code: public JsonWriter writeValue(String value) throws IOException {
          if (!willWriteValue) {
              indent();
          }
          writer.write(escape(value));
          willWriteValue = false;
          return this;
      }
docs: Writes a string to a character stream.
  If {@code value} is null, write a null string ("").
  
  @param value the string to write to a character-output stream
  @return this JsonWriter
  @throws IOException if an I/O error has occurred