JPad 1.00(20081213)-白红宇

JPad 1.00(20081213)
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发布时间：2019-05-26
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/**
 * @author t0nsha(liaodunxia{at}gmail.com)
 * @version 1.00(20081213)
 */
import javax.print.attribute.HashPrintRequestAttributeSet;
import javax.print.attribute.PrintRequestAttributeSet;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JRadioButton;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.text.BadLocationException;
import javax.swing.undo.UndoManager;
import java.awt.BorderLayout;
import java.awt.Checkbox;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsEnvironment;
import java.awt.GridLayout;
import java.awt.List;
import java.awt.Panel;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.InputEvent;
import java.awt.event.KeyEvent;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Calendar;
publicclass JPad { 
    JFrame frame = new JFrame();
    JMenuBar menuBar = new JMenuBar();
    // JTextPane textpane = new JTextPane(); 
    JTextArea textArea = new JTextArea();
    String filepath = "";
    String filename = "Untitled";
    boolean dirty = false;
    String savedContent = "";
    String jpad = " - JPad";
    UndoManager undoManager = new UndoManager();
    StatusBar statusBar = new StatusBar();
    boolean showStatusBar = true;
class StatusBar extends JLabel { 
        /** Creates a new instance of StatusBar */
public StatusBar() { 
            super();
            super.setPreferredSize(new Dimension(100, 16));
            setMessage(Calendar.getInstance().getTime().toString());
        }
publicvoid setMessage(String message) { 
            setText(" " + message);
        }
    }
class Daemon extends Thread { 
        Daemon() { 
            setDaemon(true);
            start();
        }
publicvoid run() { 
while (true) { 
try { 
                    sleep(100);
                } catch (InterruptedException e) { 
                    throw new RuntimeException(e);
                }
                statusBar.setMessage(Calendar.getInstance().getTime()
                        .toString());
                // if (savedContent != textArea.getText()) { 
if (!savedContent.equals(textArea.getText())) { 
                    frame.setTitle("*" + filename + jpad);
                    dirty = true;
                } else { 
                    frame.setTitle(filename + jpad);
                    dirty = false;
                }
            }
        }
    }
publicclass PrintDialog implements Printable { 
        public int print(Graphics g, PageFormat pf, int page)
throws PrinterException { 
            if (page > 0) { /* We have only one page, and 'page' is zero-based */
                return NO_SUCH_PAGE;
            }
            /*
             * User (0,0) is typically outside the imageable area, so we must
             * translate by the X and Y values in the PageFormat to avoid
             * clipping
             */
            Graphics2D g2d = (Graphics2D) g;
            g2d.translate(pf.getImageableX(), pf.getImageableY());
            /* Now we perform our rendering */
            g.drawString(textArea.getText(), 100, 100);
            /* tell the caller that this page is part of the printed document */
            return PAGE_EXISTS;
        }
    }
class BrowserControl { 
        /**
         * Display a file in the system browser. If you want to display a file,
         * you must include the absolute path name.
         * 
         * @param url
         *            the file's url (the url must start with either "http://"
         *            or "file://").
         */
publicvoid displayURL(String url) { 
            boolean windows = isWindowsPlatform();
            String cmd = null;
try { 
if (windows) { 
                    // cmd = 'rundll32 url.dll,FileProtocolHandler http://...' 
                    cmd = WIN_PATH + "   " + WIN_FLAG + "   " + url;
                    Process p = Runtime.getRuntime().exec(cmd);
                } else { 
                    // Under Unix, Netscape has to be running for the "-remote" 
                    // command to work. So, we try sending the command and 
                    // check for an exit value. If the exit command is 0, 
                    // it worked, otherwise we need to start the browser. 
                    // cmd = 'netscape -remote 
                    // openURL(http://www.javaworld.com)' 
                    cmd = UNIX_PATH + "   " + UNIX_FLAG + "(" + url + ")";
                    Process p = Runtime.getRuntime().exec(cmd);
try { 
                        // wait for exit code -- if it's 0, command worked, 
                        // otherwise we need to start the browser up. 
