code: @Override
    public String getOptStringProperty(final String name) throws OptionsException {
      Object val = getOptProperty(name);
  
      if (val == null) {
        return null;
      }
  
      if (!(val instanceof String)) {
        throw new OptionsException("org.bedework.calenv.bad.option.value");
      }
  
      return (String)val;
    }
docs: Get optional property.
  
  @param name String property name
  @return String value
  @throws OptionsException