Echo Web Framework

Hi,
i want to be able to show a tooltip when an user hovering a node with the mouse,
i have extended the DefaultTreCellRenderer class but this method is never called
Note: my user object is not a Component
any suggestion?

thx

@Override
public Component getTreeCellRendererComponent(Tree tree, Object value, boolean selected, boolean expanded,
boolean leaf) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
SigmaNodeInfo nodeInfo = (SigmaNodeInfo) node.getUserObject();
Label label = (Label) componentMap.get(node);
if (label == null) {
label = new Label(nodeInfo.toString());
componentMap.put(node, label);
}
if (selected) {
label.setBackground(COLOR_SELECTED);
} else if (nodeInfo.getState().getName().equals("temporary")) {
label.setBackground(COLOR_TEMPORARY_STATE);
} else {
label.setBackground(COLOR_DEFAULT);
}
StringBuilder toolTipBuilder = new StringBuilder();
toolTipBuilder.append(nodeInfo.getNetworkNode().getDescription());
// ...
label.setToolTipText(toolTipBuilder.toString());
return label;
}