tim/prune/load/TextFileLoader.java

   1 package tim.prune.load;
   2
   3 import java.awt.BorderLayout;
   4 import java.awt.CardLayout;
   5 import java.awt.Component;
   6 import java.awt.Dimension;
   7 import java.awt.FlowLayout;
   8 import java.awt.GridLayout;
   9 import java.awt.event.ActionEvent;
  10 import java.awt.event.ActionListener;
  11 import javax.swing.*;
  12 import javax.swing.event.DocumentEvent;
  13 import javax.swing.event.DocumentListener;
  14 import javax.swing.event.ListSelectionEvent;
  15 import javax.swing.event.ListSelectionListener;
  16 import javax.swing.table.TableCellEditor;
  17
  18 import java.io.File;
  19
  20 import tim.prune.App;
  21 import tim.prune.I18nManager;
  22 import tim.prune.data.Altitude;
  23 import tim.prune.data.Field;
  24
  25
  26 /**
  27  * Class to handle loading of text files including GUI options,
  28  * and passing loaded data back to App object
  29  */
  30 public class TextFileLoader
  31 {
  32         private File _file = null;
  33         private App _app = null;
  34         private JFrame _parentFrame = null;
  35         private JDialog _dialog = null;
  36         private JPanel _cardPanel = null;
  37         private CardLayout _layout = null;
  38         private JButton _backButton = null, _nextButton = null;
  39         private JButton _finishButton = null;
  40         private JButton _moveUpButton = null, _moveDownButton = null;
  41         private JRadioButton[] _delimiterRadios = null;
  42         private JTextField _otherDelimiterText = null;
  43         private JLabel _statusLabel = null;
  44         private DelimiterInfo[] _delimiterInfos = null;
  45         private FileCacher _fileCacher = null;
  46         private JList _snippetBox = null;
  47         private FileExtractTableModel _fileExtractTableModel = null;
  48         private JTable _fieldTable;
  49         private FieldSelectionTableModel _fieldTableModel = null;
  50         private JComboBox _unitsDropDown = null;
  51         private int _selectedField = -1;
  52         private char _currentDelimiter = ',';
  53
  54         // previously selected values
  55         private char _lastUsedDelimiter = ',';
  56         private Field[] _lastSelectedFields = null;
  57         private Altitude.Format _lastAltitudeFormat = Altitude.Format.NO_FORMAT;
  58
  59         // constants
  60         private static final int SNIPPET_SIZE = 6;
  61         private static final int MAX_SNIPPET_WIDTH = 80;
  62         private static final char[] DELIMITERS = {',', '\t', ';', ' '};
  63
  64
  65         /**
  66          * Inner class to listen for delimiter change operations
  67          */
  68         private class DelimListener implements ActionListener, DocumentListener
  69         {
  70                 public void actionPerformed(ActionEvent e)
  71                 {
  72                         informDelimiterSelected();
  73                 }
  74                 public void changedUpdate(DocumentEvent e)
  75                 {
  76                         informDelimiterSelected();
  77                 }
  78                 public void insertUpdate(DocumentEvent e)
  79                 {
  80                         informDelimiterSelected();
  81                 }
  82                 public void removeUpdate(DocumentEvent e)
  83                 {
  84                         informDelimiterSelected();
  85                 }
  86         }
  87
  88
  89         /**
  90          * Constructor
  91          * @param inApp Application object to inform of track load
  92          * @param inParentFrame parent frame to reference for dialogs
  93          */
  94         public TextFileLoader(App inApp, JFrame inParentFrame)
  95         {
  96                 _app = inApp;
  97                 _parentFrame = inParentFrame;
  98         }
  99
 100
 101         /**
 102          * Open the selected file and show the GUI dialog to select load options
 103          * @param inFile file to open
 104          */
 105         public void openFile(File inFile)
 106         {
 107                 _file = inFile;
 108                 if (preCheckFile(_file))
 109                 {
 110                         _dialog = new JDialog(_parentFrame, I18nManager.getText("dialog.openoptions.title"), true);
 111                         _dialog.setLocationRelativeTo(_parentFrame);
 112                         _dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
 113                         _dialog.getContentPane().add(makeDialogComponents());
 114
 115                         // select best separator according to row counts (more is better)
 116                         int bestDelim = getBestOption(_delimiterInfos[0].getNumWinningRecords(),
 117                                 _delimiterInfos[1].getNumWinningRecords(), _delimiterInfos[2].getNumWinningRecords(),
 118                                 _delimiterInfos[3].getNumWinningRecords());
