code: public static void checkLoaded() {
      if (LOAD_ERROR != null) {
        throw LOAD_ERROR;
      }
      // Make a test call, sometimes the error won't occur until you try the native method.
      // 2 ^ 3 = 8, 8 mod 5 = 3
      BigInteger two = BigInteger.valueOf(2);
      BigInteger three = BigInteger.valueOf(3);
      BigInteger four = BigInteger.valueOf(4);
      BigInteger five = BigInteger.valueOf(5);
      BigInteger answer;
  
      answer = modPowInsecure(two, three, five);
      if (!three.equals(answer)) {
        throw new AssertionError("libgmp is loaded but modPowInsecure returned the wrong answer");
      }
  
      answer = modPowSecure(two, three, five);
      if (!three.equals(answer)) {
        throw new AssertionError("libgmp is loaded but modPowSecure returned the wrong answer");
      }
  
      int answr = kronecker(four, five);
      if (answr != 1) {
        throw new AssertionError("libgmp is loaded but kronecker returned the wrong answer");
      }
    }
docs: Verifies this library is loaded properly.
  
  @throws UnsatisfiedLinkError if the library failed to load properly.