Hello, The actual discussion on the OpenJDK list turned out to be a wrong understanding and the simple case of generating random bytes was enough for BigInteger.
However regarding RNG I can open requests, one would be for a RandomAdapter and the other would be to add a factory method for BigInteger (and possibly BigDecimal) to the Random Providers. (Or did. You mean only the Adapter?) Gruss Bernd -- http://bernd.eckenfels.net ________________________________ Von: Gilles <gil...@harfang.homelinux.org> Gesendet: Freitag, Dezember 21, 2018 4:43 PM An: dev@commons.apache.org Betreff: Re: [rng] Uniform big integers On Thu, 20 Dec 2018 17:30:44 +0100, Gilles wrote: > Hi. > > On Thu, 20 Dec 2018 15:15:55 +0000, Bernd Eckenfels wrote: >> Hello, >> >> I don’t know what the usecase is, it is motivated by a Bug about >> BigInteger(num, Random). I guess one of the users is actually the >> crypto usecase (starting with random numbers to find primes). >> >> I wanted to check how RNG deals with this > > You can do it by defining a bridge from [RNG] "UniformRandomProvider" > to "java.util.Random": > --- CUT (untested) --- > public class BridgeToRandom extends Random { > private final UniformRandomProvider delegate; > > public BridgeToRandom(UniformRandomProvider rng) { > delegate = rng; > } > > @Override > protected int next(int unused) { > return rng.nextInt(); > } > } > ---CUT--- > > Then, you can test all the generators implemented in [RNG]. FTR: In case you don't pursue it, please file a report on JIRA to keep track of this if we want to explore how it could extend the test suite. Thanks, Gilles > >> (since the additional need >> for generating a random bitlength looks unfamiliar but logical to >> me). >> Is it really not enough to fill all bits randomly (especially for >> the >> case where it is a 0 .. 2^n range only)? >> >> Discussion is here: >> >> http://mail.openjdk.java.net/pipermail/core-libs-dev/2018-December/057594.html >> >> Gruss >> Bernd >> -- >> http://bernd.eckenfels.net >> >> ________________________________ >> Von: Gilles <gil...@harfang.homelinux.org> >> Gesendet: Donnerstag, Dezember 20, 2018 2:16 PM >> An: dev@commons.apache.org >> Betreff: Re: [rng](site) broken source(current) link >> >> Hi. >> >> On Thu, 20 Dec 2018 12:43:51 +0000, Bernd Eckenfels wrote: >>> I wanted to check if RNG can construct uniformly distributed >>> BigIntegers and how it is doing it (answer: it doesn’t) >> >> It could be a feature request. >> [I guess that you mean "within a given range".] >> >> Being curious: What's the use-case for random "BigInteger"s? >> >>> while doing so >>> I noticed that the site link to the source is broken, maybe this is >>> due to git-wip migration? >> >> Yes. >> Thanks; fixed now. >> >>> >>> BTW: http://cr.openjdk.java.net/~bpb/8146153/webrev.01/index.html >> >> >> Regards, >> Gilles >> >>> >>> Gruss >>> Bernd >>> -- >>> http://bernd.eckenfels.net > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