 119                         if (bestDelim >= 0)
 120                                 _delimiterRadios[bestDelim].setSelected(true);
 121                         else
 122                                 _delimiterRadios[_delimiterRadios.length-1].setSelected(true);
 123                         informDelimiterSelected();
 124                         _dialog.pack();
 125                         _dialog.setVisible(true);
 126                 }
 127                 else {
 128                         // Didn't pass pre-check
 129                         _app.showErrorMessage("error.load.dialogtitle", "error.load.noread");
 130                         _app.informNoDataLoaded();
 131                 }
 132         }
 133
 134
 135         /**
 136          * Check the given file for readability and funny characters,
 137          * and count the fields for the various separators
 138          * @param inFile file to check
 139          */
 140         private boolean preCheckFile(File inFile)
 141         {
 142                 // Check file exists and is readable
 143                 if (inFile == null || !inFile.exists() || !inFile.canRead())
 144                 {
 145                         return false;
 146                 }
 147                 // Use a FileCacher to read the file into an array
 148                 _fileCacher = new FileCacher(inFile);
 149
 150                 // Check each line of the file
 151                 String[] fileContents = _fileCacher.getContents();
 152                 boolean fileOK = true;
 153                 _delimiterInfos = new DelimiterInfo[5];
 154                 for (int i=0; i<4; i++) _delimiterInfos[i] = new DelimiterInfo(DELIMITERS[i]);
 155
 156                 String currLine = null;
 157                 String[] splitFields = null;
 158                 int commaFields = 0, semicolonFields = 0, tabFields = 0, spaceFields = 0;
 159                 for (int lineNum=0; lineNum<fileContents.length && fileOK; lineNum++)
 160                 {
 161                         currLine = fileContents[lineNum];
 162                         // check for invalid characters
 163                         if (currLine.indexOf('\0') >= 0) {fileOK = false;}
 164                         // check for commas
 165                         splitFields = currLine.split(",");
 166                         commaFields = splitFields.length;
 167                         if (commaFields > 1) _delimiterInfos[0].incrementNumRecords();
 168                         _delimiterInfos[0].updateMaxFields(commaFields);
 169                         // check for tabs
 170                         splitFields = currLine.split("\t");
 171                         tabFields = splitFields.length;
 172                         if (tabFields > 1) _delimiterInfos[1].incrementNumRecords();
 173                         _delimiterInfos[1].updateMaxFields(tabFields);
 174                         // check for semicolons
 175                         splitFields = currLine.split(";");
 176                         semicolonFields = splitFields.length;
 177                         if (semicolonFields > 1) _delimiterInfos[2].incrementNumRecords();
 178                         _delimiterInfos[2].updateMaxFields(semicolonFields);
 179                         // check for spaces
 180                         splitFields = currLine.split(" ");
 181                         spaceFields = splitFields.length;
 182                         if (spaceFields > 1) _delimiterInfos[3].incrementNumRecords();
 183                         _delimiterInfos[3].updateMaxFields(spaceFields);
 184                         // increment counters
 185                         int bestScorer = getBestOption(commaFields, tabFields, semicolonFields, spaceFields);
 186                         if (bestScorer >= 0)
 187                                 _delimiterInfos[bestScorer].incrementNumWinningRecords();
 188                 }
 189                 return fileOK;
 190         }
 191
 192
 193         /**
 194          * Get the index of the best one in the list
 195          * @return the index of the maximum of the four given values
 196          */
 197         private static int getBestOption(int inOpt0, int inOpt1, int inOpt2, int inOpt3)
 198         {
 199                 int bestIndex = -1;
 200                 int maxScore = 1;
 201                 if (inOpt0 > maxScore) {bestIndex = 0; maxScore = inOpt0;}
 202                 if (inOpt1 > maxScore) {bestIndex = 1; maxScore = inOpt1;}
 203                 if (inOpt2 > maxScore) {bestIndex = 2; maxScore = inOpt2;}
 204                 if (inOpt3 > maxScore) {bestIndex = 3; maxScore = inOpt3;}
 205                 return bestIndex;
 206         }
 207
 208
 209         /**
 210          * Make the components for the open options dialog
 211          * @return Component for all options
 212          */
 213         private Component makeDialogComponents()
 214         {
