google app engine - Objectify/AppEngine: best way to count # of objects returned by a query? -


what best (i.e. efficient) way of counting number of objects returned query, w/o loading them, using objectify on appengine? i'm guessing best fetch keys , counting result:

public int getentitycount(long v) {     objectify ofy = objectifyservice.begin();     iterable<key<myentity>> list = ofy.query(myentity.class)             .filter("field", v).fetchkeys();     int n = 0;     (key<myentity> e : list)         n++;     return n; }

doesn't seems have dedicated method doing that. ideas?

found it:

int n = iterable<key<myentity>> list = ofy().query(myentity.class)       .filter("field", v).count();

it's simple, though efficient because retrieves keys. it's better design ui handle unknown numbers of results (such google gives clues number of pages not actual number)


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