Java tutorial
import java.math.BigInteger; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.PrivateKey; import java.security.PublicKey; import java.security.interfaces.DSAParams; import java.security.interfaces.DSAPrivateKey; import java.security.interfaces.DSAPublicKey; import java.security.spec.DSAPrivateKeySpec; import java.security.spec.DSAPublicKeySpec; import java.security.spec.KeySpec; public class Main { public static void main(String[] argv) throws Exception { KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA"); keyGen.initialize(1024); KeyPair keypair = keyGen.genKeyPair(); DSAPrivateKey privateKey = (DSAPrivateKey) keypair.getPrivate(); DSAPublicKey publicKey = (DSAPublicKey) keypair.getPublic(); DSAParams dsaParams = privateKey.getParams(); BigInteger p = dsaParams.getP(); BigInteger q = dsaParams.getQ(); BigInteger g = dsaParams.getG(); BigInteger x = privateKey.getX(); BigInteger y = publicKey.getY(); KeyFactory keyFactory = KeyFactory.getInstance("DSA"); KeySpec publicKeySpec = new DSAPublicKeySpec(y, p, q, g); PublicKey publicKey1 = keyFactory.generatePublic(publicKeySpec); } }