                        int exitCode = p.waitFor();
if (exitCode != 0) { 
                            // Command failed, start up the browser 
                            // cmd = 'netscape http://www.javaworld.com' 
                            cmd = UNIX_PATH + "   " + url;
                            p = Runtime.getRuntime().exec(cmd);
                        }
                    } catch (InterruptedException x) { 
                        System.err
                                .println("Error   bringing   up   browser,   cmd='"
                                        + cmd + "'");
                        System.err.println("Caught:   " + x);
                    }
                }
            } catch (IOException x) { 
                // couldn't exec browser 
                System.err.println("Could   not   invoke   browser,   command="
                        + cmd);
                System.err.println("Caught:   " + x);
            }
        }
        /**
         * Try to determine whether this application is running under Windows or
         * some other platform by examing the "os.name" property.
         * 
         * @return true if this application is running under a Windows OS
         */
publicboolean isWindowsPlatform() { 
            String os = System.getProperty("os.name");
            if (os != null && os.startsWith(WIN_ID))
                return true;
            else
                return false;
        }
        // Used to identify the windows platform. 
        private static final String WIN_ID = "Windows";
        // The default system browser under windows. 
        private static final String WIN_PATH = "rundll32";
        // The flag to display a url. 
        private static final String WIN_FLAG = "url.dll,FileProtocolHandler";
        // The default browser under unix. 
        private static final String UNIX_PATH = "netscape";
        // The flag to display a url. 
        private static final String UNIX_FLAG = "-remote   openURL";
    }
class FontChooser extends JDialog { 
        // Results: 
        /** The font the user has chosen */
        protected Font resultFont;
        /** The resulting font name */
        protected String resultName;
        /** The resulting font size */
        protected int resultSize;
        /** The resulting boldness */
        protected boolean isBold;
        /** The resulting italicness */
        protected boolean isItalic;
        // Working fields 
        /** Display text */
        protected String displayText = "AaBbCcYyZz";
        /** The list of Fonts */
        protected String fontList[];
        /** The font name chooser */
        protected List fontNameChoice;
        /** The font size chooser */
        protected List fontSizeChoice;
        /** The bold and italic choosers */
        Checkbox bold, italic;
        /** The list of font sizes */
        protected String fontSizes[] = { "8", "10", "11", "12", "14", "16",
                "18", "20", "24", "30", "36", "40", "48", "60", "72" };
        /** The index of the default size (e.g., 14 point == 4) */
        protected static final int DEFAULT_SIZE = 4;
        /**
         * The display area. Use a JLabel as the AWT label doesn't always honor
         * setFont() in a timely fashion :-)
         */
        protected JLabel previewArea;
        /**
         * Construct a FontChooser -- Sets title and gets array of fonts on the
         * system. Builds a GUI to let the user choose one font at one size.
         */
public FontChooser(Frame f) { 
            super(f, "Font Chooser", true);
            Container cp = getContentPane();
            Panel top = new Panel();
            top.setLayout(new FlowLayout());
            fontNameChoice = new List(8);
            top.add(fontNameChoice);
            Toolkit toolkit = Toolkit.getDefaultToolkit();
            // For JDK 1.1: returns about 10 names (Serif, SansSerif, etc.) 
            // fontList = toolkit.getFontList(); 
            // For JDK 1.2: a much longer list; most of the names that come 
            // with your OS (e.g., Arial), plus the Sun/Java ones (Lucida, 
            // Lucida Bright, Lucida Sans...) 
