/**
  * Retrieves a Field object for a given field on the specified class, having set it accessible.
  *
  * @param cls the Class on which the field is expected to be defined
  * @param fieldName the name of the field of interest
  * @throws NoSuchFieldException in case of any error retriving information about the field
  */
 private static Field getField(Class cls, String fieldName) throws NoSuchFieldException {
   try {
     Field field = cls.getDeclaredField(fieldName);
     field.setAccessible(true);
     return field;
   } catch (NoSuchFieldException nsfe) {
     NoSuchFieldException e =
         new NoSuchFieldException(getMessage("classloaderutil.errorGettingField", fieldName));
     e.initCause(nsfe);
     throw e;
   }
 }