Dave Jarvis' Repositories

Author	djarvis <email>
Date	2017-01-04 22:05:01 GMT-0800
Commit	7bbc62ee1da949e613f2cd176b9eedfecaa12c35
Parent	3a9d0bf
Delta	609 lines added, 557 lines removed, 52-line increase

src/main/java/com/scrivenvar/MainWindow.java

		import com.scrivenvar.editors.VariableNameInjector;
		import com.scrivenvar.editors.markdown.MarkdownEditorPane;
		-import com.scrivenvar.preview.HTMLPreviewPane;
		-import com.scrivenvar.processors.Processor;
		-import com.scrivenvar.processors.ProcessorFactory;
		-import com.scrivenvar.service.Options;
		-import com.scrivenvar.service.Snitch;
		-import com.scrivenvar.service.events.Notifier;
		-import com.scrivenvar.util.Action;
		-import com.scrivenvar.util.ActionUtils;
		-import static com.scrivenvar.util.StageState.*;
		-import static de.jensd.fx.glyphs.fontawesome.FontAwesomeIcon.*;
		-import java.nio.file.Path;
		-import java.util.HashMap;
		-import java.util.Map;
		-import java.util.Observable;
		-import java.util.Observer;
		-import java.util.function.Function;
		-import java.util.prefs.Preferences;
		-import javafx.application.Platform;
		-import javafx.beans.binding.Bindings;
		-import javafx.beans.binding.BooleanBinding;
		-import javafx.beans.property.BooleanProperty;
		-import javafx.beans.property.SimpleBooleanProperty;
		-import javafx.beans.value.ObservableBooleanValue;
		-import javafx.beans.value.ObservableValue;
		-import javafx.collections.ListChangeListener.Change;
		-import javafx.collections.ObservableList;
		-import static javafx.event.Event.fireEvent;
		-import javafx.geometry.Pos;
		-import javafx.scene.Node;
		-import javafx.scene.Scene;
		-import javafx.scene.control.Alert;
		-import javafx.scene.control.Alert.AlertType;
		-import javafx.scene.control.Menu;
		-import javafx.scene.control.MenuBar;
		-import javafx.scene.control.SplitPane;
		-import javafx.scene.control.Tab;
		-import javafx.scene.control.ToolBar;
		-import javafx.scene.control.TreeView;
		-import javafx.scene.image.Image;
		-import javafx.scene.image.ImageView;
		-import static javafx.scene.input.KeyCode.ESCAPE;
		-import javafx.scene.input.KeyEvent;
		-import static javafx.scene.input.KeyEvent.CHAR_UNDEFINED;
		-import static javafx.scene.input.KeyEvent.KEY_PRESSED;
		-import javafx.scene.layout.BorderPane;
		-import javafx.scene.layout.VBox;
		-import javafx.scene.text.Text;
		-import javafx.stage.Window;
		-import javafx.stage.WindowEvent;
		-import static javafx.stage.WindowEvent.WINDOW_CLOSE_REQUEST;
		-import org.controlsfx.control.StatusBar;
		-import org.fxmisc.richtext.model.TwoDimensional.Position;
		-
		-/**
		- * Main window containing a tab pane in the center for file editors.
		- *
		- * @author Karl Tauber and White Magic Software, Ltd.
		- */
		-public class MainWindow implements Observer {
		-
		- private final Options options = Services.load( Options.class );
		- private final Snitch snitch = Services.load( Snitch.class );
		- private final Notifier notifier = Services.load( Notifier.class );
		-
		- private Scene scene;
		- private MenuBar menuBar;
		- private StatusBar statusBar;
		- private Text lineNumberText;
		-
		- private DefinitionSource definitionSource;
		- private DefinitionPane definitionPane;
		- private FileEditorTabPane fileEditorPane;
		- private HTMLPreviewPane previewPane;
		-
		- /**
		- * Prevent re-instantiation processing classes.
		- */
		- private Map<FileEditorTab, Processor<String>> processors;
		-
		- public MainWindow() {
		- initLayout();
		- initDefinitionListener();
		- initTabAddedListener();
		- initTabChangedListener();
		- initPreferences();
		- initSnitch();
		- }
		-
		- /**
		- * Listen for file editor tab pane to receive an open definition source event.
		- */
		- private void initDefinitionListener() {
		- getFileEditorPane().onOpenDefinitionFileProperty().addListener(
		- (ObservableValue<? extends Path> definitionFile,
		- final Path oldPath, final Path newPath) -> {
		- openDefinition( newPath );
		-
		- // Indirectly refresh the resolved map.
		- setProcessors( null );
		-
		- updateDefinitionPane();
		-
		- // Will create new processors and therefore a new resolved map.
		- refreshSelectedTab( getActiveFileEditor() );
		- }
		- );
		- }
		-
		- /**
		- * When tabs are added, hook the various change listeners onto the new tab so
		- * that the preview pane refreshes as necessary.
