/**
	 * Set the length of the body in bytes, as specified by the
	 * {@code Content-Length} header.
	 */
	public void setContentLength(long contentLength) {
		set(CONTENT_LENGTH, Long.toString(contentLength));
	}

	/**
	 * Return the length of the body in bytes, as specified by the
	 * {@code Content-Length} header.
	 * <p>Returns -1 when the content-length is unknown.
	 */
	public long getContentLength() {
		String value = getFirst(CONTENT_LENGTH);
		return (value != null ? Long.parseLong(value) : -1);
	}

	@Override
	protected ClientHttpResponse executeInternal(HttpHeaders headers) throws IOException {
		byte[] bytes = this.bufferedOutput.toByteArrayUnsafe();
		if (headers.getContentLength() < 0) {
			headers.setContentLength(bytes.length);
		}
		ClientHttpResponse result = executeInternal(headers, bytes);
		this.bufferedOutput.reset();
		return result;
	}