code: @Nonnull
    public static ESuccess writeStream (@WillClose @Nonnull final OutputStream aOS,
                                        @Nonnull final byte [] aBuf,
                                        @Nonnegative final int nOfs,
                                        @Nonnegative final int nLen)
    {
      try
      {
        ValueEnforcer.notNull (aOS, "OutputStream");
        ValueEnforcer.isArrayOfsLen (aBuf, nOfs, nLen);
  
        aOS.write (aBuf, nOfs, nLen);
        aOS.flush ();
        return ESuccess.SUCCESS;
      }
      catch (final IOException ex)
      {
        LOGGER.error ("Failed to write to output stream", ex instanceof IMockException ? null : ex);
        return ESuccess.FAILURE;
      }
      finally
      {
        close (aOS);
      }
    }
docs: Write bytes to an {@link OutputStream}.
  
  @param aOS
  The output stream to write to. May not be <code>null</code>. Is closed
  independent of error or success.
  @param aBuf
  The byte array from which is to be written. May not be
  <code>null</code>.
  @param nOfs
  The 0-based index to the first byte in the array to be written. May
  not be &lt; 0.
  @param nLen
  The non-negative amount of bytes to be written. May not be &lt; 0.
  @return {@link ESuccess}