solution for practice it

//http://practiceit.cs.washington.edu/problem.jsp?category=Building+Java+Programs%2C+3rd+edition%2FBJP3+Chapter+18&problem=bjp3-18-e9-kthSmallest
public int kthSmallest(PriorityQueue<Integer> queue, int k) throws IllegalArgumentException {
    if (k < 1 || k > queue.size()) {
        throw new IllegalArgumentException("k:" + k + " to small or to large for queueSize:" + queue.size());
    }
    Queue<Integer> buffer = new PriorityQueue<Integer>();
    buffer.addAll(queue);
    int kth = 0;
    final int size = buffer.size();
    for (int i = 0; i < size; i++) {
        if(i < k) {
            kth = buffer.peek();
        }
        buffer.poll();
    }
    return kth;
}