		- */
		- private void initTabAddedListener() {
		- final FileEditorTabPane editorPane = getFileEditorPane();
		-
		- // Make sure the text processor kicks off when new files are opened.
		- final ObservableList<Tab> tabs = editorPane.getTabs();
		-
		- // Update the preview pane on tab changes.
		- tabs.addListener(
		- (final Change<? extends Tab> change) -> {
		- while( change.next() ) {
		- if( change.wasAdded() ) {
		- // Multiple tabs can be added simultaneously.
		- for( final Tab newTab : change.getAddedSubList() ) {
		- final FileEditorTab tab = (FileEditorTab)newTab;
		-
		- initTextChangeListener( tab );
		- initCaretParagraphListener( tab );
		- initVariableNameInjector( tab );
		-// initSyntaxListener( tab );
		- }
		- }
		- }
		- }
		- );
		- }
		-
		- /**
		- * Reloads the preferences from the previous load.
		- */
		- private void initPreferences() {
		- restoreDefinitionSource();
		- getFileEditorPane().restorePreferences();
		- updateDefinitionPane();
		- }
		-
		- /**
		- * Listen for new tab selection events.
		- */
		- private void initTabChangedListener() {
		- final FileEditorTabPane editorPane = getFileEditorPane();
		-
		- // Update the preview pane changing tabs.
		- editorPane.addTabSelectionListener(
		- (ObservableValue<? extends Tab> tabPane,
		- final Tab oldTab, final Tab newTab) -> {
		-
		- // If there was no old tab, then this is a first time load, which
		- // can be ignored.
		- if( oldTab != null ) {
		- if( newTab == null ) {
		- closeRemainingTab();
		- }
		- else {
		- // Update the preview with the edited text.
		- refreshSelectedTab( (FileEditorTab)newTab );
		- }
		- }
		- }
		- );
		- }
		-
		- private void initTextChangeListener( final FileEditorTab tab ) {
		- tab.addTextChangeListener(
		- (ObservableValue<? extends String> editor,
		- final String oldValue, final String newValue) -> {
		- refreshSelectedTab( tab );
		- }
		- );
		- }
		-
		- private void initCaretParagraphListener( final FileEditorTab tab ) {
		- tab.addCaretParagraphListener(
		- (ObservableValue<? extends Integer> editor,
		- final Integer oldValue, final Integer newValue) -> {
		- refreshSelectedTab( tab );
		- }
		- );
		- }
		-
		- private void initVariableNameInjector( final FileEditorTab tab ) {
		- VariableNameInjector.listen( tab, getDefinitionPane() );
		- }
		-
		- /**
		- * Watch for changes to external files. In particular, this awaits
		- * modifications to any XSL files associated with XML files being edited. When
		- * an XSL file is modified (external to the application), the snitch's ears
		- * perk up and the file is reloaded. This keeps the XSL transformation up to
		- * date with what's on the file system.
		- */
		- private void initSnitch() {
		- getSnitch().addObserver( this );
		- }
		-
		- /**
		- * Called whenever the preview pane becomes out of sync with the file editor
		- * tab. This can be called when the text changes, the caret paragraph changes,
		- * or the file tab changes.
		- *
		- * @param tab The file editor tab that has been changed in some fashion.
		- */
		- private void refreshSelectedTab( final FileEditorTab tab ) {
		- if( tab.isFileOpen() ) {
		- getPreviewPane().setPath( tab.getPath() );
		-
		- // TODO: https://github.com/DaveJarvis/scrivenvar/issues/29
		- final Position p = tab.getCaretOffset();
		- getLineNumberText().setText(
		- get( STATUS_BAR_LINE,
		- p.getMajor() + 1,
		- p.getMinor() + 1,
		- tab.getCaretPosition() + 1
		- )
		- );
		-
		- Processor<String> processor = getProcessors().get( tab );
		-
		- if( processor == null ) {
		- processor = createProcessor( tab );
		- getProcessors().put( tab, processor );
		- }
		-
		- try {
		- getNotifier().clear();
		- processor.processChain( tab.getEditorText() );
		- } catch( final Exception ex ) {
		- error( ex );
		- }
		- }
		- }
		-
		- /**
		- * Returns the variable map of interpolated definitions.
		- *
		- * @return A map to help dereference variables.
		- */
		- private Map<String, String> getResolvedMap() {
		- return getDefinitionSource().getResolvedMap();
		- }
		-
		- /**
		- * Returns the root node for the hierarchical definition source.
		- *
		- * @return Data to display in the definition pane.
		- */
		- private TreeView<String> getTreeView() {
		- try {
		- return getDefinitionSource().asTreeView();
		- } catch( Exception e ) {
		- error( e );
		- }
		-
		- // Slightly redundant as getDefinitionSource() might have returned an
		- // empty definition source.
		- return (new EmptyDefinitionSource()).asTreeView();
		- }
		-
		- /**
		- * Called when a definition source is opened.
