question on filters from head first

Filters support a initialization mechanism that includes an init() method that is gauranteed to be called before the filter is used to handle requests

Is this statement true or false

The book states it as false

I think it is true .. some please clarify

It is given as one of the options for question no 5 page no 703 in the head first book

Thanks

Servlet Specification:

The container must ensure that it has instantiated a filter of the appropriate
class for each filter in the list, and called its init(FilterConfig config)
method. The filter may throw an exception to indicate that it cannot function
properly. If the exception is of type UnavailableException, the container may
examine the isPermanent attribute of the exception and may choose to retry the
filter at some later time.

Thanks,

The filter may throw an exception to indicate that it cannot function
properly

Thanks for the details from spec chandra.

The presence of aforesaid particular statement make the question posted by OP become "false". Is that right?

The question only asks if the init() method is called or not ... rather than completes or not !!

So... i think its still true even in the light of the new info !!!

But the book says its false !!

So need more clarifications !!

Thanks

What happens when you try to code these situations yourself? What behavior do you observe?