eclipseprojects/eu.etaxonomy.taxeditor/src/eu/etaxonomy/taxeditor/editor/LineBreakListener.java

   1 /**
   2 * Copyright (C) 2007 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9
  10 package eu.etaxonomy.taxeditor.editor;
  11
  12 import java.util.Scanner;
  13
  14 import org.apache.log4j.Logger;
  15 import org.eclipse.swt.custom.StyledText;
  16 import org.eclipse.swt.events.VerifyEvent;
  17 import org.eclipse.swt.events.VerifyListener;
  18
  19 /**
  20  * Checks text entered into a StyledText widget for line breaks, sends
  21  *  split text to abstract method handleSplitText().
  22  *
  23  * @author p.ciardelli
  24  * @created 19.05.2008
  25  * @version 1.0
  26  */
  27 public abstract class LineBreakListener implements VerifyListener {
  28         private static final Logger logger = Logger
  29                         .getLogger(LineBreakListener.class);
  30
  31         /**
  32          * Checks for 3 conditions of name viewer text:
  33          *   1) no line breaks in text
  34          *   2) line break at the end of the text
  35          *   3) line break in the middle of the text
  36          *
  37          * @see org.eclipse.swt.events.VerifyListener#verifyText(org.eclipse.swt.events.VerifyEvent)
  38          */
  39         public void verifyText(VerifyEvent e) {
  40
  41                 String verifyText = e.text;
  42
  43                 StyledText styledText = (StyledText) e.widget;
  44                 String widgetText = styledText.getText();
  45                 int cursorPosition = styledText.getCaretOffset();
  46
  47                 // If no line break in verifyText, Parse text normally
  48                 if (!verifyText.contains(System.getProperty("line.separator"))) {
  49                         return;
  50                 }
  51
  52                 // Don't add verifyText without further processing
  53                 e.doit = false;
  54
  55                 // If user has entered return at the end of the line,
  56                 //  make a new, empty synonym
  57                 if (widgetText.length() == cursorPosition &&
  58                                 verifyText.equals(System.getProperty("line.separator"))) {
  59                         handleSplitText("");
  60                         return;
  61                 }
  62
  63                 // Concatenate old and new texts
  64                 String textForSplitting = widgetText.substring(0, cursorPosition)
  65                                 + verifyText
  66                                 + widgetText.substring(cursorPosition);
  67
  68                 // Split on line breaks
  69                 Scanner scanner = new Scanner( textForSplitting );
  70                 scanner.useDelimiter (System.getProperty("line.separator"));
  71
  72                 // Put first string into name viewer
  73                 styledText.setText(scanner.next());
  74
  75                 // Start new synonyms with the rest
  76                 while (scanner.hasNext()) {
  77                         handleSplitText(scanner.next());
  78                 }
  79         }
  80
  81         abstract public void handleSplitText(String text);
  82 }