View Javadoc
   package com.bonevich.erj.ui;
   
   import com.bonevich.erj.ErjConstants;
   import com.bonevich.erj.app.Project;
   import com.bonevich.util.ResourceUtilities;
   
   import org.tigris.gef.base.*;
   
   import java.awt.*;
  import java.awt.event.*;
  import javax.swing.*;
  import javax.swing.event.*;
  import java.util.*;
  import java.io.*;
  
  /***
   * An abstract button command class.
   * @author jbonevic
   */
  public abstract class Command extends AbstractAction
  {
  	//////////////////////////////////////////////////////////
  	// Constants
  	public static final boolean IS_GLOBAL  = true;
  	public static final boolean NOT_GLOBAL = false;
  
  	//////////////////////////////////////////////////////////
  	// Attributes
  	protected static CommandManager _manager = new CommandManager();
  
  	protected boolean _modifiesProject = false;
  
  	//////////////////////////////////////////////////////////
  	// Command instances
  
  	// File Menu
  	public static Command NewProject = new CommandNewProject();
  	public static Command NewDiagram = new CommandNewDiagram();
  	public static Command Open       = new CommandOpen();
  	public static Command Save       = new CommandSave();
  	public static Command SaveAs     = new CommandSaveAs();
  	public static Command Print      = new CommandPrint();
  	public static Command PageSetup  = new CommandPageSetup();
  	public static Command Exit       = new CommandExit();
  
  	// Edit Menu
  	public static Command Undo       = new CommandUndo();
  	public static Command Redo       = new CommandRedo();
  	public static Command Cut        = new CommandCut();
  	public static Command Copy       = new CommandCopy();
  	public static Command Paste      = new CommandPaste();
  	public static Command Delete     = new CommandDelete();
  	public static Command SelectAll  = new CommandSelectAll();
  	public static Command Remove     = new CommandRemove();
  	public static Command History    = new CommandHistory();
  	public static Command Prefs      = new CommandPrefs();
  
  	// View Menu
  	public static Command Zoom       = new CommandZoom();
  	public static Command ZoomIn     = new CommandZoomIn();
  	public static Command ZoomOut    = new CommandZoomOut();
  	public static Command Goto       = new CommandGoto();
  	public static Command AdjustGrid = new CommandAdjustGrid();
  	public static Command AdjustSnap = new CommandAdjustSnap();
  	public static Command AdjustPageBreak = new CommandAdjustPageBreak();
  
  	// Project Menu
  	public static Command TargetDatabase = new CommandTargetDatabase();
  	public static Command ProjectProps   = new CommandProjectProps();
  
  	// Tools Menu
  	public static Command Generate    = new CommandGenerate();
  	public static Command Synchronize = new CommandSynchronize();
  	public static Command Arrange     = new CommandArrange();
  
  	// Help Menu
  	public static Command Contents = new CommandContents();
  	public static Command About    = new CommandAbout();
  
  	// Diagram Pane Popup
  	public static Command DeleteDiagram   = new CommandDeleteDiagram();
  	public static Command RenameDiagram   = new CommandRenameDiagram();
  	public static Command ReorderDiagrams = new CommandReorderDiagrams();
  
  	//////////////////////////////////////////////////////////
  	// Constructors
  	public Command(String name)
  	{
  		this(name, IS_GLOBAL);
  	}
  
  	public Command(String name, boolean isGlobal)
  	{
  		super(name);
  		if (isGlobal)
  		{
  			_manager.register(this);
  		}
  		putValue(Action.SHORT_DESCRIPTION, name);
 		updateEnabled();
 	}
 
 	//////////////////////////////////////////////////////////
 	// Operations
 	public void actionPerformed(ActionEvent e)
 	{
 		invoke();
 	}
 	
 	public void invoke()
 	{
 		// manager will call doIt(), etc.
 		_manager.invoke(this);
 		if (_modifiesProject)
 		{
 			markProjectModified();
 		}
 	}
 
 	public abstract boolean doIt();
 
 	public abstract void undoIt();
 
