启动AzkabanWebServer报如下错误：

点击进入 ActiveExecutors.setupExecutors发现调用的是

loadExecutors（）继续深入

private ImmutableSet<Executor> loadExecutors() throws ExecutorManagerException {
  logger.info("Initializing executors from database.");
  return ImmutableSet.copyOf(this.executorLoader.fetchActiveExecutors());
}

继续深入调用JdbcExecutorLoader的fetchActiveExecutors方法

public List<Executor> fetchActiveExecutors() throws ExecutorManagerException {
  return this.executorDao.fetchActiveExecutors();
}

继续深入调用DAO方法

List<Executor> fetchActiveExecutors() throws ExecutorManagerException {
  try {
    return this.dbOperator
        .query(FetchExecutorHandler.FETCH_ACTIVE_EXECUTORS, new FetchExecutorHandler());