );

  }

  public void viewRefresh() {

    mPreview.refresh();

  }

  /**

   * Returns the tab that contains the given {@link TextEditor}.

   *

   * @param editor The {@link TextEditor} instance to find amongst the tabs.

   * @return The first tab having content that matches the given tab.

   */

  private Optional<Tab> getTab( final TextResource editor ) {

    return mTabPanes.stream()

                    .flatMap( pane -> pane.getTabs().stream() )

                    .filter( tab -> editor.equals( tab.getContent() ) )

                    .findFirst();

  }

  /**

   * Creates a new {@link DefinitionEditor} wrapped in a listener that

   * is used to detect when the active {@link DefinitionEditor} has changed.

   * Upon changing, the {@link #mResolvedMap} is updated and the active

   * text editor is refreshed.

   *

   * @param editor Text editor to update with the revised resolved map.

   * @return A newly configured property that represents the active

   * {@link DefinitionEditor}, never null.

   */

  private ObjectProperty<TextDefinition> createActiveDefinitionEditor(

    final ObjectProperty<TextEditor> editor ) {

    final var definitions = new SimpleObjectProperty<TextDefinition>();

    definitions.addListener( ( c, o, n ) -> {

      resolve( n == null ? createDefinitionEditor() : n );

      process( editor.get() );

    } );

    return definitions;

  }

  private Tab createTab( final String filename, final Node node ) {

    return new DetachableTab( filename, node );

  }

  private Tab createTab( final File file ) {

    final var r = createTextResource( file );

    final var tab = createTab( r.getFilename(), r.getNode() );

    r.modifiedProperty().addListener(

      ( c, o, n ) -> tab.setText( r.getFilename() + (n ? "*" : "") )

    );

    // This is called when either the tab is closed by the user clicking on

    // the tab's close icon or when closing (all) from the file menu.

    tab.setOnClosed(

      ( __ ) -> getRecentFiles().remove( file.getAbsolutePath() )

    );

    // When closing a tab, give focus to the newly revealed tab.

    tab.selectedProperty().addListener( ( c, o, n ) -> {

      if( n != null && n ) {

        final var pane = tab.getTabPane();

        if( pane != null ) {

          pane.requestFocus();

        }

      }

    } );

 * allows dynamic edits of the {@link TreeView} to be displayed without

 * having to reload the definition file. Reloading the definition file would

 * work, but has a number of drawbacks.