 	/*** Mark the current project as out-of-date. */
 	public void markProjectModified()
 	{
 		ErjFrame browser = ErjFrame.getInstance();
 		Project p = browser.getApplication().getCurrentProject();
 		p.markAsModified();
 	}
 
 	protected void setModifiesProject(boolean modifies)
 	{
 		_modifiesProject = modifies;
 	}
 	
 	public void updateEnabled()
 	{
 		setEnabled(shouldBeEnabled());
 	}
 
 	public boolean shouldBeEnabled()
 	{
 		return true;
 	}
 
 	public String getName()
 	{
 		return (String) getValue(NAME);
 	}
 	public void setName(String name)
 	{
 		putValue(NAME, name);
 	}
 
 	public static void updateAllEnabled()
 	{
 		_manager.updateAllRegisteredCommands();
 	}
 
 	public JButton getButton()
 	{
 		JButton button = new JButton(this);
 		button.setText(ErjConstants.EMPTY_STR);
 		button.setMargin(new Insets(0,0,0,0));
 		button.setIcon(
 			new ImageIcon(
 				ResourceUtilities.getResourceAsURL(
 					"com/bonevich/erj/images/general/" + getIconName() + ".gif"
 				)
 			)
 		);
 		return button;
 	}
 
 	protected String getIconName() { return null; }
 
 
 	/***
 	 * Command to open a project from a specified file
 	 * in the history.
 	 * Had to make this an inner class to get rid of annoying
 	 * compile-time warnings.
 	 */
 	static class CommandOpenFromHistory extends Command
 	{
 		private String _filepath = null;
 
 		public CommandOpenFromHistory(String filepath)
 		{
 			super(ErjConstants.EMPTY_STR);
 			_filepath = filepath;
 		}
 
 		public boolean doIt()
 		{
 			if (SaveProjectConfirm.confirm())
 			{
 				ErjFrame frame = ErjFrame.getInstance();
 				frame.getApplication().loadProject(_filepath);
 				frame.getFileHistory().insertPathname(_filepath);
 			}
 			
 			return false;
 		}
 
 		public void undoIt() { }
 	} /* end class CommandOpenFromHistory */
 	
 } /* end class Command */
 
 
 //////////////////////////////////////////////////////////
 // Convenient Command classes
 
 /***
  * Command to create a new project.  Also confirms that the current
  * project has been saved before trashing it.
  */
 class CommandNewProject extends Command
 {
 	public CommandNewProject() { super("Project..."); }
 
 	public boolean doIt()
 	{
 		if (SaveProjectConfirm.confirm())
 		{
 			ErjFrame frame = ErjFrame.getInstance();
 			Project newProject = frame.getApplication().createDefaultProject();
 			JDialog props = new ProjectPropertiesDialog(newProject);
 			props.show();
 		}
 		return false;
 	}
 
 	public void undoIt() { }
 
 	protected String getIconName() { return "New16"; }
 } /* end class CommandNewProject */
 
 
 /***
  * Command to create a new diagram in the current project 
  */
 class CommandNewDiagram extends Command
 {
 	public CommandNewDiagram()
 	{
 		super("Insert Diagram...");
 		setModifiesProject(true);
 	}
 
 	public boolean doIt()
 	{
 		//FIXME: we should create an editor so you can set name, etc.
 		ErjFrame browser = ErjFrame.getInstance();
 		Project project = browser.getApplication().getCurrentProject();
 		project.createDiagram();
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandNewDiagram */
 
 
 /***
  * Abstract Command subclassed by CommandOpen and CommandSaveAs so
  * that they may share an instance of JFileChooser.  Also means that
  * the chooser will remember the "current working directory" 
  * between uses.
  */
 abstract class CommandFileChooser extends Command
 {
 	protected JFileChooser _chooser = new JFileChooser();
 
 	public CommandFileChooser(String name) { super(name); }
 
 } /* end class CommandFileChooser */
 
 
 /***
  * Command to open an existing project.  Confirms that the current
  * project needs to be saved.
  */
 class CommandOpen extends CommandFileChooser
 {
 	public CommandOpen() { super("Open..."); }
 
 	public boolean doIt()
 	{
 		if (SaveProjectConfirm.confirm())
 		{
 			_chooser.addChoosableFileFilter(ErjFileFilter.ERJ);
 			_chooser.addChoosableFileFilter(ErjFileFilter.SQL);
 			_chooser.addChoosableFileFilter(ErjFileFilter.SVG);
 			_chooser.setFileFilter(ErjFileFilter.ERJ);
 			int choice = _chooser.showOpenDialog(null);
 			if (choice == JFileChooser.APPROVE_OPTION)
 			{
 				File projectFile = _chooser.getSelectedFile();
 				String filepath = projectFile.getAbsolutePath();
 
