In reply to donald:
You have to check the size of the queue just before randomizing the queue as below,
seq obj = new;
if(obj.my_q.size() != 0)
begin
if(obj.randomize() == 1)
$display("Randomizing is done");
//Do Something with the Queue here
else
$display("Randomization failed");
end
else
$display("\n Didn't Randomize as my_q.size() is not equal to zero \n");]
Thanks,
Sravan K