code: @Override
      public void write(char[] cbuf, int off, int len) throws IOException {
          List<Exception> writeExceptions = new ArrayList<>(delegates.size());
          for (Writer delegate : delegates) {
              try {
                  delegate.write(cbuf, off, len);
              } catch (IOException | RuntimeException writeException) {
                  writeExceptions.add(writeException);
              }
          }
          if (!writeExceptions.isEmpty()) {
              throw mergeExceptions("writing", writeExceptions);
          }
      }
docs: Delegates the write operation to all delegates and merges any occurred exceptions into a single {@link IOException}.
  
  @param cbuf The buffer containing the characters to be written.
  @param off  The offset index to write from.
  @param len  The number of characters to write.
  @throws IOException in case at least one of the delegate writers threw an exception while writing.
  <em>Please note:</em> It is very well possible that other delegates were succesfully written.