private static void insert()

in hpack/src/main/java/com/twitter/hpack/HuffmanDecoder.java [135:157]

• 21 lines of code
• 5 McCabe index (conditional complexity)

  private static void insert(Node root, int symbol, int code, byte length) {
    // traverse tree using the most significant bytes of code
    Node current = root;
    while (length > 8) {
      if (current.isTerminal()) {
        throw new IllegalStateException("invalid Huffman code: prefix not unique");
      }
      length -= 8;
      int i = (code >>> length) & 0xFF;
      if (current.children[i] == null) {
        current.children[i] = new Node();
      }
      current = current.children[i];
    }

    Node terminal = new Node(symbol, length);
    int shift = 8 - length;
    int start = (code << shift) & 0xFF;
    int end = 1 << shift;
    for (int i = start; i < start + end; i++) {
      current.children[i] = terminal;
    }
  }