code: protected String findStringInFile(String regexp, File fileToSearch) throws Exception {
          String foundString = null;
          List<String> matches = findStringsInFileCommon(regexp, true, -1, fileToSearch);
  
          if (matches != null && !matches.isEmpty()) {
              foundString = matches.get(0);
          }
  
          return foundString;
  
      }
docs: Searches the given file for the given regular expression.
  
  @param regexp
  a regular expression (or just a text snippet) to search for
  @param fileToSearch
  the file to search
  @return The first line which includes the pattern, or null if the pattern
  isn't found or if the file doesn't exist
  @throws Exception