code: public <X extends Exception> RuntimeException rethrow(Throwable e, Class<X> declaredType)
        throws IOException, X {
      checkNotNull(e);
      thrown = e;
      Throwables.propagateIfPossible(e, IOException.class);
      Throwables.propagateIfPossible(e, declaredType);
      throw new RuntimeException(e);
    }
docs: Stores the given throwable and rethrows it. It will be rethrown as is if it is an {@code
  IOException}, {@code RuntimeException}, {@code Error} or a checked exception of the given type.
  Otherwise, it will be rethrown wrapped in a {@code RuntimeException}. <b>Note:</b> Be sure to
  declare all of the checked exception types your try block can throw when calling an overload of
  this method so as to avoid losing the original exception type.
  
  <p>This method always throws, and as such should be called as {@code throw closer.rethrow(e,
  ...);} to ensure the compiler knows that it will throw.
  
  @return this method does not return; it always throws
  @throws IOException when the given throwable is an IOException
  @throws X when the given throwable is of the declared type X