 				ErjFrame frame = ErjFrame.getInstance();
 				frame.getApplication().loadProject(filepath);
 				frame.getFileHistory().insertPathname(filepath);
 			}
 		}
 		
 		return false;
 	}
 
 	public void undoIt() { }
 
 	protected String getIconName() { return "Open16"; }
 } /* end class CommandOpen */
 
 
 /***
  * Command to save the current project 
  */
 class CommandSave extends Command
 {
 	public CommandSave() { super("Save"); }
 
 	public boolean doIt()
 	{
 		ErjFrame frame = ErjFrame.getInstance();
 		Project p = frame.getApplication().getCurrentProject();
 		//System.err.println("project status = " + (p.isNew() ? "new" : "saved") + 
 		//									 ", " + (p.isModified() ? "modified" : "clean"));
 		if (p.isNew())
 		{
 			Command.SaveAs.invoke();
 		}
 		else
 		{
 			p.save();
 		}
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled()
 	{
 		ErjFrame frame = ErjFrame.getInstance();
 		if (frame.isVisible())
 		{
 			Project p = frame.getApplication().getCurrentProject();
 			if (p != null)
 			{
 				return p.isNew() || p.isModified();
 			}
 		}
 		return false;
 	}
 
 	protected String getIconName() { return "Save16"; }
 } /* end class CommandSave */
 
 
 /***
  * Command to save the current project under a new filename
  * and/or in a different format 
  */
 class CommandSaveAs extends CommandFileChooser
 {
 	public CommandSaveAs() { super("Save As..."); }
 
 	public boolean doIt()
 	{
 		ErjFrame frame = ErjFrame.getInstance();
 		Project p = frame.getApplication().getCurrentProject();
 		File path = new File(p.getFilepath());
 		_chooser.setCurrentDirectory(path);
 		_chooser.addChoosableFileFilter(ErjFileFilter.ERJ);
 		_chooser.addChoosableFileFilter(ErjFileFilter.UML);
 		_chooser.addChoosableFileFilter(ErjFileFilter.SQL);
 		_chooser.addChoosableFileFilter(ErjFileFilter.SVG);
 		_chooser.addChoosableFileFilter(ErjFileFilter.GIF);
 		_chooser.setFileFilter(ErjFileFilter.ERJ);
 		int choice = _chooser.showSaveDialog(null);
 		if (choice == JFileChooser.APPROVE_OPTION)
 		{
 			File projectFile = _chooser.getSelectedFile();
 			String filepath = projectFile.getAbsolutePath();
 			p.save(filepath);
 			frame.getFileHistory().insertPathname(p.getFilepath());
 		}
 		return false;
 	}
 
 	public void undoIt() { }
 
 	protected String getIconName() { return "SaveAs16"; }
 } /* end class CommandSaveAs */
 
 
 /***
  * Command to print diagram(s) 
  */
 class CommandPrint extends Command
 {
 	public CommandPrint() { super("Print..."); }
 
 	public boolean doIt()
 	{
 		//FIXME: reimplement using java.awt.print library
 		CmdPrint cmd = new CmdPrint();
 		ErjFrame browser = ErjFrame.getInstance();
 		Diagram diagram = browser.getActiveDiagram();
 		cmd.setDiagramName(diagram.getName());
 		cmd.doIt();
 		
 		return false;
 	}
 
 	public void undoIt() { }
 
 	protected String getIconName() { return "Print16"; }
 } /* end class CommandPrint */
 
 
 /***
  * Command to change the current page settings 
  */
 class CommandPageSetup extends Command
 {
 	public CommandPageSetup() { super("Page Setup..."); }
 
 	public boolean doIt()
 	{
 		//FIXME: reimplement using java.awt.print library
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 
 	protected String getIconName() { return "PageSetup16"; }
 } /* end class CommandPageSetup */
 
