private void sort(int column) {
    if (table.getItemCount() <= 1) return;

    TableItem[] items = table.getItems();
    String[][] data = new String[items.length][table.getColumnCount()];
    for (int i = 0; i < items.length; i++) {
      for (int j = 0; j < table.getColumnCount(); j++) {
        data[i][j] = items[i].getText(j);
      }
    }

    Arrays.sort(data, new RowComparator(column));

    if (lastSortColumn != column) {
      table.setSortColumn(table.getColumn(column));
      table.setSortDirection(SWT.DOWN);
      for (int i = 0; i < data.length; i++) {
        items[i].setText(data[i]);
      }
      lastSortColumn = column;
    } else {
      // reverse order if the current column is selected again
      table.setSortDirection(SWT.UP);
      int j = data.length - 1;
      for (int i = 0; i < data.length; i++) {
        items[i].setText(data[j--]);
      }
      lastSortColumn = -1;
    }
  }
  private void sort(int column) {
    if (table.getItemCount() <= 1) return;

    TableItem[] items = table.getItems();
    String[][] data = new String[items.length][table.getColumnCount()];
    for (int i = 0; i < items.length; i++) {
      for (int j = 0; j < table.getColumnCount(); j++) {
        data[i][j] = items[i].getText(j);
      }
    }

    Arrays.sort(data, new RowComparator(column));

    for (int i = 0; i < data.length; i++) {
      items[i].setText(data[i]);
    }
  }
  private boolean save() {
    if (file == null) return saveAs();

    Cursor waitCursor = new Cursor(shell.getDisplay(), SWT.CURSOR_WAIT);
    shell.setCursor(waitCursor);

    TableItem[] items = table.getItems();
    String[] lines = new String[items.length];
    for (int i = 0; i < items.length; i++) {
      String[] itemText = new String[table.getColumnCount()];
      for (int j = 0; j < itemText.length; j++) {
        itemText[j] = items[i].getText(j);
      }
      lines[i] = encodeLine(itemText);
    }

    FileWriter fileWriter = null;
    try {
      fileWriter = new FileWriter(file.getAbsolutePath(), false);
      for (int i = 0; i < lines.length; i++) {
        fileWriter.write(lines[i]);
      }
    } catch (FileNotFoundException e) {
      displayError(resMessages.getString("File_not_found") + "\n" + file.getName());
      return false;
    } catch (IOException e) {
      displayError(resMessages.getString("IO_error_write") + "\n" + file.getName());
      return false;
    } finally {
      shell.setCursor(null);
      waitCursor.dispose();

      if (fileWriter != null) {
        try {
          fileWriter.close();
        } catch (IOException e) {
          displayError(resMessages.getString("IO_error_close") + "\n" + file.getName());
          return false;
        }
      }
    }

    shell.setText(resMessages.getString("Title_bar") + file.getName());
    isModified = false;
    return true;
  }
  private boolean closeAddressBook() {
    if (isModified) {
      // ask user if they want to save current address book
      MessageBox box = new MessageBox(shell, SWT.ICON_WARNING | SWT.YES | SWT.NO | SWT.CANCEL);
      box.setText(shell.getText());
      box.setMessage(resAddressBook.getString("Close_save"));

      int choice = box.open();
      if (choice == SWT.CANCEL) {
        return false;
      } else if (choice == SWT.YES) {
        if (!save()) return false;
      }
    }

    TableItem[] items = table.getItems();
    for (int i = 0; i < items.length; i++) {
      items[i].dispose();
    }

    return true;
  }