 215                 JPanel wholePanel = new JPanel();
 216                 wholePanel.setLayout(new BorderLayout());
 217
 218                 // add buttons to south
 219                 JPanel buttonPanel = new JPanel();
 220                 buttonPanel.setLayout(new FlowLayout(FlowLayout.CENTER));
 221                 _backButton = new JButton(I18nManager.getText("button.back"));
 222                 _backButton.addActionListener(new ActionListener() {
 223                         public void actionPerformed(ActionEvent e)
 224                         {
 225                                 _layout.previous(_cardPanel);
 226                                 _backButton.setEnabled(false);
 227                                 _nextButton.setEnabled(true);
 228                                 _finishButton.setEnabled(false);
 229                         }
 230                 });
 231                 _backButton.setEnabled(false);
 232                 buttonPanel.add(_backButton);
 233                 _nextButton = new JButton(I18nManager.getText("button.next"));
 234                 _nextButton.addActionListener(new ActionListener() {
 235                         public void actionPerformed(ActionEvent e)
 236                         {
 237                                 prepareSecondPanel();
 238                                 _layout.next(_cardPanel);
 239                                 _nextButton.setEnabled(false);
 240                                 _backButton.setEnabled(true);
 241                                 _finishButton.setEnabled(_fieldTableModel.getRowCount() > 1);
 242                         }
 243                 });
 244                 buttonPanel.add(_nextButton);
 245                 _finishButton = new JButton(I18nManager.getText("button.finish"));
 246                 _finishButton.addActionListener(new ActionListener() {
 247                         public void actionPerformed(ActionEvent e)
 248                         {
 249                                 finished();
 250                         }
 251                 });
 252                 _finishButton.setEnabled(false);
 253                 buttonPanel.add(_finishButton);
 254                 JButton cancelButton = new JButton(I18nManager.getText("button.cancel"));
 255                 cancelButton.addActionListener(new ActionListener() {
 256                         public void actionPerformed(ActionEvent e)
 257                         {
 258                                 _dialog.dispose();
 259                                 _app.informNoDataLoaded();
 260                         }
 261                 });
 262                 buttonPanel.add(cancelButton);
 263                 wholePanel.add(buttonPanel, BorderLayout.SOUTH);
 264
 265                 // Make the two cards, for delimiter and fields
 266                 _cardPanel = new JPanel();
 267                 _layout = new CardLayout();
 268                 _cardPanel.setLayout(_layout);
 269                 JPanel firstCard = new JPanel();
 270                 firstCard.setLayout(new BorderLayout());
 271                 firstCard.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 15));
 272
 273                 JPanel delimsPanel = new JPanel();
 274                 delimsPanel.setLayout(new GridLayout(0, 2));
 275                 delimsPanel.add(new JLabel(I18nManager.getText("dialog.delimiter.label")));
 276                 delimsPanel.add(new JLabel("")); // blank label to go to next grid row
 277                 // radio buttons
 278                 _delimiterRadios = new JRadioButton[5];
 279                 _delimiterRadios[0] = new JRadioButton(I18nManager.getText("dialog.delimiter.comma"));
 280                 delimsPanel.add(_delimiterRadios[0]);
 281                 _delimiterRadios[1] = new JRadioButton(I18nManager.getText("dialog.delimiter.tab"));
 282                 delimsPanel.add(_delimiterRadios[1]);
 283                 _delimiterRadios[2] = new JRadioButton(I18nManager.getText("dialog.delimiter.semicolon"));
 284                 delimsPanel.add(_delimiterRadios[2]);
 285                 _delimiterRadios[3] = new JRadioButton(I18nManager.getText("dialog.delimiter.space"));
 286                 delimsPanel.add(_delimiterRadios[3]);
 287                 JPanel otherPanel = new JPanel();
 288                 otherPanel.setLayout(new FlowLayout(FlowLayout.LEFT, 0, 0));
 289                 _delimiterRadios[4] = new JRadioButton(I18nManager.getText("dialog.delimiter.other"));
 290                 otherPanel.add(_delimiterRadios[4]);
 291                 _otherDelimiterText = new JTextField(new OneCharDocument(), null, 2);
 292                 otherPanel.add(_otherDelimiterText);
 293                 // Group radio buttons
 294                 ButtonGroup delimGroup = new ButtonGroup();
 295                 DelimListener delimListener = new DelimListener();
 296                 for (int i=0; i<_delimiterRadios.length; i++)
 297                 {
