public boolean updateLeader(final String groupId, final String leaderStr) {
        Requires.requireTrue(!StringUtils.isBlank(groupId), "Blank group id");
        Requires.requireTrue(!StringUtils.isBlank(leaderStr), "Blank leader");

        final PeerId leader = new PeerId();
        if (leader.parse(leaderStr)) {
            return updateLeader(groupId, leader);
        } else {
            LOG.error("Fail to parse leaderStr: {}", leaderStr);
            return false;
        }
    }
Update leader info.

@param groupId   raft group id
@param leaderStr peer string of leader
@return true on success
jraft-core/src/main/java/com/alipay/sofa/jraft/RouteTable.java