| /* |
| * 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.tsfile; |
| |
| import org.apache.iotdb.tsfile.read.ReadOnlyTsFile; |
| import org.apache.iotdb.tsfile.read.TsFileSequenceReader; |
| import org.apache.iotdb.tsfile.read.common.Path; |
| import org.apache.iotdb.tsfile.read.expression.IExpression; |
| import org.apache.iotdb.tsfile.read.expression.QueryExpression; |
| import org.apache.iotdb.tsfile.read.expression.impl.BinaryExpression; |
| import org.apache.iotdb.tsfile.read.expression.impl.GlobalTimeExpression; |
| import org.apache.iotdb.tsfile.read.expression.impl.SingleSeriesExpression; |
| import org.apache.iotdb.tsfile.read.filter.TimeFilter; |
| import org.apache.iotdb.tsfile.read.filter.ValueFilter; |
| import org.apache.iotdb.tsfile.read.query.dataset.QueryDataSet; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| |
| /** |
| * The class is to show how to read TsFile file named "test.tsfile". The TsFile file "test.tsfile" |
| * is generated from class TsFileWriteWithTSRecord or TsFileWriteWithTablet. Run |
| * TsFileWriteWithTSRecord or TsFileWriteWithTablet to generate the test.tsfile first |
| */ |
| public class TsFileRead { |
| |
| private static final String DEVICE1 = "device_1"; |
| |
| private static void queryAndPrint( |
| ArrayList<Path> paths, ReadOnlyTsFile readTsFile, IExpression statement) throws IOException { |
| QueryExpression queryExpression = QueryExpression.create(paths, statement); |
| QueryDataSet queryDataSet = readTsFile.query(queryExpression); |
| while (queryDataSet.hasNext()) { |
| System.out.println(queryDataSet.next()); |
| } |
| System.out.println("------------"); |
| } |
| |
| public static void main(String[] args) throws IOException { |
| |
| // file path |
| String path = "test.tsfile"; |
| |
| // create reader and get the readTsFile interface |
| try (TsFileSequenceReader reader = new TsFileSequenceReader(path); |
| ReadOnlyTsFile readTsFile = new ReadOnlyTsFile(reader)) { |
| |
| // use these paths(all measurements) for all the queries |
| ArrayList<Path> paths = new ArrayList<>(); |
| paths.add(new Path(DEVICE1, "sensor_1")); |
| paths.add(new Path(DEVICE1, "sensor_2")); |
| paths.add(new Path(DEVICE1, "sensor_3")); |
| |
| // no filter, should select 1 2 3 4 6 7 8 |
| queryAndPrint(paths, readTsFile, null); |
| |
| // time filter : 4 <= time <= 10, should select 4 6 7 8 |
| IExpression timeFilter = |
| BinaryExpression.and( |
| new GlobalTimeExpression(TimeFilter.gtEq(4L)), |
| new GlobalTimeExpression(TimeFilter.ltEq(10L))); |
| queryAndPrint(paths, readTsFile, timeFilter); |
| |
| // value filter : device_1.sensor_2 <= 20, should select 1 2 4 6 7 |
| IExpression valueFilter = |
| new SingleSeriesExpression(new Path(DEVICE1, "sensor_2"), ValueFilter.ltEq(20L)); |
| queryAndPrint(paths, readTsFile, valueFilter); |
| |
| // time filter : 4 <= time <= 10, value filter : device_1.sensor_3 >= 20, should select 4 7 8 |
| timeFilter = |
| BinaryExpression.and( |
| new GlobalTimeExpression(TimeFilter.gtEq(4L)), |
| new GlobalTimeExpression(TimeFilter.ltEq(10L))); |
| valueFilter = |
| new SingleSeriesExpression(new Path(DEVICE1, "sensor_3"), ValueFilter.gtEq(20L)); |
| IExpression finalFilter = BinaryExpression.and(timeFilter, valueFilter); |
| queryAndPrint(paths, readTsFile, finalFilter); |
| } |
| } |
| } |