taxeditor-store/src/main/java/eu/etaxonomy/taxeditor/model/TextHelper.java

   1 // $Id$
   2 /**
   3 * Copyright (C) 2007 EDIT
   4 * European Distributed Institute of Taxonomy
   5 * http://www.e-taxonomy.eu
   6 *
   7 * The contents of this file are subject to the Mozilla Public License Version 1.1
   8 * See LICENSE.TXT at the top of this package for the full license terms.
   9 */
  10
  11 package eu.etaxonomy.taxeditor.model;
  12
  13 import org.eclipse.swt.graphics.GC;
  14 import org.eclipse.swt.widgets.Control;
  15
  16 /**
  17  * <p>TextHelper class.</p>
  18  *
  19  * @author n.hoffmann
  20  * @created Mar 30, 2010
  21  * @version 1.0
  22  */
  23 public class TextHelper {
  24
  25         /** Constant <code>ELLIPSIS="..."</code> */
  26         public static final String ELLIPSIS = "...";
  27
  28         /**
  29          * <p>shortenText</p>
  30          *
  31          * @param textValue a {@link java.lang.String} object.
  32          * @param control a {@link org.eclipse.swt.widgets.Control} object.
  33          * @see org.eclipse.jface.dialogs.Dialog#shortenText(String, Control)
  34          * @return a {@link java.lang.String} object.
  35          */
  36         public static String shortenText(String textValue, Control control) {
  37                 if (textValue == null) {
  38                         return null;
  39                 }
  40                 GC gc = new GC(control);
  41                 int maxWidth = control.getBounds().width;
  42                 int maxExtent = gc.textExtent(textValue).x;
  43                 if (maxExtent < maxWidth) {
  44                         gc.dispose();
  45                         return textValue;
  46                 }
  47                 int length = textValue.length();
  48                 int charsToClip = Math.round(0.95f*length * (1 - ((float)maxWidth/maxExtent)));
  49
  50                 int end = length - charsToClip;
  51                 while (end > 0) {
  52                         String s1 = textValue.substring(0, end);
  53                         String s = s1 + ELLIPSIS;
  54                         int l = gc.textExtent(s).x;
  55                         if (l < maxWidth) {
  56                                 gc.dispose();
  57                                 return s;
  58                         }
  59                         end--;
  60                 }
  61                 gc.dispose();
  62                 return textValue;
  63
  64         }
  65 }