 298                         delimGroup.add(_delimiterRadios[i]);
 299                         _delimiterRadios[i].addActionListener(delimListener);
 300                 }
 301                 _otherDelimiterText.getDocument().addDocumentListener(delimListener);
 302                 delimsPanel.add(new JLabel(""));
 303                 delimsPanel.add(otherPanel);
 304                 _statusLabel = new JLabel("");
 305                 delimsPanel.add(_statusLabel);
 306                 firstCard.add(delimsPanel, BorderLayout.SOUTH);
 307                 // load snippet to show first few lines
 308                 _snippetBox = new JList(_fileCacher.getSnippet(SNIPPET_SIZE, MAX_SNIPPET_WIDTH));
 309                 _snippetBox.setEnabled(false);
 310                 firstCard.add(makeLabelledPanel("dialog.openoptions.filesnippet", _snippetBox), BorderLayout.CENTER);
 311
 312                 // Second screen, for field order selection
 313                 JPanel secondCard = new JPanel();
 314                 secondCard.setLayout(new BorderLayout());
 315                 secondCard.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 15));
 316                 // table for file contents
 317                 _fileExtractTableModel = new FileExtractTableModel();
 318                 JTable extractTable = new JTable(_fileExtractTableModel);
 319                 JScrollPane tableScrollPane = new JScrollPane(extractTable);
 320                 extractTable.setPreferredScrollableViewportSize(new Dimension(350, 80));
 321                 extractTable.getTableHeader().setReorderingAllowed(false);
 322                 secondCard.add(makeLabelledPanel("dialog.openoptions.filesnippet", tableScrollPane), BorderLayout.NORTH);
 323                 JPanel innerPanel2 = new JPanel();
 324                 innerPanel2.setLayout(new BorderLayout());
 325                 innerPanel2.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
 326
 327                 _fieldTable = new JTable(new FieldSelectionTableModel());
 328                 _fieldTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
 329                 // add listener for selected table row
 330                 _fieldTable.getSelectionModel().addListSelectionListener(
 331                         new ListSelectionListener() {
 332                                 public void valueChanged(ListSelectionEvent e) {
 333                                         ListSelectionModel lsm = (ListSelectionModel) e.getSource();
 334                                         if (lsm.isSelectionEmpty()) {
 335                                                 //no rows are selected
 336                                                 selectField(-1);
 337                                         } else {
 338                                                 selectField(lsm.getMinSelectionIndex());
 339                                         }
 340                                 }
 341                         });
 342                 JPanel tablePanel = new JPanel();
 343                 tablePanel.setLayout(new BorderLayout());
 344                 tablePanel.add(_fieldTable.getTableHeader(), BorderLayout.NORTH);
 345                 tablePanel.add(_fieldTable, BorderLayout.CENTER);
 346                 innerPanel2.add(tablePanel, BorderLayout.CENTER);
 347
 348                 JPanel innerPanel3 = new JPanel();
 349                 innerPanel3.setLayout(new BoxLayout(innerPanel3, BoxLayout.Y_AXIS));
 350                 _moveUpButton = new JButton(I18nManager.getText("button.moveup"));
 351                 _moveUpButton.addActionListener(new ActionListener() {
 352                         public void actionPerformed(ActionEvent e)
 353                         {
 354                                 int currRow = _fieldTable.getSelectedRow();
 355                                 closeTableComboBox(currRow);
 356                                 _fieldTableModel.moveUp(currRow);
 357                                 _fieldTable.setRowSelectionInterval(currRow-1, currRow-1);
 358                         }
 359                 });
 360                 innerPanel3.add(_moveUpButton);
 361                 _moveDownButton = new JButton(I18nManager.getText("button.movedown"));
 362                 _moveDownButton.addActionListener(new ActionListener() {
 363                         public void actionPerformed(ActionEvent e)
 364                         {
 365                                 int currRow = _fieldTable.getSelectedRow();
 366                                 closeTableComboBox(currRow);
 367                                 _fieldTableModel.moveDown(currRow);
 368                                 _fieldTable.setRowSelectionInterval(currRow+1, currRow+1);
 369                         }
 370                 });
 371                 innerPanel3.add(_moveDownButton);
 372                 innerPanel3.add(Box.createVerticalStrut(60));
