code: public static List<Pattern> convert(final List<String> patternStrings, final String prepend) {
  
          // Check sanity
          List<String> effectivePatternStrings = patternStrings;
          if (patternStrings == null) {
              effectivePatternStrings = new ArrayList<String>();
              effectivePatternStrings.add(".*");
          }
          final String effectivePrepend = prepend == null ? "" : prepend;
  
          // Convert
          final List<Pattern> toReturn = new ArrayList<Pattern>();
          for (String current : effectivePatternStrings) {
              toReturn.add(Pattern.compile(effectivePrepend + current, Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE));
          }
  
          // All done.
          return toReturn;
      }
docs: Collects a List containing {@code java.text.Pattern} objects by concatenating
  {@code prepend + current_pattern_string} and Pattern-compiling the result.
  
  @param patternStrings The List of PatternStrings to compile.
  @param prepend        A string to prepend each pattern. If a null argument is supplied, nothing
  will be prepended.
  @return a List containing {@code java.text.Pattern} objects by concatenating
  {@code prepend + current_pattern_string} and Pattern-compiling the result.