| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 |
| * |
| * http://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 org.apache.iotdb.db.queryengine.execution.aggregation.timerangeiterator; |
| |
| import org.apache.iotdb.tsfile.read.common.TimeRange; |
| |
| /** Used for aggregation with only one time window. i.e. Aggregation without group by. */ |
| public class SingleTimeWindowIterator implements ITimeRangeIterator { |
| |
| // total query [startTime, endTime) |
| private final long startTime; |
| private final long endTime; |
| |
| private TimeRange curTimeRange; |
| private boolean hasCachedTimeRange; |
| |
| public SingleTimeWindowIterator(long startTime, long endTime) { |
| this.startTime = startTime; |
| this.endTime = endTime; |
| } |
| |
| @Override |
| public TimeRange getFirstTimeRange() { |
| return new TimeRange(startTime, endTime); |
| } |
| |
| @Override |
| public boolean hasNextTimeRange() { |
| if (hasCachedTimeRange) { |
| return true; |
| } |
| if (curTimeRange == null) { |
| curTimeRange = getFirstTimeRange(); |
| hasCachedTimeRange = true; |
| } |
| return hasCachedTimeRange; |
| } |
| |
| @Override |
| public TimeRange nextTimeRange() { |
| if (hasCachedTimeRange || hasNextTimeRange()) { |
| hasCachedTimeRange = false; |
| return curTimeRange; |
| } |
| return null; |
| } |
| |
| @Override |
| public boolean isAscending() { |
| return false; |
| } |
| |
| @Override |
| public long currentOutputTime() { |
| // display time as 0 in aggregation result |
| return curTimeRange.getMin() == Long.MIN_VALUE ? 0 : curTimeRange.getMin(); |
| } |
| |
| @Override |
| public long getTotalIntervalNum() { |
| return 1; |
| } |
| } |