In JTree Not Able To Move Selection From One Node To Other

Hi Friends,
How are you all ? I am working with JTree and I am programatically
setting the first node in the tree selected and it is selected but my
problem is that I cannot move to other nodes directly if I want to do
it I first need to select the node again with the help of mouse and
after doing it I can move from one node to other using arrow keys.

Any Suggestions ?
Thanx

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