private UnfoundPeerId findPeer(final PeerId peerId, final List<UnfoundPeerId> peers, final int posHint) {
        if (posHint < 0 || posHint >= peers.size() || !peers.get(posHint).peerId.equals(peerId)) {
            for (final UnfoundPeerId ufp : peers) {
                if (ufp.peerId.equals(peerId)) {
                    return ufp;
                }
            }
            return null;
        }

        return peers.get(posHint);
    }
Init the ballot with current conf and old conf.

@param conf    current configuration
@param oldConf old configuration
@return true if init success
jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Ballot.java