code: protected void config() {
  		objectMapper.configure(com.fasterxml.jackson.core.JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
  		objectMapper.configure(com.fasterxml.jackson.core.JsonParser.Feature.ALLOW_BACKSLASH_ESCAPING_ANY_CHARACTER, true);
  	}
docs: https://gitee.com/jfinal/jfinal-weixin/issues/I875U