		- *
		- * @param path Path to the definition source that was opened.
		- */
		- private void openDefinition( final Path path ) {
		- try {
		- final DefinitionSource ds = createDefinitionSource( path.toString() );
		- setDefinitionSource( ds );
		- storeDefinitionSource();
		- updateDefinitionPane();
		- } catch( final Exception e ) {
		- error( e );
		- }
		- }
		-
		- private void updateDefinitionPane() {
		- getDefinitionPane().setRoot( getDefinitionSource().asTreeView() );
		- }
		-
		- private void restoreDefinitionSource() {
		- final Preferences preferences = getPreferences();
		- final String source = preferences.get( PREFS_DEFINITION_SOURCE, null );
		-
		- // If there's no definition source set, don't try to load it.
		- if( source != null ) {
		- setDefinitionSource( createDefinitionSource( source ) );
		- }
		- }
		-
		- private void storeDefinitionSource() {
		- final Preferences preferences = getPreferences();
		- final DefinitionSource ds = getDefinitionSource();
		-
		- preferences.put( PREFS_DEFINITION_SOURCE, ds.toString() );
		- }
		-
		- /**
		- * Called when the last open tab is closed to clear the preview pane.
		- */
		- private void closeRemainingTab() {
		- getPreviewPane().clear();
		- }
		-
		- /**
		- * Called when an exception occurs that warrants the user's attention.
		- *
		- * @param e The exception with a message that the user should know about.
		- */
		- private void error( final Exception e ) {
		- getNotifier().notify( e );
		- }
		-
		- //---- File actions -------------------------------------------------------
		- /**
		- * Called when an observable instance has changed. This includes the snitch
		- * service and the notify service.
		- *
		- * @param observable The observed instance.
		- * @param value The noteworthy item.
		- */
		- @Override
		- public void update( final Observable observable, final Object value ) {
		- if( value != null ) {
		- if( observable instanceof Snitch && value instanceof Path ) {
		- update( (Path)value );
		- }
		- else if( observable instanceof Notifier && value instanceof String ) {
		- final String s = (String)value;
		- final int index = s.indexOf( '\n' );
		- final String message = s.substring( 0, index > 0 ? index : s.length() );
		-
		- getStatusBar().setText( message );
		- }
		- }
		- }
		-
		- /**
		- * Called when a file has been modified.
		- *
		- * @param file Path to the modified file.
		- */
		- private void update( final Path file ) {
		- // Avoid throwing IllegalStateException by running from a non-JavaFX thread.
		- Platform.runLater(
		- () -> {
		- // Brute-force XSLT file reload by re-instantiating all processors.
		- resetProcessors();
		- refreshSelectedTab( getActiveFileEditor() );
		- }
		- );
		- }
		-
		- /**
		- * After resetting the processors, they will refresh anew to be up-to-date
		- * with the files (text and definition) currently loaded into the editor.
		- */
		- private void resetProcessors() {
		- getProcessors().clear();
		- }
		-
		- //---- File actions -------------------------------------------------------
		- private void fileNew() {
		- getFileEditorPane().newEditor();
		- }
		-
		- private void fileOpen() {
		- getFileEditorPane().openFileDialog();
		- }
		-
		- private void fileClose() {
		- getFileEditorPane().closeEditor( getActiveFileEditor(), true );
		- }
		-
		- private void fileCloseAll() {
		- getFileEditorPane().closeAllEditors();
		- }
		-
		- private void fileSave() {
		- getFileEditorPane().saveEditor( getActiveFileEditor() );
		- }
		-
		- private void fileSaveAll() {
		- getFileEditorPane().saveAllEditors();
		- }
		-
		- private void fileExit() {
		- final Window window = getWindow();
		- fireEvent( window, new WindowEvent( window, WINDOW_CLOSE_REQUEST ) );
		- }
		-
		- //---- Help actions -------------------------------------------------------
		- private void helpAbout() {
		- Alert alert = new Alert( AlertType.INFORMATION );
		- alert.setTitle( get( "Dialog.about.title" ) );
		- alert.setHeaderText( get( "Dialog.about.header" ) );
		- alert.setContentText( get( "Dialog.about.content" ) );
		- alert.setGraphic( new ImageView( new Image( FILE_LOGO_32 ) ) );
		- alert.initOwner( getWindow() );
		-
		- alert.showAndWait();
		- }
		-
		- //---- Convenience accessors ----------------------------------------------
		- private float getFloat( final String key, final float defaultValue ) {
		- return getPreferences().getFloat( key, defaultValue );
		- }
		-
		- private Preferences getPreferences() {
		- return getOptions().getState();
		- }
		-
		- protected Scene getScene() {
		- if( this.scene == null ) {
		- this.scene = createScene();
		- }
		-
		- return this.scene;
		- }
		-
		- public Window getWindow() {
		- return getScene().getWindow();
		- }
		-
		- private MarkdownEditorPane getActiveEditor() {
		- final EditorPane pane = getActiveFileEditor().getEditorPane();
		-
		- return pane instanceof MarkdownEditorPane ? (MarkdownEditorPane)pane : null;
		- }
		-
		- private FileEditorTab getActiveFileEditor() {
		- return getFileEditorPane().getActiveFileEditor();
		- }
		-
		- //---- Member accessors ---------------------------------------------------
