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[English](./README.md) | [中文](./README-zh.md)
# TsFile Java Document
<p align="center">
  <img src="https://www.apache.org/logos/originals/tsfile.svg"
       alt="TsFile Logo"
       width="400"/>
</p>

## 使用

### 在 Maven 中添加 TsFile 依赖

当前发布版本是 `2.1.0`，可以这样引用

```xml  
<dependencies>
    <dependency>
      <groupId>org.apache.tsfile</groupId>
      <artifactId>tsfile</artifactId>
      <version>2.1.0</version>
    </dependency>
<dependencies>
```


### TsFile Java API

#### 数据写入

数据写入主要通过 TsFileWriter 完成。

1. 创建 TsFileWriter

   ```java
    File f = new File("test.tsfile");
    TsFileWriter tsFileWriter = new TsFileWriter(f);
    ```

2. 注册时间序列
    
   ```java
   List<MeasurementSchema> schema1 = new ArrayList<>();
   schemas.add(new MeasurementSchema("电压", TSDataType.FLOAT));
   schemas.add(new MeasurementSchema("电流", TSDataType.FLOAT));
   tsFileWriter.registerTimeseries(new Path("太阳能板1"), schema1);
   
   List<MeasurementSchema> schema2 = new ArrayList<>();
   schemas.add(new MeasurementSchema("电压", TSDataType.FLOAT));
   schemas.add(new MeasurementSchema("电流", TSDataType.FLOAT));
   schemas.add(new MeasurementSchema("风速", TSDataType.FLOAT));
   tsFileWriter.registerTimeseries(new Path("风机1"), schema2);
   ```

3. 写入数据
  
    ```java
   TSRecord tsRecord = new TSRecord(1, "太阳能板1");
   tsRecord.addTuple(DataPoint.getDataPoint(TSDataType.FLOAT, "电压", 1.1f));
   tsRecord.addTuple(DataPoint.getDataPoint(TSDataType.FLOAT, "电流", 2.2f));
   tsFileWriter.write(tsRecord);
   ```

4. 调用`close`方法来关闭文件，关闭后才能进行查询。

    ```java
    tsFileWriter.close();
    ```

写入 TsFile 完整示例

[构造 TSRecord 来写入数据](../examples/src/main/java/org/apache/tsfile/TsFileWriteAlignedWithTSRecord.java)。

[构造 Tablet 来写入数据](../examples/src/main/java/org/apache/tsfile/TsFileWriteAlignedWithTablet.java)。


#### 数据查询

数据查询主要通过 TsFileReader 完成。

1. 创建 TsFileReader

   ```java
   TsFileSequenceReader reader = new TsFileSequenceReader(path);
   TsFileReader tsFileReader = new TsFileReader(reader)；
   ```

2. 构造查询条件

   ```java
      ArrayList<Path> paths = new ArrayList<>();
      paths.add(new Path("太阳能板1", "电压"));
      paths.add(new Path("太阳能板1", "电流"));
   
      IExpression timeFilter = BinaryExpression.and(
      new GlobalTimeExpression(TimeFilterApi.gtEq(1L)),
      new GlobalTimeExpression(TimeFilterApi.ltEq(10L)));
   
      QueryExpression queryExpression = QueryExpression.create(paths, timeFilter);
   ```

3. 查询数据

   ```java
   QueryDataSet queryDataSet = readTsFile.query(queryExpression);
   while (queryDataSet.hasNext()) {
        queryDataSet.next();
   }
   ```

4. 关闭文件

   ```java
   tsFileReader.close();
   ```

读取 TsFile 完整示例

[查询数据](../examples/src/main/java/org/apache/tsfile/TsFileRead.java)

[全文件读取](../examples/src/main/java/org/apache/tsfile/TsFileSequenceRead.java)


## 开发

### 前置条件

构建 Java 版的 TsFile，必须要安装以下依赖:

1. Java >= 17. 请确保设置了环境变量.
2. Maven >= 3.6.3 (如果要从源代码编译TsFile).


### 使用 maven 构建

```
mvn clean package -P with-java -DskipTests
```

### 安装到本地机器

```
mvn install -P with-java -DskipTests
```
