public class KeyPairTest {
  IKeyPair keyPair = Seed.createKeyPair(TestFixtures.master_seed_bytes);

  @Test
  public void testVerify() {
    assertTrue(
        keyPair.verify(
            TestFixtures.master_seed_bytes, Hex.decode(TestFixtures.singed_master_seed_bytes)));
  }

  @Test
  public void sanityTestSignAndVerify() {
    assertTrue(
        keyPair.verify(
            TestFixtures.master_seed_bytes, keyPair.sign(TestFixtures.master_seed_bytes)));
  }

  @Test
  public void testDerivationFromSeedBytes() {
    assertEquals(
        "0330E7FC9D56BB25D6893BA3F317AE5BCF33B3291BD63DB32654A313222F7FD020", keyPair.pubHex());
    assertEquals(
        "1ACAAEDECE405B2A958212629E16F2EB46B153EEE94CDD350FDEFF52795525B7", keyPair.privHex());
  }

  @Test
  public void testDerivationFromString() {
    IKeyPair keyPairFromSeed = AccountID.keyPairFromSeedString(TestFixtures.master_seed);
    assertEquals(
        "0330E7FC9D56BB25D6893BA3F317AE5BCF33B3291BD63DB32654A313222F7FD020",
        keyPairFromSeed.pubHex());
    assertEquals(
        "1ACAAEDECE405B2A958212629E16F2EB46B153EEE94CDD350FDEFF52795525B7",
        keyPairFromSeed.privHex());
  }
}
 public Account accountFromSeed(String masterSeed) {
   IKeyPair kp = Seed.fromBase58(masterSeed).keyPair();
   return account(AccountID.fromKeyPair(kp), kp);
 }