Problems with Drag and Drop

[Rudra Kumar]

Hi All,
I am writing an app where I am using Drag & Drop.
When I am dragging a tree node, the path is shown like this.
"Dragging from tree path = [Data, Geographic, US States]"
"Parent path = USA"
When I drop the tree node on some other node, this is happening.
"Removing the tree node"
"Dropping from tree path = [null, null, null]"
When I am drop the node, the node is removed from the original place.
But the Drop tree path is showing null. So, my tree node at the new
path is created as null DefaultMutableTreeNodes with no information in them.
Both the Drag & Drop tree path should have been the same for proper functioning of the program.
What can probably cause this problem?
Thanks in Advance,
Rudra