private Node putImpl()

in spectator-reg-atlas/src/main/java/com/netflix/spectator/atlas/impl/PrefixTree.java [116:153]
33 lines of code
10 McCabe index (conditional complexity)

  private Node putImpl(Node node, String key, int offset, Query.KeyQuery value) {
    final int prefixLength = node.prefix.length();
    final int keyLength = key.length() - offset;
    final int commonLength = commonPrefixLength(node.prefix, key, offset);
    if (commonLength == 0 && prefixLength > 0) {
      // No common prefix
      Node n = addQuery(new Node(key.substring(offset), EMPTY), value);
      return new Node("", new Node[] {n, node});
    } else if (keyLength == prefixLength && commonLength == prefixLength) {
      // Fully matches, add the value to this node
      addQuery(node, value);
      return node;
    } else if (keyLength > prefixLength && commonLength == prefixLength) {
      // key.startsWith(prefix), put the value into a child
      int childOffset = offset + commonLength;
      int pos = find(node.children, key, childOffset);
      if (pos >= 0) {
        Node n = putImpl(node.children[pos], key, childOffset, value);
        return node.replaceChild(n, pos);
      } else {
        Node n = addQuery(new Node(key.substring(childOffset), EMPTY), value);
        return node.addChild(n);
      }
    } else if (prefixLength > keyLength && commonLength == keyLength) {
      // prefix.startsWith(key), make new parent node and add this node as a child
      int childOffset = offset + commonLength;
      Node n = new Node(node.prefix.substring(commonLength), node.children, node.inQueries, node.otherQueries);
      return addQuery(new Node(key.substring(offset, childOffset), new Node[] {n}), value);
    } else {
      // Common prefix is a subset of both
      int childOffset = offset + commonLength;
      Node[] children = {
          new Node(node.prefix.substring(commonLength), node.children, node.inQueries, node.otherQueries),
          addQuery(new Node(key.substring(childOffset), EMPTY), value)
      };
      return new Node(node.prefix.substring(0, commonLength), children);
    }
  }