Jsplitapne, Jpanel clearing Not working

Question

I have one JSplitpane, on both left and right component of the same, I have added JPanel each i.e. on leftPanel and rightPanel.

On the leftPanel, I have added a Jtree, and on selection of leaf of that tree, I want to relatively paint the contents on rightPanel. This is not working, how do I achieve it ?

I am new to swings and don't know how do we clear all the component mounted on controller, in my case rightPanel.

here is what i have written in the jTree event listener..

tree.addTreeSelectionListener(new SelectionListener(){
              @Override
              public void valueChanged(TreeSelectionEvent se) {
                    JTree tree = (JTree) se.getSource();
                    DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
                    String selectedNodeName = selectedNode.toString();
                    if (selectedNode.isLeaf()) {
                        if(selectedNodeName.equals("Gold")){
                            rightpanel.repaint();
                            System.out.println(selectedNodeName);

                        }                   
                    }
                  }
          });

Kindly please provide suggestions.