            fontList = GraphicsEnvironment.getLocalGraphicsEnvironment()
                    .getAvailableFontFamilyNames();
            for (int i = 0; i < fontList.length; i++)
                fontNameChoice.add(fontList[i]);
            fontNameChoice.select(0);
            fontSizeChoice = new List(8);
            top.add(fontSizeChoice);
            for (int i = 0; i < fontSizes.length; i++)
                fontSizeChoice.add(fontSizes[i]);
            fontSizeChoice.select(DEFAULT_SIZE);
            cp.add(top, BorderLayout.NORTH);
            Panel attrs = new Panel();
            top.add(attrs);
            attrs.setLayout(new GridLayout(0, 1));
            attrs.add(bold = new Checkbox("Bold", false));
            attrs.add(italic = new Checkbox("Italic", false));
            previewArea = new JLabel(displayText, JLabel.CENTER);
            previewArea.setSize(200, 50);
            cp.add(previewArea, BorderLayout.CENTER);
            Panel bot = new Panel();
            JButton okButton = new JButton("Apply");
            bot.add(okButton);
            okButton.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent e) { 
                    previewFont();
                    dispose();
                    setVisible(false);
                }
            });
            JButton pvButton = new JButton("Preview");
            bot.add(pvButton);
            pvButton.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent e) { 
                    previewFont();
                }
            });
            JButton canButton = new JButton("Cancel");
            bot.add(canButton);
            canButton.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent e) { 
                    // Set all values to null. Better: restore previous. 
                    resultFont = null;
                    resultName = null;
                    resultSize = 0;
                    isBold = false;
                    isItalic = false;
                    dispose();
                    setVisible(false);
                }
            });
            cp.add(bot, BorderLayout.SOUTH);
            previewFont(); // ensure view is up to date! 
            pack();
            setLocation(100, 100);
        }
        /**
         * Called from the action handlers to get the font info, build a font,
         * and set it.
         */
protectedvoid previewFont() { 
            resultName = fontNameChoice.getSelectedItem();
            String resultSizeName = fontSizeChoice.getSelectedItem();
            int resultSize = Integer.parseInt(resultSizeName);
            isBold = bold.getState();
            isItalic = italic.getState();
            int attrs = Font.PLAIN;
            if (isBold)
                attrs = Font.BOLD;
            if (isItalic)
                attrs |= Font.ITALIC;
            resultFont = new Font(resultName, attrs, resultSize);
            // System.out.println("resultName = " + resultName + "; " + 
            // "resultFont = " + resultFont); 
            previewArea.setFont(resultFont);
            pack(); // ensure Dialog is big enough. 
        }
        /** Retrieve the selected font name. */
public String getSelectedName() { 
            return resultName;
        }
        /** Retrieve the selected size */
publicint getSelectedSize() { 
            return resultSize;
        }
        /** Retrieve the selected font, or null */
public Font getSelectedFont() { 
            return resultFont;
        }
    }
class FindReplace extends JDialog { 
        JLabel labelFindWhat = new JLabel("Find what: ");
        JLabel labelReplaceWith = new JLabel("Repalce with: ");
        JTextField textFieldFind = new JTextField();
        JTextField textFieldReplace = new JTextField();
        JButton find = new JButton("Find Next");
        JRadioButton forward = new JRadioButton("Forward");
        JRadioButton backward = new JRadioButton("Backward");
        GridLayout gridLayout = new GridLayout(4, 3);
        JButton cancel = new JButton("Cancel");
        ButtonGroup buttonGroup = new ButtonGroup();
        Checkbox caseSensitive = new Checkbox("Case sensitive");
        JButton replace = new JButton("Replace");
        int selectionStart = textArea.getCaretPosition();
        int selectionEnd = textArea.getCaretPosition();
        FindReplace(Frame owner, String title, boolean modal) { 
            super(owner, title, modal);
            this.setSize(400, 120);
            Container cp = this.getContentPane();
            cp.setLayout(gridLayout);
            buttonGroup.add(backward);
            buttonGroup.add(forward);
            cp.add(labelFindWhat);
            cp.add(textFieldFind);
            cp.add(find);
            cp.add(labelReplaceWith);
            cp.add(textFieldReplace);
            cp.add(replace);
            cp.add(backward);
            cp.add(forward);
            cp.add(cancel);
            cp.add(caseSensitive);
            pack();
            forward.setSelected(true);
            cancel.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                    FindReplace.this.setVisible(false);
                }
            });
            find.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                    int findLen = textFieldFind.getText().length();