		- private void setScene( Scene scene ) {
		- this.scene = scene;
		- }
		-
		- private void setProcessors( final Map<FileEditorTab, Processor<String>> map ) {
		- this.processors = map;
		- }
		-
		- private Map<FileEditorTab, Processor<String>> getProcessors() {
		- if( this.processors == null ) {
		- setProcessors( new HashMap<>() );
		- }
		-
		- return this.processors;
		- }
		-
		- private FileEditorTabPane getFileEditorPane() {
		- if( this.fileEditorPane == null ) {
		- this.fileEditorPane = createFileEditorPane();
		- }
		-
		- return this.fileEditorPane;
		- }
		-
		- private HTMLPreviewPane getPreviewPane() {
		- if( this.previewPane == null ) {
		- this.previewPane = createPreviewPane();
		- }
		-
		- return this.previewPane;
		- }
		-
		- private void setDefinitionSource( final DefinitionSource definitionSource ) {
		- this.definitionSource = definitionSource;
		- }
		-
		- private DefinitionSource getDefinitionSource() {
		- if( this.definitionSource == null ) {
		- this.definitionSource = new EmptyDefinitionSource();
		- }
		-
		- return this.definitionSource;
		- }
		-
		- private DefinitionPane getDefinitionPane() {
		- if( this.definitionPane == null ) {
		- this.definitionPane = createDefinitionPane();
		- }
		-
		- return this.definitionPane;
		- }
		-
		- private Options getOptions() {
		- return this.options;
		- }
		-
		- private Snitch getSnitch() {
		- return this.snitch;
		- }
		-
		- private Notifier getNotifier() {
		- return this.notifier;
		- }
		-
		- public void setMenuBar( final MenuBar menuBar ) {
		- this.menuBar = menuBar;
		- }
		-
		- public MenuBar getMenuBar() {
		- return this.menuBar;
		- }
		-
		- private Text getLineNumberText() {
		- if( this.lineNumberText == null ) {
		- this.lineNumberText = createLineNumberText();
		- }
		-
		- return this.lineNumberText;
		- }
		-
		- private synchronized StatusBar getStatusBar() {
		- if( this.statusBar == null ) {
		- this.statusBar = createStatusBar();
		- }
		-
		- return this.statusBar;
		- }
		-
		- //---- Member creators ----------------------------------------------------
		- /**
		- * Factory to create processors that are suited to different file types.
		- *
		- * @param tab The tab that is subjected to processing.
		- *
		- * @return A processor suited to the file type specified by the tab's path.
		- */
		- private Processor<String> createProcessor( final FileEditorTab tab ) {
		- return createProcessorFactory().createProcessor( tab );
		- }
		-
		- private ProcessorFactory createProcessorFactory() {
		- return new ProcessorFactory( getPreviewPane(), getResolvedMap() );
		- }
		-
		- private DefinitionSource createDefinitionSource( final String path ) {
		- return createDefinitionFactory().createDefinitionSource( path );
		+import com.scrivenvar.predicates.files.FileTypePredicate;
		+import com.scrivenvar.preview.HTMLPreviewPane;
		+import com.scrivenvar.processors.Processor;
		+import com.scrivenvar.processors.ProcessorFactory;
		+import com.scrivenvar.service.Options;
		+import com.scrivenvar.service.Snitch;
		+import com.scrivenvar.service.events.Notifier;
		+import com.scrivenvar.util.Action;
		+import com.scrivenvar.util.ActionUtils;
		+import static com.scrivenvar.util.StageState.*;
		+import static de.jensd.fx.glyphs.fontawesome.FontAwesomeIcon.*;
		+import java.io.IOException;
		+import java.nio.file.Path;
		+import java.util.HashMap;
		+import java.util.Map;
		+import java.util.Observable;
		+import java.util.Observer;
		+import java.util.function.Function;
		+import java.util.prefs.Preferences;
		+import javafx.application.Platform;
		+import javafx.beans.binding.Bindings;
		+import javafx.beans.binding.BooleanBinding;
		+import javafx.beans.property.BooleanProperty;
		+import javafx.beans.property.SimpleBooleanProperty;
		+import javafx.beans.value.ObservableBooleanValue;
		+import javafx.beans.value.ObservableValue;
		+import javafx.collections.ListChangeListener.Change;
		+import javafx.collections.ObservableList;
		+import static javafx.event.Event.fireEvent;
		+import javafx.geometry.Pos;
		+import javafx.scene.Node;
		+import javafx.scene.Scene;
		+import javafx.scene.control.Alert;
		+import javafx.scene.control.Alert.AlertType;
		+import javafx.scene.control.Menu;
		+import javafx.scene.control.MenuBar;
		+import javafx.scene.control.SplitPane;
		+import javafx.scene.control.Tab;
		+import javafx.scene.control.ToolBar;
		+import javafx.scene.control.TreeView;
		+import javafx.scene.image.Image;
		+import javafx.scene.image.ImageView;
		+import static javafx.scene.input.KeyCode.ESCAPE;
		+import javafx.scene.input.KeyEvent;
		+import static javafx.scene.input.KeyEvent.CHAR_UNDEFINED;
		+import static javafx.scene.input.KeyEvent.KEY_PRESSED;
		+import javafx.scene.layout.BorderPane;
		+import javafx.scene.layout.VBox;
		+import javafx.scene.text.Text;
		+import javafx.stage.Window;
		+import javafx.stage.WindowEvent;
		+import static javafx.stage.WindowEvent.WINDOW_CLOSE_REQUEST;
		+import org.controlsfx.control.StatusBar;
		+import org.fxmisc.richtext.model.TwoDimensional.Position;
		+
		+/**
		+ * Main window containing a tab pane in the center for file editors.
