java - What is the best way to get the count/length/size of an iterator?

Question

Is there a "computationally" quick way to get the count of an iterator?

int i = 0;
for ( ; some_iterator.hasNext() ; ++i ) some_iterator.next();

... seems like a waste of CPU cycles.

Answer 1

Using Guava library:

int size = Iterators.size(iterator);

Internally it just iterates over all elements so its just for convenience.