java3d Picking objects
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I am building a java3d GUI, using which users can create custom scene graphs, without needing to know the code, i want to pick specific boxes using mouse, and i want to be able to move them around.. so for that i need picking.. 

There are say, 2 boxes and 2 spheres in my scenegraph. I just want to pick one of them and know which one was picked. I can find out what type of object was clicked, like if i click on specific sphere, or box, i can find that out, but i dont know how can i find out which object was it, so i can process it.   

Could anyone suggest me a solution to the problem? All I want is to know
which object was picked. That's all. 