创建一个excel文件所需要的代码

1，首先是依赖

<!-- POI EXCEL 文件读写 -->
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>4.1.2</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-excelant</artifactId>
    <version>4.1.2</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>4.1.2</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml-schemas</artifactId>
    <version>4.1.2</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-scratchpad</artifactId>
    <version>4.1.2</version>
</dependency>

2.其次是创建表，行，填充，导出

// 设置响应内容类型和文件名
response.setHeader("Content-Disposition", "attachment; filename=\"order.xlsx\"");
response.setHeader("Access-Control-Allow-Origin", "*");

// 创建Excel工作簿
Workbook workbook = new XSSFWorkbook();
Sheet sheet = workbook.createSheet("用户信息");

// 创建表头
Row headerRow = sheet.createRow(0);
headerRow.createCell(0).setCellValue("创建时间");
headerRow.createCell(1).setCellValue("订单号");
headerRow.createCell(2).setCellValue("用户ID");

//填充信息
row.createCell(0).setCellValue(String.valueOf(order.getCreateTime()));
row.createCell(1).setCellValue(order.getOrderSn());
row.createCell(2).setCellValue(String.valueOf(order.getUserId()));

// 导出Excel
try {
    workbook.write(response.getOutputStream());
    workbook.close();
} catch (IOException e) {
    e.printStackTrace();
}

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