A divide by zero bug in LoadBalancingKMSClientProvider.java

@Override
public KeyVersion rollNewVersion(final String name, final byte[] material)
    throws IOException {
    final KeyVersion newVersion = doOp(new ProviderCallable<KeyVersion>() {
      @Override
      public KeyVersion call(KMSClientProvider provider) throws IOException {
        return provider.rollNewVersion(name, material);
      }
    }, nextIdx(), false);
    ...
}

private int nextIdx() {
    while (true) {
      int current = currentIdx.get();
      int next = (current + 1) % providers.length;
      ......
}

private <T> T doOp(ProviderCallable<T> op, int currPos,
      boolean isIdempotent) throws IOException {
    if (providers.length == 0) {
      throw new IOException("No providers configured !");
    }
    ...
}