 
 /***
  * Command to exit the application
  */
 class CommandExit extends Command
 {
 	public CommandExit() { super("Exit"); }
 
 	public boolean doIt()
 	{
 		// check if the current project needs saving
 		if (SaveProjectConfirm.confirm())
 		{
 			ErjFrame.getInstance().exit();
 		}
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandExit */
 
 
 /***
  * Command to remove the currently selected figure(s) from the
  * active editor, placing a copy in the application clipboard,
  * but not remove them from the model.
  */
 class CommandCut extends Command
 {
 	public CommandCut() { super("Cut"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 
 	protected String getIconName() { return "Cut16"; }
 } /* end class CommandCut */
 
 
 /***
  * Command to copy the currently selected figure(s) from the
  * active editor to the application clipboard.
  */
 class CommandCopy extends Command
 {
 	public CommandCopy() { super("Copy"); }
 
 	public boolean doIt()
 	{
 		Vector figs = getSelections();
 		if (figs.isEmpty())
 		{
 			return false;
 		}
 		//Transferable object = new TransferableFigSelection(figs);
 		//ErjFrame.getInstance().getClipboard().setContents(object, object);
 		return true;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled()
 	{
 		Vector figs = getSelections();
 		if (! (figs != null && !figs.isEmpty()) )
 		{
 			return false;
 		}
 		return true;
 	}
 
 	private Vector getSelections()
 	{
 		Editor editor = Globals.curEditor();
 		if (editor == null)
 		{
 			return new Vector();
 		}
 		SelectionManager sm = editor.getSelectionManager();
 		return sm.getFigs();
 	}
 
 	protected String getIconName() { return "Copy16"; }
 } /* end class CommandCopy */
 
 
 /***
  * Command to paste the contents of the application clipboard
  * into the currently active editor.  Automatically places the
  * figures.
  */
 class CommandPaste extends Command
 {
 	public CommandPaste() { super("Paste"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 
 	protected String getIconName() { return "Paste16"; }
 } /* end class CommandPaste */
 
 
 /***
  * Command to remove the currently selected figure(s) from the
  * active editor, but not from the model. Copies are not saved
  * in the application clipboard.
  */
 class CommandDelete extends Command
 {
 	public CommandDelete() { super("Delete"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandDelete */
 
 
 /***
  * Command to cause all figures in the active editor to be
  * selected.
  */
 class CommandSelectAll extends Command
 {
 	public CommandSelectAll() { super("Select All"); }
 
 	public boolean doIt()
 	{
 		Editor editor = Globals.curEditor();
 		if (editor == null)
 		{
 			return false;
 		}
 		SelectionManager sm = editor.getSelectionManager();
 		sm.select(editor.getLayerManager().getActiveLayer().getContents());
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandSelectAll */
 
 
 /*** 
  * Command to remove the currently selected figure(s) from the
  * active editor and the model. Copies are not saved in the
  * application clipboard.
  */
 class CommandRemove extends Command
 {
 	public CommandRemove() { super("Remove From Model"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandRemove */
 
 
 /***
  * Command to view the application project file history, and
  * to open an editor on it.
  */
 class CommandHistory extends Command
 {
 	public CommandHistory() { super("History..."); }
 
 	public boolean doIt()
 	{
 		ErjFrame.getInstance().getFileHistory().processList();
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandHistory */
 
 
 /***
  * Command to open an editor on the application preferences.
  */
 class CommandPrefs extends Command
 {
 	public CommandPrefs() { super("Preferences..."); }
 
 	public boolean doIt()
 	{
 		Cmd cmd = new CmdOpenWindow(
 		                        	"org.tigris.gef.base.PrefsEditor", 
 		                        	"Preferences..."
 		                        );
 		cmd.doIt();
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandPrefs */
 
 
 /***
  * Command to zoom the diagram on the current editor to
  * a desired factor.
  */
 class CommandZoom extends Command
 {
 	public CommandZoom() { super("Zoom..."); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandZoom */
 
