code: public Set<String> getAllTypes() {
          Set<String> allTypes = Sets.newHashSet(store.getAll(index(SubTypesScanner.class), Object.class.getName()));
          if (allTypes.isEmpty()) {
              throw new ReflectionsException("Couldn't find subtypes of Object. " +
                      "Make sure SubTypesScanner initialized to include Object class - new SubTypesScanner(false)");
          }
          return allTypes;
      }
docs: get all types scanned. this is effectively similar to getting all subtypes of Object.
  <p>depends on SubTypesScanner configured with {@code SubTypesScanner(false)}, otherwise {@code ReflectionsException} is thrown
  <p><i>note using this might be a bad practice. it is better to get types matching some criteria,
  such as {@link #getSubTypesOf(Class)} or {@link #getTypesAnnotatedWith(Class)}</i>
  @return Set of String, and not of Class, in order to avoid definition of all types in PermGen