@Override
  public void close() throws IOException {
    if (this.level != 0) {
      throw new IllegalStateException("Document finished with unbalanced start and end objects");
    }
    if (this.out instanceof Writer) {
      ((Writer) this.out).flush();
    }
  }
Whether a {@link Tokens#VALUE_SEPARATOR} needs to be printed before the beginning of the next object.
nbt/src/main/java/net/kyori/adventure/nbt/TagStringWriter.java