Changing JTree Node Icon dynamically

Question

I have implemented a JTree using the DefaultTreeModel.I am storing Message type objects in the tree where I set the node icons initially according to a direction variable value of the Message. I can do this successfully using the below code.

    tcBuilderTree = new JTree(treeModel);
tcBuilderTree.getSelectionModel().setSelectionMode
(TreeSelectionModel.SINGLE_TREE_SELECTION);

tcBuilderTree.setCellRenderer(new DefaultTreeCellRenderer(){

        public Component getTreeCellRendererComponent(JTree tree,
                                                      Object value, 
                                                      boolean selected, 
                                                      boolean expanded,
                                                      boolean isLeaf, 
                                                      int row, 
                                                      boolean focused) {
            Component c = super.getTreeCellRendererComponent(tree, value,
                    selected, expanded, isLeaf, row, focused);

            if(value instanceof CustomMessageTreeNode){
                setIcon(((CustomMessageTreeNode)value).
                getMessage().getMessageDirectionIcon());
            }

            return c;
        }
    });


    //implementation of getMessageDirectionIcon()
    public ImageIcon getMessageDirectionIcon(){
        ImageIcon icon=null;
        URL messageIconUrl;

        if(msgDirection.equalsIgnoreCase("In")){
            messageIconUrl = ToolBar.class.getResource
            ("/icons/arrowRight.png");
            icon=new ImageIcon(messageIconUrl);
        }
        else if(msgDirection.equalsIgnoreCase("Out")){
            messageIconUrl = ToolBar.class.getResource
            ("/icons/arrowLeft.png");
            icon=new ImageIcon(messageIconUrl);
        }
        return icon;
    }

Dynamically I want to let the user select the node and change its direction so that the node icon gets changed. I'm doing it through the foloowing code.

    public void toggleDirection(){
    CustomMessageTreeNode currentSelectedNode = 
        (CustomMessageTreeNode) tcBuilderTree.getLastSelectedPathComponent();
    Message toggleMessage=currentSelectedNode.getMessage();

    tcBuilderTree.setCellRenderer(new DefaultTreeCellRenderer(){
        @Override
        public Component getTreeCellRendererComponent(JTree tree,
                                                      Object value, 
                                                      boolean selected, 
                                                      boolean expanded,
                                                      boolean isLeaf, 
                                                      int row, 
                                                      boolean focused) {
            Component c = super.getTreeCellRendererComponent(tree, value,
                    selected, expanded, isLeaf, row, focused);

            if(value instanceof CustomMessageTreeNode){
                String currentDirection=toggleMessage.getMsgDirection();

                if(currentDirection.equalsIgnoreCase("In")){
                    toggleMessage.setMsgDirection("Out");
                    System.out.println("Direction changed as : Out");
                    setIcon(toggleMessage.getMessageDirectionIcon());
                    return c;
                }
                if(currentDirection.equalsIgnoreCase("Out")){
                    toggleMessage.setMsgDirection("In");
                    System.out.println("Direction changed as : In");
                    setIcon(toggleMessage.getMessageDirectionIcon());
                    return c;

                }
            }
            return c;
        }
    });
}

This is my CustomMessageNode class.

public class CustomMessageTreeNode extends DefaultMutableTreeNode{
    private Message message;

    public CustomMessageTreeNode(String msgName){
        super(msgName);
    }   
    public Message getMessage() {
        return message;
    }    
    public void setMessage(Message message) {
        this.message = message;
    }   
}

Once I change the direction by selecting the node the icon gets changed. But the issue happens whenever I click on some other node or somewhere in my JFrame the icon keeps on changing the direction. I debugged and made sure that the toggleDirection() function is called only once when I click the node and said to change the direction.

Please let me know why this happens and is there a better way to do this.What is the reason for the node icon to keep on changing when the user changes it once.