code: public static void handleCauseUnchecked(final ExecutionException ex) {
          final ConcurrentRuntimeException crex = extractCauseUnchecked(ex);
  
          if (crex != null) {
              throw crex;
          }
      }
docs: Handles the specified {@code ExecutionException} and transforms it into a
  runtime exception. This method works exactly like
  {@link #handleCause(ExecutionException)}, but instead of a
  {@link ConcurrentException} it throws a
  {@link ConcurrentRuntimeException}. This is an alternative for client
  code that does not want to deal with checked exceptions.
  
  @param ex the exception to be handled
  @throws ConcurrentRuntimeException if the cause of the {@code
  ExecutionException} is a checked exception; this exception is then
  wrapped in the thrown runtime exception