I would like to remove all non-alphanumerical characters from this string, and other types of strings like this one

```
Unable_to_locate_element_{"method""link_text","selector""ikljbhfvdesiofsdjkl"}

```

So I can use this string in order to generate a name for a screenshot in this code:

```
    private String generateRandomFilename(Throwable arg0) {
      Calendar c = Calendar.getInstance();

      String filename = arg0.getMessage();
      int i = filename.indexOf('\n');
      filename = filename.substring(0, i).replaceAll("\\s", "_").replaceAll(":", "") + ".jpg";
      filename = "" + c.get(Calendar.YEAR) + 
          "-" + c.get(Calendar.MONTH) + 
          "-" + c.get(Calendar.DAY_OF_MONTH) +
          "-" + c.get(Calendar.HOUR_OF_DAY) +
          "-" + c.get(Calendar.MINUTE) +
          "-" + c.get(Calendar.SECOND) +
          "-" + filename;

      return filename;
  }

```

The way it is now, my file creation breakes because of not all bad characters being removed.