HashMap-红黑树转链源码

final Node<K,V> untreeify(HashMap<K,V> map) {
    Node<K,V> hd = null, tl = null;
    // 遍历TreeNode
    for (Node<K,V> q = this; q != null; q = q.next) {
        // TreeNode替换Node
        Node<K,V> p = map.replacementNode(q, null);
        if (tl == null)
            hd = p;
        else
            tl.next = p;
        tl = p;
    }
    return hd;
}

// 替换方法
Node<K,V> replacementNode(Node<K,V> p, Node<K,V> next) {
    return new Node<>(p.hash, p.key, p.value, next);
}