 373                 JButton guessButton = new JButton(I18nManager.getText("button.guessfields"));
 374                 guessButton.addActionListener(new ActionListener() {
 375                         public void actionPerformed(ActionEvent e)
 376                         {
 377                                 _lastSelectedFields = null;
 378                                 prepareSecondPanel();
 379                         }
 380                 });
 381                 innerPanel3.add(guessButton);
 382
 383                 innerPanel2.add(innerPanel3, BorderLayout.EAST);
 384                 secondCard.add(innerPanel2, BorderLayout.CENTER);
 385                 JPanel altUnitsPanel = new JPanel();
 386                 altUnitsPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
 387                 altUnitsPanel.add(new JLabel(I18nManager.getText("dialog.openoptions.altitudeunits")));
 388                 String[] units = {I18nManager.getText("units.metres"), I18nManager.getText("units.feet")};
 389                 _unitsDropDown = new JComboBox(units);
 390                 altUnitsPanel.add(_unitsDropDown);
 391                 secondCard.add(altUnitsPanel, BorderLayout.SOUTH);
 392                 _cardPanel.add(firstCard, "card1");
 393                 _cardPanel.add(secondCard, "card2");
 394
 395                 wholePanel.add(_cardPanel, BorderLayout.CENTER);
 396                 return wholePanel;
 397         }
 398
 399
 400         /**
 401          * Close the combo box on the selected row of the field table
 402          * @param inRow currently selected row number
 403          */
 404         private void closeTableComboBox(int inRow)
 405         {
 406                 TableCellEditor editor = _fieldTable.getCellEditor(inRow, 1);
 407                 if (editor != null)
 408                 {
 409                         editor.stopCellEditing();
 410                 }
 411         }
 412
 413
 414         /**
 415          * change the status based on selection of a delimiter
 416          */
 417         protected void informDelimiterSelected()
 418         {
 419                 int fields = 0;
 420                 // Loop through radios to see which one is selected
 421                 for (int i=0; i<(_delimiterRadios.length-1); i++)
 422                 {
 423                         if (_delimiterRadios[i].isSelected())
 424                         {
 425                                 // Set label text to describe records and fields
 426                                 int numRecords = _delimiterInfos[i].getNumRecords();
 427                                 if (numRecords == 0)
 428                                 {
 429                                         _statusLabel.setText(I18nManager.getText("dialog.openoptions.deliminfo.norecords"));
 430                                 }
 431                                 else
 432                                 {
 433                                         fields = _delimiterInfos[i].getMaxFields();
 434                                         _statusLabel.setText("" + numRecords + " " + I18nManager.getText("dialog.openoptions.deliminfo.records")
 435                                                 + " " + fields + " " + I18nManager.getText("dialog.openoptions.deliminfo.fields"));
 436                                 }
 437                         }
 438                 }
 439                 // Don't show label if "other" delimiter is chosen (as records, fields are unknown)
 440                 if (_delimiterRadios[_delimiterRadios.length-1].isSelected())
 441                 {
 442                         _statusLabel.setText("");
 443                 }
 444                 // enable/disable next button
 445                 _nextButton.setEnabled((_delimiterRadios[4].isSelected() == false && fields > 1)
 446                         || _otherDelimiterText.getText().length() == 1);
 447         }
 448
 449
 450         /**
 451          * Get the delimiter info from the first step
 452          * @return delimiter information object for the selected delimiter
 453          */
 454         public DelimiterInfo getSelectedDelimiterInfo()
 455         {
 456                 for (int i=0; i<4; i++)
 457                         if (_delimiterRadios[i].isSelected()) return _delimiterInfos[i];
 458                 // must be "other" - build info if necessary
 459                 if (_delimiterInfos[4] == null)
 460                         _delimiterInfos[4] = new DelimiterInfo(_otherDelimiterText.getText().charAt(0));
 461                 return _delimiterInfos[4];
 462         }
 463
 464
 465         /**
 466          * Use the delimiter selected to determine the fields in the file
 467          * and prepare the second panel accordingly
 468          */
 469         private void prepareSecondPanel()
 470         {
 471                 DelimiterInfo info = getSelectedDelimiterInfo();
 472                 FileSplitter splitter = new FileSplitter(_fileCacher);