 
 /***
  * Command to zoom the diagram in one increment on the current editor.
  */
 class CommandZoomIn extends Command
 {
 	public CommandZoomIn() { super("Zoom In"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 
 	protected String getIconName() { return "ZoomIn16"; }
 } /* end class CommandZoomIn */
 
 
 /***
  * Command to zoom the diagram out one increment on the current editor.
  */
 class CommandZoomOut extends Command
 {
 	public CommandZoomOut() { super("Zoom Out"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 
 	protected String getIconName() { return "ZoomOut16"; }
 } /* end class CommandZoomOut */
 
 
 /***
  * Command to go to the editor with a selected relation.
  */
 class CommandGoto extends Command
 {
 	public CommandGoto() { super("Goto"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandGoto */
 
 
 /***
  * Command to adjust the grid size on the current editor.
  */
 class CommandAdjustGrid extends Command
 {
 	public CommandAdjustGrid() { super("Adjust Grid"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandAdjustGrid */
 
 
 /***
  * Command to adjust the grid snap on the current editor.
  */
 class CommandAdjustSnap extends Command
 {
 	public CommandAdjustSnap() { super("Adjust Snap"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandAdjustSnap */
 
 
 /***
  * Command to adjust the page breaks on the current editor.
  */
 class CommandAdjustPageBreak extends Command
 {
 	public CommandAdjustPageBreak() { super("Adjust Page Break"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandAdjustPageBreak */
 
 
 /***
  * Command to select a target database and define login parameters.
  */
 class CommandTargetDatabase extends Command
 {
 	public CommandTargetDatabase() { super("Target Database..."); }
 
 	public boolean doIt()
 	{
 		Project p = ErjFrame.getInstance().getApplication().getCurrentProject();
 		TargetDatabaseDialog dialog = new TargetDatabaseDialog(p);
 		dialog.show();
 		return false;
 	}
 
 	public void undoIt() { }
 
 } /* end class CommandTargetDatabase */
 
 
 /***
  * Command to bring up an editor on the project properties.
  */
 class CommandProjectProps extends Command
 {
 	public CommandProjectProps()
 	{
 		super("Project Properties...");
 		//Project takes care of modification flagging itself
 		//setModifiesProject();
 	}
 
 	public boolean doIt()
 	{
 		Project p = ErjFrame.getInstance().getApplication().getCurrentProject();
 		ProjectPropertiesDialog dialog = new ProjectPropertiesDialog(p);
 		dialog.show();
 		return false;
 	}
 
 	public void undoIt() { }
 
 } /* end class CommandProjectProps */
 
 
 /***
  * Command to generate SQL DDL scripts from a model.
  */
 class CommandGenerate extends Command
 {
 	public CommandGenerate() { super("Generate..."); }
 
 	public boolean doIt()
 	{
 		Project p = ErjFrame.getInstance().getApplication().getCurrentProject();
 		GenerateDDLDialog dialog = new GenerateDDLDialog(p);
 		dialog.show();
 		return false;
 	}
 
 	public void undoIt() { }
 
 } /* end class CommandGenerate */
 
 
 /***
  * Command to synchronize the current model with an actual
  * database schema.
  */
 class CommandSynchronize extends Command
 {
 	public CommandSynchronize() { super("Synchronize..."); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandSynchronize */
 
 
 /***
  * Command to auto-arrange figures in the current editor.
  */
 class CommandArrange extends Command
 {
 	public CommandArrange() { super("Arrange"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandArrange */
 
 
 /***
  * Command to bring up ERJ help.
  */
 class CommandContents extends Command
 {
 	public CommandContents() { super("Contents"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandContents */
 
 
 /***
  * Command to bring up information about ERJ.
  */
 class CommandAbout extends Command
 {
 	public CommandAbout() { super("About"); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandAbout */
 
