Best books about JAVA programming:

• Head First JAVA, Second Editon
• Effective Java Programming Language Guide
• Professional Java, JDK 5 Edition
• Ivor Horton's Beginning Java 2, JDK 5 Edition

JAVA JTree Icon node

The following code adds icons on JTree node. Each node could have different icon. This example has four files: IconNodeTreeExample.java,IconNodeRenderer.java,IconNode.java and TextIcons.java

/*Example modified from http://www.crionics.com/products/opensource/faq/swing_ex/JTableExamples2.html
*/

import java.util.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.tree.*;

public class IconNodeRenderer extends DefaultTreeCellRenderer {

public Component getTreeCellRendererComponent(JTree tree, Object value,
boolean sel, boolean expanded, boolean leaf,
int row, boolean hasFocus) {

super.getTreeCellRendererComponent(tree, value,
sel, expanded, leaf, row, hasFocus);

Icon icon = ((IconNode)value).getIcon();

if (icon == null) {
Hashtable icons = (Hashtable)tree.getClientProperty("JTree.icons");
String name = ((IconNode)value).getIconName();
if ((icons != null) && (name != null)) {
icon = (Icon)icons.get(name);
if (icon != null) {
setIcon(icon);
}
}
} else {
setIcon(icon);
}

return this;
}
}