107.4. Flink DataSet 콜백

@Bean
public DataSetCallback<Long> dataSetCallback() {
    return new DataSetCallback<Long>() {
        public Long onDataSet(DataSet dataSet, Object... objects) {
            try {
                 dataSet.print();
                 return new Long(0);
            } catch (Exception e) {
                 return new Long(-1);
            }
        }
    };
}