code: @Override
      public void readHeader(RandomAccessFile file) throws IOException {
          super.readHeader(file);
          this.k_max = file.readInt();
      }
docs: Initializes this header from the specified file.
  Calls {@link de.lmu.ifi.dbs.elki.index.tree.TreeIndexHeader#readHeader(java.io.RandomAccessFile)
  TreeIndexHeader#readHeader(file)} and reads additionally the integer value of
  {@link #k_max}
  from the file.