how can we implement compare method of compartor class

how can we implement compare method of compartor class

how can we implement compare method based on employee Id?
public int compare(Employee emp1, Employee emp2) {
throw new UnsupportedOperationException("Not supported yet.");
if(emp1.getEmpid()<emp2.getEmpid())
{
return -1;
}
else if(emp1.getEmpid()>emp2.getEmpid())
return 1;
else
return 0;
}