		+ *
		+ * @author Karl Tauber and White Magic Software, Ltd.
		+ */
		+public class MainWindow implements Observer {
		+
		+ private final Options options = Services.load( Options.class );
		+ private final Snitch snitch = Services.load( Snitch.class );
		+ private final Notifier notifier = Services.load( Notifier.class );
		+
		+ private Scene scene;
		+ private MenuBar menuBar;
		+ private StatusBar statusBar;
		+ private Text lineNumberText;
		+
		+ private DefinitionSource definitionSource;
		+ private DefinitionPane definitionPane;
		+ private FileEditorTabPane fileEditorPane;
		+ private HTMLPreviewPane previewPane;
		+
		+ /**
		+ * Prevent re-instantiation processing classes.
		+ */
		+ private Map<FileEditorTab, Processor<String>> processors;
		+
		+ public MainWindow() {
		+ initLayout();
		+ initSnitch();
		+ initDefinitionListener();
		+ initTabAddedListener();
		+ initTabChangedListener();
		+ initPreferences();
		+ }
		+
		+ /**
		+ * Listen for file editor tab pane to receive an open definition source event.
		+ */
		+ private void initDefinitionListener() {
		+ getFileEditorPane().onOpenDefinitionFileProperty().addListener(
		+ (ObservableValue<? extends Path> definitionFile,
		+ final Path oldPath, final Path newPath) -> {
		+ openDefinition( newPath );
		+
		+ // Indirectly refresh the resolved map.
		+ setProcessors( null );
		+
		+ updateDefinitionPane();
		+
		+ try {
		+ getSnitch().ignore( oldPath );
		+ getSnitch().listen( newPath );
		+ } catch( final IOException ex ) {
		+ error( ex );
		+ }
		+
		+ // Will create new processors and therefore a new resolved map.
		+ refreshSelectedTab( getActiveFileEditor() );
		+ }
		+ );
		+ }
		+
		+ /**
		+ * When tabs are added, hook the various change listeners onto the new tab so
		+ * that the preview pane refreshes as necessary.
		+ */
		+ private void initTabAddedListener() {
		+ final FileEditorTabPane editorPane = getFileEditorPane();
		+
		+ // Make sure the text processor kicks off when new files are opened.
		+ final ObservableList<Tab> tabs = editorPane.getTabs();
		+
		+ // Update the preview pane on tab changes.
		+ tabs.addListener(
		+ (final Change<? extends Tab> change) -> {
		+ while( change.next() ) {
		+ if( change.wasAdded() ) {
		+ // Multiple tabs can be added simultaneously.
		+ for( final Tab newTab : change.getAddedSubList() ) {
		+ final FileEditorTab tab = (FileEditorTab)newTab;
		+
		+ initTextChangeListener( tab );
		+ initCaretParagraphListener( tab );
		+ initVariableNameInjector( tab );
		+// initSyntaxListener( tab );
		+ }
		+ }
		+ }
		+ }
		+ );
		+ }
		+
		+ /**
		+ * Reloads the preferences from the previous load.
		+ */
		+ private void initPreferences() {
		+ restoreDefinitionSource();
		+ getFileEditorPane().restorePreferences();
		+ updateDefinitionPane();
		+ }
		+
		+ /**
		+ * Listen for new tab selection events.
		+ */
		+ private void initTabChangedListener() {
		+ final FileEditorTabPane editorPane = getFileEditorPane();
		+
		+ // Update the preview pane changing tabs.
		+ editorPane.addTabSelectionListener(
		+ (ObservableValue<? extends Tab> tabPane,
		+ final Tab oldTab, final Tab newTab) -> {
		+
		+ // If there was no old tab, then this is a first time load, which
		+ // can be ignored.
