java查询influxDB数据导出excel文件

要在Java中从InfluxDB查询数据并导出到Excel文件，您可以使用以下步骤：

1. 导入InfluxDB Java客户端库和Apache POI库（用于创建和写入Excel文件）。

import org.influxdb.InfluxDB;
import org.influxdb.InfluxDBFactory;
import org.influxdb.dto.Query;
import org.influxdb.dto.QueryResult;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

2. 创建InfluxDB客户端并连接到InfluxDB数据库。

InfluxDB influxDB = InfluxDBFactory.connect("http://localhost:8086", "username", "password");
influxDB.setDatabase("mydb");

3. 创建InfluxDB查询并执行查询。

Query query = new Query("SELECT * FROM mymeasurement WHERE time > now() - 1d", "mydb");
QueryResult result = influxDB.query(query);

4. 创建Excel工作簿和工作表，并将查询结果写入Excel文件。

Workbook workbook = new XSSFWorkbook();
Sheet sheet = workbook.createSheet("Data");

int rowNum = 0;
for (QueryResult.Result queryResult : result.getResults()) {
    for (QueryResult.Series series : queryResult.getSeries()) {
        Row headerRow = sheet.createRow(rowNum++);
        int cellNum = 0;
        for (String column : series.getColumns()) {
            Cell cell = headerRow.createCell(cellNum++);
            cell.setCellValue(column);
        }
        for (List<Object> values : series.getValues()) {
            Row row = sheet.createRow(rowNum++);
            int cellNum2 = 0;
            for (Object value : values) {
                Cell cell = row.createCell(cellNum2++);
                cell.setCellValue(value.toString());
            }
        }
    }
}

// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("output.xlsx");
workbook.write(fileOut);
fileOut.close();

完整代码示例：

import org.influxdb.InfluxDB;
import org.influxdb.InfluxDBFactory;
import org.influxdb.dto.Query;
import org.influxdb.dto.QueryResult;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;

public class InfluxDBToExcel {

    public static void main(String[] args) throws IOException {
        // Connect to InfluxDB
        InfluxDB influxDB = InfluxDBFactory.connect("http://localhost:8086", "username", "password");
        influxDB.setDatabase("mydb");

        // Query data from InfluxDB
        Query query = new Query("SELECT * FROM mymeasurement WHERE time > now() - 1d", "mydb");
        QueryResult result = influxDB.query(query);

        // Write data to Excel file
        Workbook workbook = new XSSFWorkbook();
        Sheet sheet = workbook.createSheet("Data");

        int rowNum = 0;
        for (QueryResult.Result queryResult : result.getResults()) {
            for (QueryResult.Series series : queryResult.getSeries()) {
                Row headerRow = sheet.createRow(rowNum++);
                int cellNum = 0;
                for (String column : series.getColumns()) {
                    Cell cell = headerRow.createCell(cellNum++);
                    cell.setCellValue(column);
                }
                for (List<Object> values : series.getValues()) {
                    Row row = sheet.createRow(rowNum++);
                    int cellNum2 = 0;
                    for (Object value : values) {
                        Cell cell = row.createCell(cellNum2++);
                        cell.setCellValue(value.toString());
                    }
                }
            }
        }

        // Write the output to a file
        FileOutputStream fileOut = new FileOutputStream("output.xlsx");
        workbook.write(fileOut);
        fileOut.close();

        influxDB.close();
    }
}

请注意，此示例仅适用于使用InfluxDB 2.0及更高版本。如果您使用的是旧版本，请使用旧版InfluxDB Java客户端库并相应地更改查询语法和结果处理代码。