week05 作业

public class Hash {
    private static final int MAX_HASH = Integer.MAX_VALUE;
    private static final int VIRTUAL_SIZE = 100;
    private static final long VIRTUAL_NODE_DISTANCE = MAX_HASH / VIRTUAL_SIZE;
    private SortedMap<Integer, Node> map = new TreeMap<>();
    public void addNode(Node node) {
        int code = node.hashCode();
        for (int i = 0; i < VIRTUAL_SIZE; i++) {
            map.put((int)(code + i * VIRTUAL_NODE_DISTANCE) % MAX_HASH, node);
        }
    }
    public Node get(String key) {
        Integer code = key.hashCode();
        SortedMap<Integer, Node> tailMap = map.tailMap(code);
        if (tailMap.isEmpty()) {
            return map.get(map.firstKey());
        }
        return map.get(tailMap.firstKey());
    }
    static class Node {
        private String name;
        public Node(String name) {
            this.name = name;
        }
    }
    public static void main(String[] args) {
        Hash hash = new Hash();
        for (int i = 0; i < 10; i++) {
            Node node = new Node(String.valueOf(i));
            hash.addNode(node);
        }
    }
}