001    /* DefaultTableCellRenderer.java --
002       Copyright (C) 2002, 2004, 2005, 2006,  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package javax.swing.table;
040    
041    import java.awt.Color;
042    import java.awt.Component;
043    import java.awt.Rectangle;
044    import java.io.Serializable;
045    
046    import javax.swing.JLabel;
047    import javax.swing.JTable;
048    import javax.swing.UIManager;
049    import javax.swing.border.Border;
050    import javax.swing.border.EmptyBorder;
051    
052    /**
053     * Class to display every cells.
054     */
055    public class DefaultTableCellRenderer extends JLabel
056      implements TableCellRenderer, Serializable
057    {
058      static final long serialVersionUID = 7878911414715528324L;
059    
060      protected static Border noFocusBorder = new EmptyBorder(1, 1, 1, 1);
061    
062      public static class UIResource extends DefaultTableCellRenderer
063        implements javax.swing.plaf.UIResource
064      {
065        public UIResource()
066        {
067          super();
068        }
069      }
070    
071      /**
072       * Stores the color set by setForeground().
073       */
074      Color foreground;
075    
076      /**
077       * Stores the color set by setBackground().
078       */
079      Color background;
080    
081      /**
082       * Creates a default table cell renderer with an empty border.
083       */
084      public DefaultTableCellRenderer()
085      {
086        super();
087      }
088    
089      /**
090       * Assign the unselected-foreground.
091       *
092       * @param c the color to assign
093       */
094      public void setForeground(Color c)
095      {
096        super.setForeground(c);
097        foreground = c;
098      }
099    
100      /**
101       * Assign the unselected-background.
102       *
103       * @param c the color to assign
104       */
105      public void setBackground(Color c)
106      {
107        super.setBackground(c);
108        background = c;
109      }
110    
111      /**
112       * Look and feel has changed.
113       *
114       * <p>Replaces the current UI object with the  latest version from
115       * the UIManager.</p>
116       */
117      public void updateUI()
118      {
119        super.updateUI();
120        background = null;
121        foreground = null;
122      }
123    
124      /**
125       * Get the string value of the object and pass it to setText().
126       *
127       * @param table the JTable
128       * @param value the value of the object. For the text content,
129       *        null is rendered as an empty cell.
130       * @param isSelected is the cell selected?
131       * @param hasFocus has the cell the focus?
132       * @param row the row to render
133       * @param column the cell to render
134       * 
135       * @return this component (the default table cell renderer)
136       */
137      public Component getTableCellRendererComponent(JTable table, Object value,
138                                                     boolean isSelected,
139                                                     boolean hasFocus,
140                                                     int row, int column)
141      {
142        setValue(value);
143        setOpaque(true);
144    
145        if (table == null)
146          return this;
147    
148        if (isSelected)
149          {
150            super.setBackground(table.getSelectionBackground());
151            super.setForeground(table.getSelectionForeground());
152          }
153        else
154          {
155            if (background != null)
156              super.setBackground(background);
157            else
158              super.setBackground(table.getBackground());
159            if (foreground != null)
160              super.setForeground(foreground);
161            else
162              super.setForeground(table.getForeground());
163          }
164    
165        Border b = null;
166        if (hasFocus)
167          {
168            if (isSelected)
169              b = UIManager.getBorder("Table.focusSelectedCellHighlightBorder");
170            if (b == null)
171              b = UIManager.getBorder("Table.focusCellHighlightBorder");
172          }
173        else
174          b = noFocusBorder;
175        setBorder(b);
176    
177        setFont(table.getFont());
178    
179        // If the current background is equal to the table's background, then we
180        // can avoid filling the background by setting the renderer opaque.
181        Color back = getBackground();
182        setOpaque(back != null && back.equals(table.getBackground()));
183        
184        return this;    
185      }
186    
187      /**
188       * Overriden for performance.
189       *
190       * <p>This method needs to be overridden in a subclass to actually
191       * do something.</p>
192       *
193       * @return always true
194       */
195      public boolean isOpaque()
196      {
197        return true;
198      }
199    
200      /**
201       * Overriden for performance.
202       *
203       * <p>This method needs to be overridden in a subclass to actually
204       * do something.</p>
205       */
206      public void validate()
207      {
208        // Does nothing.
209      }
210    
211      public void revalidate()
212      {
213        // Does nothing.
214      }
215    
216      /**
217       * Overriden for performance.
218       *
219       * <p>This method needs to be overridden in a subclass to actually
220       * do something.</p>
221       */
222      public void repaint(long tm, int x, int y, int width, int height)
223      {
224        // Does nothing.
225      }
226    
227      /**
228       * Overriden for performance.
229       *
230       * <p>This method needs to be overridden in a subclass to actually
231       * do something.</p>
232       */
233      public void repaint(Rectangle r)
234      {
235        // Does nothing.
236      }
237    
238      /**
239       * Overriden for performance.
240       *
241       * <p>This method needs to be overridden in a subclass to actually
242       * do something.</p>
243       */
244      protected void firePropertyChange(String propertyName, Object oldValue,
245                                        Object newValue)
246      {
247        // Does nothing.
248      }
249    
250      /**
251       * Overriden for performance.
252       *
253       * <p>This method needs to be overridden in a subclass to actually
254       * do something.</p>
255       */
256      public void firePropertyChange(String propertyName, boolean oldValue,
257                                     boolean newValue)
258      {
259        // Does nothing.
260      }
261    
262      /**
263       * Sets the String for this cell.
264       * 
265       * @param value the string value for this cell; if value is null it
266       * sets the text value to an empty string
267       */
268      protected void setValue(Object value)
269      {
270        if (value != null)
271          setText(value.toString());
272        else
273          // null is rendered as an empty cell.
274          setText("");
275      }
276    }