code: @FFDCIgnore({IOException.class})
      public static InputStream getResourceAsStream(String resourceName, Class<?> callingClass) {
          URL url = getResource(resourceName, callingClass);
  
          try {
              return (url != null) ? url.openStream() : null;
          } catch (IOException e) {
              return null;
          }
      }
docs: This is a convenience method to load a resource as a stream. <p/> The
  algorithm used to find the resource is given in getResource()
  
  @param resourceName The name of the resource to load
  @param callingClass The Class object of the calling object