docs: protected void insertLeafEntry(E entry) {
      lastInsertedEntry = entry;
      // choose subtree for insertion
      IndexTreePath<E> subtree = choosePath(getRootPath(), entry, height, 1);
  
      if(getLogger().isDebugging()) {
        getLogger().debugFine("insertion-subtree " + subtree);
      }
  
      N parent = getNode(subtree.getEntry());
      parent.addLeafEntry(entry);
      writeNode(parent);
  
      // adjust the tree from subtree to root
      adjustTree(subtree);
    }