                    int textLen = textArea.getText().length();
                    int selectionStart = textArea.getCaretPosition();
                    int selectionEnd = textArea.getCaretPosition();
                    System.out.println("selectionEnd = " + selectionEnd
                            + ", selectionEnd = " + selectionEnd);
if (caseSensitive.getState() == true) { 
if (forward.isSelected()) { 
while ((selectionStart += findLen) <= (textLen - findLen)) { 
try { 
                                    if (textArea.getText(selectionStart,
                                            findLen).equals(
                                            textFieldFind.getText())) { 
                                        selectionEnd = selectionStart + findLen;
                                        textArea.select(selectionStart,
                                                selectionEnd);
                                        break;
                                    }
                                } catch (BadLocationException e) { 
                                    // TODO Auto-generated catch block 
                                    e.printStackTrace();
                                }
                            }
                        } elseif (backward.isSelected()) { 
while ((selectionEnd -= findLen) >= findLen) { 
try { 
                                    selectionStart = selectionEnd - findLen;
                                    if (textArea.getText(selectionStart,
                                            findLen).equals(
                                            textFieldFind.getText())) { 
                                        textArea.select(selectionStart,
                                                selectionEnd);
                                        break;
                                    }
                                } catch (BadLocationException e) { 
                                    // TODO Auto-generated catch block 
                                    e.printStackTrace();
                                }
                            }
                        }
                    } elseif (caseSensitive.getState() == false) { 
if (forward.isSelected()) { 
while ((selectionStart += findLen) <= (textLen - findLen)) { 
try { 
                                    if (textArea.getText(selectionStart,
                                            findLen).toLowerCase().equals(
                                            textFieldFind.getText()
                                                    .toLowerCase())) { 
                                        selectionEnd = selectionStart + findLen;
                                        textArea.select(selectionStart,
                                                selectionEnd);
                                        break;
                                    }
                                } catch (BadLocationException e) { 
                                    // TODO Auto-generated catch block 
                                    e.printStackTrace();
                                }
                            }
                        } elseif (backward.isSelected()) { 
while ((selectionEnd -= findLen) >= findLen) { 
try { 
                                    selectionStart = selectionEnd - findLen;
                                    if (textArea.getText(selectionStart,
                                            findLen).toLowerCase().equals(
                                            textFieldFind.getText()
                                                    .toLowerCase())) { 
                                        textArea.select(selectionStart,
                                                selectionEnd);
                                        break;
                                    }
                                } catch (BadLocationException e) { 
                                    // TODO Auto-generated catch block 
                                    e.printStackTrace();
                                }
                            }
                        }
                    }
                    if ((selectionStart > (textArea.getText().length() - findLen))
                            || (selectionEnd < findLen)) { 
                        JOptionPane.showMessageDialog(FindReplace.this,
                                "Can not find /"" + textFieldFind.getText()
                                        + "/"");
                    }
                }
            });
            replace.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                    textArea.replaceSelection(textFieldReplace.getText());
                }
            });
        }
    }
boolean askSaved() { 
        boolean ret = false;
if (dirty) { 
            int option = JOptionPane.showConfirmDialog(frame,
                    "Content has been changed, do you want to save?");
if (option == JOptionPane.YES_OPTION) { 
                saveAs(false);
                ret = true;
            } elseif (option == JOptionPane.NO_OPTION) { 
                ret = true;
            }
        } else { 