 473                 // Check info makes sense - num fields > 0, num records > 0
 474                 // set "Finished" button to disabled if not ok
 475                 // Add data to GUI elements
 476                 String[][] tableData = splitter.splitFieldData(info.getDelimiter());
 477                 // possible to ignore blank columns here
 478                 _currentDelimiter = info.getDelimiter();
 479                 _fileExtractTableModel.updateData(tableData);
 480                 _fieldTableModel = new FieldSelectionTableModel();
 481
 482                 // Check number of fields and use last ones if count matches
 483                 Field[] startFieldArray = null;
 484                 if (_lastSelectedFields != null && splitter.getNumColumns() == _lastSelectedFields.length)
 485                 {
 486                         startFieldArray = _lastSelectedFields;
 487                 }
 488                 else
 489                 {
 490                         // Take first full row of file and use it to guess fields
 491                         startFieldArray = FieldGuesser.guessFields(splitter.getFirstFullRow());
 492                 }
 493
 494                 _fieldTableModel.updateData(startFieldArray);
 495                 _fieldTable.setModel(_fieldTableModel);
 496                 // add dropdowns to second column
 497                 JComboBox fieldTypesBox = new JComboBox();
 498                 String[] fieldNames = Field.getFieldNames();
 499                 for (int i=0; i<fieldNames.length; i++)
 500                 {
 501                         fieldTypesBox.addItem(fieldNames[i]);
 502                 }
 503                 _fieldTable.getColumnModel().getColumn(1).setCellEditor(new DefaultCellEditor(fieldTypesBox));
 504
 505                 // Set altitude format to same as last time if available
 506                 if (_lastAltitudeFormat == Altitude.Format.METRES)
 507                         _unitsDropDown.setSelectedIndex(0);
 508                 else if (_lastAltitudeFormat == Altitude.Format.FEET)
 509                         _unitsDropDown.setSelectedIndex(1);
 510                 // no selection on field list
 511                 selectField(-1);
 512         }
 513
 514
 515         /**
 516          * All options have been selected, so load file
 517          */
 518         private void finished()
 519         {
 520                 // Save delimiter, field array and altitude format for later use
 521                 _lastUsedDelimiter = _currentDelimiter;
 522                 _lastSelectedFields = _fieldTableModel.getFieldArray();
 523                 Altitude.Format altitudeFormat = Altitude.Format.METRES;
 524                 if (_unitsDropDown.getSelectedIndex() == 1)
 525                 {
 526                         altitudeFormat = Altitude.Format.FEET;
 527                 }
 528                 _lastAltitudeFormat = altitudeFormat;
 529                 // give data to App
 530                 _app.informDataLoaded(_fieldTableModel.getFieldArray(),
 531                         _fileExtractTableModel.getData(), altitudeFormat,
 532                         _file.getName());
 533                 // clear up file cacher
 534                 _fileCacher.clear();
 535                 // dispose of dialog
 536                 _dialog.dispose();
 537         }
 538
 539
 540         /**
 541          * Make a panel with a label and a component
 542          * @param inLabelKey label key to use
 543          * @param inComponent component for main area of panel
 544          * @return labelled Panel
 545          */
 546         private static JPanel makeLabelledPanel(String inLabelKey, JComponent inComponent)
 547         {
 548                 JPanel panel = new JPanel();
 549                 panel.setLayout(new BorderLayout());
 550                 panel.add(new JLabel(I18nManager.getText(inLabelKey)), BorderLayout.NORTH);
 551                 panel.add(inComponent, BorderLayout.CENTER);
 552                 return panel;
 553         }
 554
 555
 556         /**
 557          * An entry in the field list has been selected
 558          * @param inFieldNum index of field, starting with 0
 559          */
 560         private void selectField(int inFieldNum)
 561         {
 562                 if (inFieldNum == -1 || inFieldNum != _selectedField)
 563                 {
 564                         _selectedField = inFieldNum;
 565                         _moveUpButton.setEnabled(inFieldNum > 0);
 566                         _moveDownButton.setEnabled(inFieldNum >= 0
 567                                 && inFieldNum < (_fieldTableModel.getRowCount()-1));
 568                 }
 569         }
 570
 571
 572         /**
 573          * @return the last delimiter character used for a load
 574          */
 575         public char getLastUsedDelimiter()
 576         {
 577                 return _lastUsedDelimiter;
 578         }
 579 }