将byte[]从xls转换为xlsx文件并保存

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.ByteArrayInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;

public class XlsToXlsxConverter {
    public static void convert(byte[] xlsData, String outputPath) throws Exception {
        // 将byte[]转换为InputStream
        InputStream inputStream = new ByteArrayInputStream(xlsData);

        // 打开Excel文件
        Workbook workbook = WorkbookFactory.create(inputStream);

        // 创建新的XSSFWorkbook对象
        Workbook xlsxWorkbook = new XSSFWorkbook();

        // 遍历原始工作簿中的工作表
        for (int i = 0; i < workbook.getNumberOfSheets(); i++) {
            Sheet sheet = workbook.getSheetAt(i);
            Sheet xlsxSheet = xlsxWorkbook.createSheet(sheet.getSheetName());

            // 复制原始工作表中的行和单元格到新的工作表
            for (int j = 0; j <= sheet.getLastRowNum(); j++) {
                Row row = sheet.getRow(j);
                Row xlsxRow = xlsxSheet.createRow(j);

                for (int k = 0; k < row.getLastCellNum(); k++) {
                    Cell cell = row.getCell(k);
                    Cell xlsxCell = xlsxRow.createCell(k);

                    // 复制单元格的值和样式
                    xlsxCell.setCellValue(cell.getStringCellValue());
                    xlsxCell.setCellStyle(cell.getCellStyle());
                }
            }
        }

        // 将新的Excel文件保存到磁盘
        FileOutputStream outputStream = new FileOutputStream(outputPath);
        xlsxWorkbook.write(outputStream);
        outputStream.close();

        // 清理资源
        workbook.close();
        xlsxWorkbook.close();
    }

    public static void main(String[] args) {
        try {
            // 假设xlsData是从xls文件中读取的byte[]数据
            byte[] xlsData = /* 从xls文件中读取的byte[]数据 */;
            String outputPath = "output.xlsx";

            convert(xlsData, outputPath);
            System.out.println("转换完成，保存为：" + outputPath);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}