            ret = true;
        }
        return ret;
    }
void saveAs(boolean isSaveAs) { 
if (isSaveAs) { 
            JFileChooser chooser = new JFileChooser();
            int returnVal = chooser.showSaveDialog(frame);
if (returnVal == JFileChooser.APPROVE_OPTION) { 
                filename = chooser.getSelectedFile().getName();
                filepath = chooser.getSelectedFile().getPath();
try { 
                    FileWriter writer = new FileWriter(filepath);
                    writer.write(textArea.getText());
                    writer.close();
                    savedContent = textArea.getText();
                } catch (IOException e) { 
                    // TODO Auto-generated catch block 
                    e.printStackTrace();
                }
            }
        } else { 
if (filepath.length() != 0) { 
try { 
                    FileWriter writer = new FileWriter(filepath);
                    writer.write(textArea.getText());
                    writer.close();
                    savedContent = textArea.getText();
                } catch (IOException e) { 
                    // TODO Auto-generated catch block 
                    e.printStackTrace();
                }
            } else { 
                JFileChooser chooser = new JFileChooser();
                int returnVal = chooser.showSaveDialog(frame);
if (returnVal == JFileChooser.APPROVE_OPTION) { 
                    filename = chooser.getSelectedFile().getName();
                    filepath = chooser.getSelectedFile().getPath();
try { 
                        FileWriter writer = new FileWriter(filepath);
                        writer.write(textArea.getText());
                        writer.close();
                        savedContent = textArea.getText();
                    } catch (IOException e) { 
                        // TODO Auto-generated catch block 
                        e.printStackTrace();
                    }
                }
            }
        }
        frame.setTitle(filename + jpad);
    }
void open() { 
        JFileChooser chooser = new JFileChooser();
        int returnVal = chooser.showOpenDialog(frame);
if (returnVal == JFileChooser.APPROVE_OPTION) { 
            filepath = chooser.getSelectedFile().getPath();
            filename = chooser.getSelectedFile().getName();
try { 
                int offset = 0;
                int length = (int) (new File(filepath)).length();
                char[] cbuf = new char[length];
                FileReader reader = new FileReader(filepath);
while (reader.ready()) { 
                    reader.read(cbuf, offset, length);
                }
                reader.close();
                textArea.setText(new String(cbuf));
                savedContent = new String(cbuf);
            } catch (FileNotFoundException e) { 
                // TODO Auto-generated catch block 
                e.printStackTrace();
            } catch (IOException e) { 
                // TODO Auto-generated catch block 
                e.printStackTrace();
            }
        }
        frame.setTitle(filename + jpad);
    }
void jnew() { 
        savedContent = "";
        textArea.setText("");
        filename = "Untitled";
        frame.setTitle(filename + jpad);
    }
class FrameL implements WindowListener { 
        @Override
publicvoid windowActivated(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
        @Override
publicvoid windowClosed(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
        @Override
publicvoid windowClosing(WindowEvent e) { 
            // TODO Auto-generated method stub 
if (dirty) { 
if (askSaved()) { 
                    System.exit(0);
                }
            } else { 
                System.exit(0);
            }
        }
        @Override
publicvoid windowDeactivated(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
        @Override
publicvoid windowDeiconified(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
        @Override
publicvoid windowIconified(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
        @Override
publicvoid windowOpened(WindowEvent e) { 
            // TODO Auto-generated method stub 
        }
    }
public JPad() { 
        new Daemon();
        textArea.setText("");
        frame.setTitle(filename + jpad);
        frame.setSize(640, 480);
        // add close handle 
        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        frame.addWindowListener(new FrameL());
        // add menu fileMenu 
        JMenu fileMenu = new JMenu("File");
        fileMenu.setMnemonic('F'); // make 'F' underlined. 
        menuBar.add(fileMenu);
        // add menu item fileMenu --> new 
        JMenuItem fileNew = new JMenuItem("New", 'N');
        fileNew.setAccelerator(KeyStroke.getKeyStroke('N',
                InputEvent.CTRL_MASK, true));
        fileNew.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu new"); 
if (askSaved()) { 
                    jnew();
                }
            }
        });
        fileMenu.add(fileNew);
        // add menu item fileMenu --> open 
        JMenuItem fileOpen = new JMenuItem("Open...", 'O');
        fileOpen.setAccelerator(KeyStroke.getKeyStroke('O',
                InputEvent.CTRL_MASK, true));