		+ if( oldTab != null ) {
		+ if( newTab == null ) {
		+ closeRemainingTab();
		+ }
		+ else {
		+ // Update the preview with the edited text.
		+ refreshSelectedTab( (FileEditorTab)newTab );
		+ }
		+ }
		+ }
		+ );
		+ }
		+
		+ private void initTextChangeListener( final FileEditorTab tab ) {
		+ tab.addTextChangeListener(
		+ (ObservableValue<? extends String> editor,
		+ final String oldValue, final String newValue) -> {
		+ refreshSelectedTab( tab );
		+ }
		+ );
		+ }
		+
		+ private void initCaretParagraphListener( final FileEditorTab tab ) {
		+ tab.addCaretParagraphListener(
		+ (ObservableValue<? extends Integer> editor,
		+ final Integer oldValue, final Integer newValue) -> {
		+ refreshSelectedTab( tab );
		+ }
		+ );
		+ }
		+
		+ private void initVariableNameInjector( final FileEditorTab tab ) {
		+ VariableNameInjector.listen( tab, getDefinitionPane() );
		+ }
		+
		+ /**
		+ * Watch for changes to external files. In particular, this awaits
		+ * modifications to any XSL files associated with XML files being edited. When
		+ * an XSL file is modified (external to the application), the snitch's ears
		+ * perk up and the file is reloaded. This keeps the XSL transformation up to
		+ * date with what's on the file system.
		+ */
		+ private void initSnitch() {
		+ getSnitch().addObserver( this );
		+ }
		+
		+ /**
		+ * Called whenever the preview pane becomes out of sync with the file editor
		+ * tab. This can be called when the text changes, the caret paragraph changes,
		+ * or the file tab changes.
		+ *
		+ * @param tab The file editor tab that has been changed in some fashion.
		+ */
		+ private void refreshSelectedTab( final FileEditorTab tab ) {
		+ if( tab.isFileOpen() ) {
		+ getPreviewPane().setPath( tab.getPath() );
		+
		+ // TODO: https://github.com/DaveJarvis/scrivenvar/issues/29
		+ final Position p = tab.getCaretOffset();
		+ getLineNumberText().setText(
		+ get( STATUS_BAR_LINE,
		+ p.getMajor() + 1,
		+ p.getMinor() + 1,
		+ tab.getCaretPosition() + 1
		+ )
		+ );
		+
		+ Processor<String> processor = getProcessors().get( tab );
		+
		+ if( processor == null ) {
		+ processor = createProcessor( tab );
		+ getProcessors().put( tab, processor );
		+ }
		+
		+ try {
		+ getNotifier().clear();
		+ processor.processChain( tab.getEditorText() );
		+ } catch( final Exception ex ) {
		+ error( ex );
		+ }
		+ }
		+ }
		+
		+ /**
		+ * Returns the variable map of interpolated definitions.
		+ *
		+ * @return A map to help dereference variables.
		+ */
		+ private Map<String, String> getResolvedMap() {
		+ return getDefinitionSource().getResolvedMap();
		+ }
		+
		+ /**
		+ * Returns the root node for the hierarchical definition source.
		+ *
		+ * @return Data to display in the definition pane.
		+ */
		+ private TreeView<String> getTreeView() {
		+ try {
		+ return getDefinitionSource().asTreeView();
		+ } catch( Exception e ) {
		+ error( e );
		+ }
		+
		+ // Slightly redundant as getDefinitionSource() might have returned an
		+ // empty definition source.
		+ return (new EmptyDefinitionSource()).asTreeView();
		+ }
		+
		+ /**
		+ * Called when a definition source is opened.
		+ *
		+ * @param path Path to the definition source that was opened.
		+ */
		+ private void openDefinition( final Path path ) {
		+ try {
		+ final DefinitionSource ds = createDefinitionSource( path.toString() );
		+ setDefinitionSource( ds );
		+ storeDefinitionSource();
		+ updateDefinitionPane();
		+ } catch( final Exception e ) {
		+ error( e );
		+ }
		+ }
		+
		+ private void updateDefinitionPane() {
		+ getDefinitionPane().setRoot( getDefinitionSource().asTreeView() );
		+ }
		+
		+ private void restoreDefinitionSource() {
		+ final Preferences preferences = getPreferences();
		+ final String source = preferences.get( PREFS_DEFINITION_SOURCE, null );
		+
		+ // If there's no definition source set, don't try to load it.
		+ if( source != null ) {
		+ setDefinitionSource( createDefinitionSource( source ) );
		+ }
		+ }
		+
		+ private void storeDefinitionSource() {
		+ final Preferences preferences = getPreferences();
		+ final DefinitionSource ds = getDefinitionSource();
		+
		+ preferences.put( PREFS_DEFINITION_SOURCE, ds.toString() );
		+ }
		+
		+ /**
		+ * Called when the last open tab is closed to clear the preview pane.
