java - Bouncy castle no such provider exception -

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i have added bouncy castle jar file application class path in android , in java. code i've used in both of them. doesn't seem recognize provider "bc". 

securerandom sr1=new securerandom().getinstance("sha1prng", "bc");       system.out.println(sr1.getprovider());       sr1.setseed(12);       byte[] a=new byte[0];       sr1.nextbytes(a);       int ai=a[0];       system.out.println(ai);


throws following exception in both android , in java:

java.security.nosuchproviderexception: no such provider: bc


how correct this?
had not added provider in policy file. after doing getting following exception.

java.security.nosuchalgorithmexception: no such algorithm: sha1prng provider  bc<br>

does mean bouncy castle not provide implementation of "sha1prng" algorithm? whole reason imported bouncy castle have common provider in both android , in java, sequence of random numbers generated same seed same in both android , java.

apparently doesn't provide securerandom implementation @ all. can system implementation (from harmony) (no need create instance call static method): 

securerandom.getinstance("sha1prng")

bouncycastle has digestrandomgenerator used in similar manner, may or may not compatible sun sha1prng (which appears proprietary, , defined)

re: generating otps using securerandom: securerandom fixed seed not right tool this. generate otps, should use secret key combined predictable element (time or counter). standard way using hmac specified e.g. oath. read rfc 4226 details.


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