}
    }
  }

  /**
   * Writes all the text from the given {@link Readable} (such as a {@link Reader}) to this sink.
   * Does not close {@code readable} if it is {@code Closeable}.
   *
   * @return the number of characters written
   * @throws IOException if an I/O error occurs while reading from {@code readable} or writing to
   *     this sink
   */
  @CanIgnoreReturnValue

    assertEquals("", sink.getString());
    sink.write(STRING);

    assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());
    assertEquals(STRING, sink.getString());
  }

  public void testWriteFrom_reader() throws IOException {
    StringReader reader = new StringReader(STRING);
    sink.writeFrom(reader);

    assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());

  protected ByteSink() {}

  /**
   * Returns a {@link CharSink} view of this {@code ByteSink} that writes characters to this sink as
   * bytes encoded with the given {@link Charset charset}.
   */
  public CharSink asCharSink(Charset charset) {
    return new AsCharSink(charset);
  }

  /**
   * Opens a new {@link OutputStream} for writing to this sink. This method returns a new,
   * independent stream each time it is called.

    TestCharSink sink = new TestCharSink();

    assertFalse(sink.wasStreamOpened() || sink.wasStreamClosed());

    assertEquals(STRING.length(), source.copyTo(sink));
    assertTrue(source.wasStreamOpened() && source.wasStreamClosed());
    assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());

    assertEquals(STRING, sink.getString());
  }

   *
   * <ul>
   *   <li>use {@link StringReader} instead of {@link CharSequenceReader}. It is faster since it can
   *       use {@link String#getChars(int, int, char[], int)} instead of copying characters one by
   *       one with {@link CharSequence#charAt(int)}.
   *   <li>use {@link Appendable#append(CharSequence)} in {@link #copyTo(Appendable)} and {@link

   * and may affect the behavior of the returned sink and the streams it provides. See {@link
   * StandardOpenOption} for the standard options that may be provided. Providing no options is
   * equivalent to providing the {@link StandardOpenOption#CREATE CREATE}, {@link
   * StandardOpenOption#TRUNCATE_EXISTING TRUNCATE_EXISTING} and {@link StandardOpenOption#WRITE
   * WRITE} options.
   */

   * and may affect the behavior of the returned sink and the streams it provides. See {@link
   * StandardOpenOption} for the standard options that may be provided. Providing no options is
   * equivalent to providing the {@link StandardOpenOption#CREATE CREATE}, {@link
   * StandardOpenOption#TRUNCATE_EXISTING TRUNCATE_EXISTING} and {@link StandardOpenOption#WRITE
   * WRITE} options.
   */

/// info

Alternativ kann `status_code` auch ein `IntEnum` erhalten, so wie Pythons <a href="https://docs.python.org/3/library/http.html#http.HTTPStatus" class="external-link" target="_blank">`http.HTTPStatus`</a>.

///

Das wird:

* Diesen Statuscode mit der Response zurücksenden.
* Ihn als solchen im OpenAPI-Schema dokumentieren (und somit in den Benutzeroberflächen):

r-bottom:1px solid #dee2e6;z-index:1034}.main-header .nav-link{height:2.5rem;position:relative}.main-header.text-sm .nav-link,.text-sm .main-header .nav-link{height:1.93725rem;padding:.35rem 1rem}.main-header.text-sm .nav-link>.fa,.main-header.text-sm .nav-link>.fab,.main-header.text-sm .nav-link>.fad,.main-header.text-sm .nav-link>.fal,.main-header.text-sm .nav-link>.far,.main-header.text-sm .nav-link>.fas,.main-header.text-sm .nav-link>.ion,.main-header.text-sm .nav-link>.svg-inline--fa,.text-sm...

.main-header .nav-link > .svg-inline--fa,\n.text-sm .main-header .nav-link > .ion, .main-header.text-sm .nav-link > .fa,\n.main-header.text-sm .nav-link > .fas,\n.main-header.text-sm .nav-link > .far,\n.main-header.text-sm .nav-link > .fab,\n.main-header.text-sm .nav-link > .fal,\n.main-header.text-sm .nav-link > .fad,\n.main-header.text-sm .nav-link > .svg-inline--fa,\n.main-header.text-sm .nav-link > .ion {\n  font-size: 0.875rem;\n}\n\n.main-header .navbar-nav .nav-item {\n  margin: 0;\n}\n\n.main-header...