you can do setPiority. That is o.k. but , the o.s is having their priorities. Thus , it is totally O.S. Dependent.
Java's threading model has got 10 priorities. if o.s. has got 5 prorities. then 2 priorities of java threading model will mapped to one priority of o.s. so , behavoiur of setPriority() can not be gauranteed. for NT , you have diff. priority levels , solaris , you have diff. priority levels.
Correct me if I am wrong.
more infomation about this you can get in " Threading " Discussion Forum.