		+ */
		+ private void closeRemainingTab() {
		+ getPreviewPane().clear();
		+ }
		+
		+ /**
		+ * Called when an exception occurs that warrants the user's attention.
		+ *
		+ * @param e The exception with a message that the user should know about.
		+ */
		+ private void error( final Exception e ) {
		+ getNotifier().notify( e );
		+ }
		+
		+ //---- File actions -------------------------------------------------------
		+ /**
		+ * Called when an observable instance has changed. This is called by both the
		+ * snitch service and the notify service. The snitch service can be called for
		+ * different file types, including definition sources.
		+ *
		+ * @param observable The observed instance.
		+ * @param value The noteworthy item.
		+ */
		+ @Override
		+ public void update( final Observable observable, final Object value ) {
		+ if( value != null ) {
		+ if( observable instanceof Snitch && value instanceof Path ) {
		+ final Path path = (Path)value;
		+ final FileTypePredicate predicate
		+ = new FileTypePredicate( GLOB_DEFINITION_EXTENSIONS );
		+
		+ // Reload definitions.
		+ if( predicate.test( path.toFile() ) ) {
		+ updateDefinitionSource( path );
		+ }
		+
		+ updateSelectedTab();
		+ }
		+ else if( observable instanceof Notifier && value instanceof String ) {
		+ updateStatusBar( (String)value );
		+ }
		+ }
		+ }
		+
		+ /**
		+ * Updates the status bar to show the given message.
		+ *
		+ * @param s The message to show in the status bar.
		+ */
		+ private void updateStatusBar( final String s ) {
		+ Platform.runLater(
		+ () -> {
		+ final int index = s.indexOf( '\n' );
		+ final String message = s.substring( 0, index > 0 ? index : s.length() );
		+
		+ getStatusBar().setText( message );
		+ }
		+ );
		+ }
		+
		+ /**
		+ * Called when a file has been modified.
		+ *
		+ * @param file Path to the modified file.
		+ */
		+ private void updateSelectedTab() {
		+ Platform.runLater(
		+ () -> {
		+ // Brute-force XSLT file reload by re-instantiating all processors.
		+ resetProcessors();
		+ refreshSelectedTab( getActiveFileEditor() );
		+ }
		+ );
		+ }
		+
		+ /**
		+ * Reloads the definition source from the given path.
		+ *
		+ * @param path The path containing new definition information.
		+ */
		+ private void updateDefinitionSource( final Path path ) {
		+ Platform.runLater(
		+ () -> {
		+ openDefinition( path );
		+ }
		+ );
		+ }
		+
		+ /**
		+ * After resetting the processors, they will refresh anew to be up-to-date
		+ * with the files (text and definition) currently loaded into the editor.
		+ */
		+ private void resetProcessors() {
		+ getProcessors().clear();
		+ }
		+
		+ //---- File actions -------------------------------------------------------
		+ private void fileNew() {
		+ getFileEditorPane().newEditor();
		+ }
		+
		+ private void fileOpen() {
		+ getFileEditorPane().openFileDialog();
		+ }
		+
		+ private void fileClose() {
		+ getFileEditorPane().closeEditor( getActiveFileEditor(), true );
		+ }
		+
		+ private void fileCloseAll() {
		+ getFileEditorPane().closeAllEditors();
		+ }
		+
		+ private void fileSave() {
		+ getFileEditorPane().saveEditor( getActiveFileEditor() );
		+ }
		+
		+ private void fileSaveAll() {
		+ getFileEditorPane().saveAllEditors();
		+ }
		+
		+ private void fileExit() {
		+ final Window window = getWindow();
		+ fireEvent( window, new WindowEvent( window, WINDOW_CLOSE_REQUEST ) );
		+ }
		+
		+ //---- Help actions -------------------------------------------------------
		+ private void helpAbout() {
		+ Alert alert = new Alert( AlertType.INFORMATION );
		+ alert.setTitle( get( "Dialog.about.title" ) );
		+ alert.setHeaderText( get( "Dialog.about.header" ) );
		+ alert.setContentText( get( "Dialog.about.content" ) );
		+ alert.setGraphic( new ImageView( new Image( FILE_LOGO_32 ) ) );
		+ alert.initOwner( getWindow() );
		+
		+ alert.showAndWait();
		+ }
		+
		+ //---- Convenience accessors ----------------------------------------------
		+ private float getFloat( final String key, final float defaultValue ) {
		+ return getPreferences().getFloat( key, defaultValue );
		+ }
		+
		+ private Preferences getPreferences() {
		+ return getOptions().getState();
		+ }
		+
		+ protected Scene getScene() {
		+ if( this.scene == null ) {
		+ this.scene = createScene();
		+ }
		+
		+ return this.scene;
		+ }
		+
		+ public Window getWindow() {
		+ return getScene().getWindow();
		+ }
		+
		+ private MarkdownEditorPane getActiveEditor() {