        fileOpen.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu open"); 
if (askSaved()) { 
                    open();
                }
            }
        });
        fileMenu.add(fileOpen);
        // add menu item fileMenu --> save 
        JMenuItem fileSave = new JMenuItem("Save", 'S');
        fileSave.setAccelerator(KeyStroke.getKeyStroke('S',
                InputEvent.CTRL_MASK, true));
        fileSave.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu save"); 
                saveAs(false);
            }
        });
        fileMenu.add(fileSave);
        // add menu item fileMenu --> save as 
        JMenuItem fileSaveAs = new JMenuItem("Save As...", 'A');
        fileSaveAs.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu save as"); 
                saveAs(true);
            }
        });
        fileMenu.add(fileSaveAs);
        // add menu item fileMenu --> separator 
        fileMenu.addSeparator();
        // add menu item fileMenu --> print 
        JMenuItem filePrint = new JMenuItem("Print...", 'P');
        filePrint.setAccelerator(KeyStroke.getKeyStroke('P',
                InputEvent.CTRL_MASK, true));
        filePrint.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu print"); 
try { 
                    String cn = UIManager.getSystemLookAndFeelClassName();
                    UIManager.setLookAndFeel(cn); // Use the native L&F 
                } catch (Exception cnf) { 
                }
                PrinterJob job = PrinterJob.getPrinterJob();
                PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
                PageFormat pf = job.pageDialog(aset);
                job.setPrintable(new PrintDialog(), pf);
                boolean ok = job.printDialog(aset);
if (ok) { 
try { 
                        job.print(aset);
                    } catch (PrinterException ex) { 
                        /* The job did not successfully complete */
                    }
                }
            }
        });
        fileMenu.add(filePrint);
        // add menu item fileMenu --> separator 
        fileMenu.addSeparator();
        // add menu item fileMenu --> exit 
        JMenuItem fileExit = new JMenuItem("Exit", 'X');
        fileExit.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "fileMenu exit"); 
if (askSaved()) { 
                    System.exit(0);
                }
            }
        });
        fileMenu.add(fileExit);
        // add menu edit 
        JMenu editMenu = new JMenu("Edit");
        editMenu.setMnemonic('E');
        menuBar.add(editMenu);
        // add menu item edit --> undo typing 
        JMenuItem editUndoTyping = new JMenuItem("Undo Typing", 'U');
        editUndoTyping.setAccelerator(KeyStroke.getKeyStroke('Z',
                InputEvent.CTRL_MASK, true));
        editUndoTyping.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
if (undoManager.canUndo()) { 
                    undoManager.undo();
                }
            }
        });
        editMenu.add(editUndoTyping);
        // add menu item edit --> separator 
        editMenu.addSeparator();
        // add menu item edit --> cut 
        JMenuItem editCut = new JMenuItem("Cut", 'T');
        editCut.setAccelerator(KeyStroke.getKeyStroke('X',
                InputEvent.CTRL_MASK, true));
        editCut.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.cut();
            }
        });
        editMenu.add(editCut);
        // add menu item edit --> copy 
        JMenuItem editCopy = new JMenuItem("Copy", 'C');
        editCopy.setAccelerator(KeyStroke.getKeyStroke('C',
                InputEvent.CTRL_MASK, true));
        editCopy.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.copy();
            }
        });
        editMenu.add(editCopy);
        // add menu item edit --> paste 
        JMenuItem editPaste = new JMenuItem("Paste", 'P');
        editPaste.setAccelerator(KeyStroke.getKeyStroke('V',
                InputEvent.CTRL_MASK, true));
        editPaste.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.paste();
            }
        });
        editMenu.add(editPaste);
        // add menu item edit --> delete 
        JMenuItem editDelete = new JMenuItem("Delete", 'L');
        editDelete
                .setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_DELETE, 0));
        editDelete.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.replaceSelection(null);
            }
        });
        editMenu.add(editDelete);
        // add menu item edit --> separator 
        editMenu.addSeparator();
        // add menu item edit --> find 
        JMenuItem editFind = new JMenuItem("Find/Replace...", 'F');
        editFind.setAccelerator(KeyStroke.getKeyStroke('F',
                InputEvent.CTRL_MASK, true));
        editFind.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "edit find"); 
                FindReplace findReplace = new FindReplace(frame, "Find", false);
                findReplace.setVisible(true);
            }
        });
        editMenu.add(editFind);
        // add menu item edit --> go to 
        JMenuItem editGoto = new JMenuItem("Go To...", 'G');
        editGoto.setAccelerator(KeyStroke.getKeyStroke('G',
