Java数据结构-HashMap详解

static <K,V> TreeNode<K,V> rotateLeft(TreeNode<K,V> root,
                       TreeNode<K,V> p) {
      TreeNode<K,V> r, pp, rl;
      if (p != null && (r = p.right) != null) {
        if ((rl = p.right = r.left) != null)
          rl.parent = p;
        if ((pp = r.parent = p.parent) == null)
          (root = r).red = false;
        else if (pp.left == p)
          pp.left = r;
        else
          pp.right = r;
        r.left = p;
        p.parent = r;
      }
      return root;
    }

static <K,V> TreeNode<K,V> rotateRight(TreeNode<K,V> root,
                        TreeNode<K,V> p) {
      TreeNode<K,V> l, pp, lr;
      if (p != null && (l = p.left) != null) {
        if ((lr = p.left = l.right) != null)
          lr.parent = p;
        if ((pp = l.parent = p.parent) == null)
          (root = l).red = false;
        else if (pp.right == p)
          pp.right = l;
        else
          pp.left = l;
        l.right = p;
        p.parent = l;
      }
      return root;
    }

static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root,
                          TreeNode<K,V> x) {
      x.red = true;
      for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
        if ((xp = x.parent) == null) {
          x.red = false;
          return x;
        }
        else if (!xp.red || (xpp = xp.parent) == null) //①
          return root;
        if (xp == (xppl = xpp.left)) {
          if ((xppr = xpp.right) != null && xppr.red) { //②
            xppr.red = false;
            xp.red = false;
            xpp.red = true;
            x = xpp;
          }
          else {
            if (x == xp.right) { //③
              root = rotateLeft(root, x = xp);
              xpp = (xp = x.parent) == null ? null : xp.parent;
            }
            if (xp != null) { //④
              xp.red = false;
              if (xpp != null) {
                xpp.red = true;
                root = rotateRight(root, xpp);
              }
            }
          }
        }
        else {
          if (xppl != null && xppl.red) { //②
            xppl.red = false;
            xp.red = false;
            xpp.red = true;
            x = xpp;
          }
          else {
            if (x == xp.left) {    //⑤
              root = rotateRight(root, x = xp);
              xpp = (xp = x.parent) == null ? null : xp.parent;
            }
            if (xp != null) {  //⑥
              xp.red = false;
              if (xpp != null) {
                xpp.red = true;
                root = rotateLeft(root, xpp);
              }
            }
          }
        }
      }
    }