code: @SuppressWarnings("resource")
      public static byte[] readFile(String filename) throws IOException {
  
          // create input and output stream
          InputStream in = CmsFileUtil.class.getClassLoader().getResourceAsStream(filename);
          if (in == null) {
              throw new FileNotFoundException(filename);
          }
  
          return readFully(in);
      }
docs: Reads a file with the given name from the class loader and returns the file content.<p>
  
  @param filename the file to read
  @return the read file content
  
  @throws IOException in case of file access errors