                InputEvent.CTRL_MASK, true));
        editGoto.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
if (!textArea.getLineWrap()) { 
                    String s = JOptionPane.showInputDialog(null,
                            "Line number: ", "Go to the following row",
                            JOptionPane.QUESTION_MESSAGE);
                    // press Cancel will raise a NullPointerException 
if (s != null) { 
try { 
                            int i = Integer.parseInt(s);
if (i > textArea.getLineCount()) { 
                                JOptionPane.showMessageDialog(null,
                                        "Row out of range.", "JPad - Go To",
                                        JOptionPane.NO_OPTION);
                            } else { 
                                textArea.setCaretPosition(textArea.getText()
                                        .indexOf("/n", i - 1) + 1);
                            }
                        } catch (NumberFormatException nfe) { 
                            JOptionPane.showMessageDialog(null,
                                    "Invalid Number!");
                        }
                    }
                } else { 
                    JOptionPane.showMessageDialog(null,
                            "Please turn off auto wrap first!");
                }
            }
        });
        editMenu.add(editGoto);
        // add menu item separator 
        editMenu.addSeparator();
        // add menu item edit --> select all 
        JMenuItem editSelectAll = new JMenuItem("Select All", 'A');
        editSelectAll.setAccelerator(KeyStroke.getKeyStroke('A',
                InputEvent.CTRL_MASK, true));
        editSelectAll.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.selectAll();
            }
        });
        editMenu.add(editSelectAll);
        // add menu item edit --> time date 
        JMenuItem editTimeDate = new JMenuItem("Time/Date", 'D');
        editTimeDate.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F5, 0));
        editTimeDate.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.replaceSelection(Calendar.getInstance().getTime()
                        .toString());
            }
        });
        editMenu.add(editTimeDate);
        // add menu option 
        JMenu optionMenu = new JMenu("Option");
        optionMenu.setMnemonic('O');
        menuBar.add(optionMenu);
        // add menu item option --> auto wrap 
        JMenuItem optionAutoWrap = new JMenuItem("Auto Wrap", 'W');
        optionAutoWrap.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                textArea.setLineWrap(!textArea.getLineWrap());
            }
        });
        optionMenu.add(optionAutoWrap);
        // add menu item option --> auto wrap 
        JMenuItem optionFont = new JMenuItem("Font...", 'F');
        optionFont.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                // JOptionPane.showMessageDialog(null, "option font"); 
                FontChooser fc = new FontChooser(frame);
                fc.setVisible(true);
                Font f = fc.getSelectedFont();
                textArea.setFont(f);
            }
        });
        optionMenu.add(optionFont);
        // add menu view 
        JMenu viewMenu = new JMenu("View");
        viewMenu.setMnemonic('V');
        menuBar.add(viewMenu);
        // add menu item view --> status bar 
        JMenuItem viewStatusBar = new JMenuItem("Status Bar", 'S');
        viewStatusBar.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                showStatusBar = !showStatusBar;
                statusBar.setVisible(showStatusBar);
            }
        });
        viewMenu.add(viewStatusBar);
        // add menu help 
        JMenu helpMenu = new JMenu("Help");
        helpMenu.setMnemonic('H');
        menuBar.add(helpMenu);
        // add menu item help --> help contents 
        JMenuItem helpContents = new JMenuItem("Help Contents", 'H');
        helpContents.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                BrowserControl bc = new BrowserControl();
                bc.displayURL("http://blog.csdn.net/t0nsha");
            }
        });
        helpMenu.add(helpContents);
        // add menu item separator 
        helpMenu.addSeparator();
        // add menu item help --> about jpad 
        JMenuItem helpAboutJPad = new JMenuItem("About JPad", 'A');
        helpAboutJPad.addActionListener(new ActionListener() { 
publicvoid actionPerformed(ActionEvent ae) { 
                JOptionPane
                        .showMessageDialog(
                                null,
                                "version 1.00(20081213)/n(c) t0nsha/nliaodunxia{at}gmail.com",
                                "About JPad", JOptionPane.INFORMATION_MESSAGE);
            }
        });
        helpMenu.add(helpAboutJPad);
        // add menu bar 
        frame.setJMenuBar(menuBar);
        frame.getContentPane().add(statusBar, BorderLayout.SOUTH);
        // add text area 
        textArea.getDocument().addUndoableEditListener(undoManager);
        frame.add(new JScrollPane(textArea));
        frame.setVisible(true);
    }
publicstaticvoid main(String[] args) { 
        new JPad();
    }
}