content: /*
   * Copyright 2022 The FeatHub Authors
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.feathub.flink.udf.processfunction;
  
  import org.apache.flink.types.Row;
  import org.apache.flink.util.Collector;
  
  import java.time.Instant;
  
  /**
   * SlidingWindowZeroValuedRowExpiredRowHandler output a row with the default values and the key from
   * the expired row when a row is expired.
   */
  public class SlidingWindowZeroValuedRowExpiredRowHandler implements SlidingWindowExpiredRowHandler {
  
      private final Row zeroValuedRow;
      private final String rowTimeFieldName;
      private final String[] keyFieldNames;
  
      public SlidingWindowZeroValuedRowExpiredRowHandler(
              Row zeroValuedRow, String rowTimeFieldName, String... keyFieldNames) {
          this.zeroValuedRow = zeroValuedRow;
          this.rowTimeFieldName = rowTimeFieldName;
          this.keyFieldNames = keyFieldNames;
      }
  
      @Override
      public void handleExpiredRow(Collector<Row> out, Row expiredRow, long currentTimestamp) {
          Row row = Row.copy(zeroValuedRow);
          row.setField(rowTimeFieldName, Instant.ofEpochMilli(currentTimestamp));
          for (String keyFieldName : keyFieldNames) {
              row.setField(keyFieldName, expiredRow.getField(keyFieldName));
          }
          out.collect(row);
      }
  }
  