 
 /***
  * Command to delete the currently selected diagram tab.
  * Note: this does not remove anything from the underlying
  * information model.
  */
 class CommandDeleteDiagram extends Command
 {
 	public CommandDeleteDiagram() { super("Delete Diagram"); }
 
 	public boolean doIt()
 	{
 		// confirm that they really, really want to do this
 		ErjFrame browser = ErjFrame.getInstance();
 		String confirm = "Deleting a diagram cannot be undone.\n\nAre You Sure?";
 		Object[] options = {"OK", "Cancel"};
 		int rez = JOptionPane.showOptionDialog(
 			browser, confirm, "Warning", JOptionPane.DEFAULT_OPTION,
 			JOptionPane.WARNING_MESSAGE, null, options, options[0]
 		);
 		if (rez == JOptionPane.YES_OPTION)
 		{
 			browser.deleteActiveDiagram();
 			setModifiesProject(true);
 		}
 		else
 		{
 			setModifiesProject(false);
 		}
 		return false;
 	}
 
 	public void undoIt() { }
 } /* end class CommandDeleteDiagram */
 
 
 /***
  * Command to rename a diagram, and thus update its
  * diagram tab title.
  */
 class CommandRenameDiagram extends Command
 {
 	private boolean _canUndo = false;
 	private JTextField _tf = new JTextField(20);
 	private JButton _okButton = new JButton("Ok");
 	private JButton _cancelButton = new JButton("Cancel");
 	private JDialog _dialog;
 	{
 		ErjFrame browser = ErjFrame.getInstance();
 		String msg = "Rename Diagram";
 		_dialog = new JDialog(browser, msg, true);
 		_dialog.setResizable(false);
 		JPanel buttons = new JPanel();
 		buttons.add(_okButton);
 		buttons.add(_cancelButton);
 		Container content = _dialog.getContentPane();
 		content.add(_tf, BorderLayout.CENTER);
 		content.add(buttons, BorderLayout.SOUTH);
 		addActionListeners();
 		_dialog.pack();
 		_dialog.setLocationRelativeTo(browser);
 	}
 
 	public CommandRenameDiagram() { super("Rename Diagram"); }
 
 	public boolean doIt()
 	{
 		ErjFrame browser = ErjFrame.getInstance();
 		_tf.setText(browser.getActiveDiagram().getName());
 		_dialog.show();
 		return _canUndo;
 	}
 
 	private void addActionListeners()
 	{
 		_okButton.addActionListener(
 			new ActionListener()
 			{
 				public void actionPerformed(ActionEvent e)
 				{
 					ErjFrame browser = ErjFrame.getInstance();
 					Diagram diagram = browser.getActiveDiagram();
 					try {
 						diagram.setName(_tf.getText());
 					} catch (Exception err) {}
 					CommandRenameDiagram.this.setModifiesProject(true);
 					CommandRenameDiagram.this._canUndo = true;
 					_dialog.dispose();
 				}
 			}
 		);
 		_cancelButton.addActionListener(
 			new ActionListener()
 			{
 				public void actionPerformed(ActionEvent e)
 				{
 					CommandRenameDiagram.this.setModifiesProject(false);
 					CommandRenameDiagram.this._canUndo = false;
 					_dialog.dispose();
 				}
 			}
 		);
 	}
 
 	public void undoIt() { }
 } /* end class CommandRenameDiagram */
 
 
 /***
  * Command to re-define the order of diagrams in a project.
  */
 class CommandReorderDiagrams extends Command
 {
 	public CommandReorderDiagrams() { super("Reorder Diagrams..."); }
 
 	public boolean doIt()
 	{
 		return false;
 	}
 
 	public void undoIt() { }
 
 	public boolean shouldBeEnabled() { return false; }
 } /* end class CommandReorderDiagrams */
 
 
 //////////////////////////////////////////////////////////
 // Useful cross-command components
 /***
  * Confirm whether to save a modified project.
  */
 class SaveProjectConfirm
 {
 	public static boolean confirm()
 	{
 		ErjFrame browser = ErjFrame.getInstance();
 		Project p = browser.getApplication().getCurrentProject();
 		if (p.isModified())
 		{
 			String confirm = "Save changes to " + p.getName();
 			int rez = JOptionPane.showConfirmDialog(
 				browser, confirm, confirm, JOptionPane.YES_NO_CANCEL_OPTION);
 			if (rez == JOptionPane.CANCEL_OPTION)
 			{
 				return false;
 			}
 			else if (rez == JOptionPane.YES_OPTION)
 			{
 				Command.Save.invoke();
 				return true;
 			}
 		}
 		return true;
 	}
 } /* end class SaveProjectConfirm */