checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    return hasRemaining() ? seq.charAt(pos++) : -1;
  }

  @Override
  public synchronized int read(char[] cbuf, int off, int len) throws IOException {
    checkPositionIndexes(off, off + len, cbuf.length);
    checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    if (!hasRemaining()) {
      return -1;

    checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    return hasRemaining() ? seq.charAt(pos++) : -1;
  }

  @Override
  public synchronized int read(char[] cbuf, int off, int len) throws IOException {
    checkPositionIndexes(off, off + len, cbuf.length);
    checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    if (!hasRemaining()) {
      return -1;

Je hoeft niet langer de verkeerde keys in te typen, op en neer te gaan tussen de documentatie, of heen en weer te scrollen om te checken of je `username` of toch `user_name` had gebruikt.

### Kort