		+ final EditorPane pane = getActiveFileEditor().getEditorPane();
		+
		+ return pane instanceof MarkdownEditorPane ? (MarkdownEditorPane)pane : null;
		+ }
		+
		+ private FileEditorTab getActiveFileEditor() {
		+ return getFileEditorPane().getActiveFileEditor();
		+ }
		+
		+ //---- Member accessors ---------------------------------------------------
		+ private void setProcessors( final Map<FileEditorTab, Processor<String>> map ) {
		+ this.processors = map;
		+ }
		+
		+ private Map<FileEditorTab, Processor<String>> getProcessors() {
		+ if( this.processors == null ) {
		+ setProcessors( new HashMap<>() );
		+ }
		+
		+ return this.processors;
		+ }
		+
		+ private FileEditorTabPane getFileEditorPane() {
		+ if( this.fileEditorPane == null ) {
		+ this.fileEditorPane = createFileEditorPane();
		+ }
		+
		+ return this.fileEditorPane;
		+ }
		+
		+ private HTMLPreviewPane getPreviewPane() {
		+ if( this.previewPane == null ) {
		+ this.previewPane = createPreviewPane();
		+ }
		+
		+ return this.previewPane;
		+ }
		+
		+ private void setDefinitionSource( final DefinitionSource definitionSource ) {
		+ this.definitionSource = definitionSource;
		+ }
		+
		+ private DefinitionSource getDefinitionSource() {
		+ if( this.definitionSource == null ) {
		+ this.definitionSource = new EmptyDefinitionSource();
		+ }
		+
		+ return this.definitionSource;
		+ }
		+
		+ private DefinitionPane getDefinitionPane() {
		+ if( this.definitionPane == null ) {
		+ this.definitionPane = createDefinitionPane();
		+ }
		+
		+ return this.definitionPane;
		+ }
		+
		+ private Options getOptions() {
		+ return this.options;
		+ }
		+
		+ private Snitch getSnitch() {
		+ return this.snitch;
		+ }
		+
		+ private Notifier getNotifier() {
		+ return this.notifier;
		+ }
		+
		+ public void setMenuBar( final MenuBar menuBar ) {
		+ this.menuBar = menuBar;
		+ }
		+
		+ public MenuBar getMenuBar() {
		+ return this.menuBar;
		+ }
		+
		+ private Text getLineNumberText() {
		+ if( this.lineNumberText == null ) {
		+ this.lineNumberText = createLineNumberText();
		+ }
		+
		+ return this.lineNumberText;
		+ }
		+
		+ private synchronized StatusBar getStatusBar() {
		+ if( this.statusBar == null ) {
		+ this.statusBar = createStatusBar();
		+ }
		+
		+ return this.statusBar;
		+ }
		+
		+ //---- Member creators ----------------------------------------------------
		+ /**
		+ * Factory to create processors that are suited to different file types.
		+ *
		+ * @param tab The tab that is subjected to processing.
		+ *
		+ * @return A processor suited to the file type specified by the tab's path.
		+ */
		+ private Processor<String> createProcessor( final FileEditorTab tab ) {
		+ return createProcessorFactory().createProcessor( tab );
		+ }
		+
		+ private ProcessorFactory createProcessorFactory() {
		+ return new ProcessorFactory( getPreviewPane(), getResolvedMap() );
		+ }
		+
		+ private DefinitionSource createDefinitionSource( final String path ) {
		+ final DefinitionSource ds
		+ = createDefinitionFactory().createDefinitionSource( path );
		+
		+ if( ds instanceof FileDefinitionSource ) {
		+ try {
		+ getSnitch().listen( ((FileDefinitionSource)ds).getPath() );
		+ } catch( final IOException ex ) {
		+ error( ex );
		+ }
		+ }
		+
		+ return ds;
		}

		@Override
		public void listen( final Path file ) throws IOException {
		- if( getEavesdropped().add( file ) ) {
		+ if( file != null && getEavesdropped().add( file ) ) {
		final Path dir = toDirectory( file );
		final WatchKey key = dir.register( getWatchService(), ENTRY_MODIFY );

		@Override
		public void ignore( final Path file ) {
		- final Path directory = toDirectory( file );
		+ if( file != null ) {
		+ final Path directory = toDirectory( file );

		- // Remove all occurrences (there should be only one).
		- getWatchMap().values().removeAll( Collections.singleton( directory ) );
		+ // Remove all occurrences (there should be only one).
		+ getWatchMap().values().removeAll( Collections.singleton( directory ) );

		- // Remove all occurrences (there can be only one).
		- getEavesdropped().remove( file );
		+ // Remove all occurrences (there can be only one).
		+ getEavesdropped().remove( file );
		+ }
		}

		}

		- protected Path getPath() {
		+ public Path getPath() {
		return this.path;
		}

Added file watch on file definition source. When changed externally, the source reloads. Added null protection around snitch listen and ignore methods.