使用Apache POI导出Excel-优快云博客

本文链接：https://blog.youkuaiyun.com/Mensonge/article/details/105101163

导包

	<dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi-ooxml</artifactId>
        <version>3.16</version>
    </dependency>

创建ExportExcelUtils.java 导出工具类

public class ExportExcelUtils {

    public static void exportExcel(HttpServletResponse response, String fileName, ExcelData data) throws Exception {
        // 告诉浏览器用什么软件可以打开此文件
        response.setHeader("content-Type", "application/vnd.ms-excel");
        // 下载文件的默认名称
        response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "utf-8"));
        exportExcel(data, response.getOutputStream());
    }

    public static void exportExcel(ExcelData data, OutputStream out) throws Exception {

        XSSFWorkbook wb = new XSSFWorkbook();
        try {
            String sheetName = data.getName();
            if (null == sheetName) {
                sheetName = "Sheet1";
            }
            XSSFSheet sheet = wb.createSheet(sheetName);
            writeExcel(wb, sheet, data);

            wb.write(out);
        } finally {
            wb.close();
        }
    }

    private static void writeExcel(XSSFWorkbook wb, Sheet sheet, ExcelData data) {

        int rowIndex = 0;

        rowIndex = writeTitlesToExcel(wb, sheet, data.getTitles());
        writeRowsToExcel(wb, sheet, data.getRows(), rowIndex);
        autoSizeColumns(sheet, data.getTitles().size() + 1);

    }

    private static int writeTitlesToExcel(XSSFWorkbook wb, Sheet sheet, List<String> titles) {
        int rowIndex = 0;
        int colIndex = 0;

        Font titleFont = wb.createFont();
        titleFont.setFontName("simsun");
        titleFont.setBold(true);
        titleFont.setColor(IndexedColors.BLACK.index);

        XSSFCellStyle titleStyle = wb.createCellStyle();
        titleStyle.setFillForegroundColor(new XSSFColor(new Color(182, 184, 192)));
        titleStyle.setFont(titleFont);
        setBorder(titleStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));

        Row titleRow = sheet.createRow(rowIndex);
        colIndex = 0;

        for (String field : titles) {
            Cell cell = titleRow.createCell(colIndex);
            cell.setCellValue(field);
            cell.setCellStyle(titleStyle);
            colIndex++;
        }

        rowIndex++;
        return rowIndex;
    }

    private static int writeRowsToExcel(XSSFWorkbook wb, Sheet sheet, List<List<Object>> rows, int rowIndex) {
        int colIndex = 0;

        Font dataFont = wb.createFont();
        dataFont.setFontName("simsun");
        dataFont.setColor(IndexedColors.BLACK.index);

        XSSFCellStyle dataStyle = wb.createCellStyle();
        dataStyle.setFont(dataFont);
        setBorder(dataStyle, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));

        XSSFCellStyle cellStyleNumber = wb.createCellStyle();

        for (List<Object> rowData : rows) {
            Row dataRow = sheet.createRow(rowIndex);
            colIndex = 0;

            for (Object cellData : rowData) {
                Cell cell =null;
                //先处理数字带小数的数据
                if( cellData!=null && StringUtil.isNotEmpty(cellData.toString()) && cellData.toString().contains(".")&& isNumeric(cellData.toString())){
                    cell = dataRow.createCell(colIndex, Cell.CELL_TYPE_NUMERIC);
                    XSSFDataFormat dff = wb.createDataFormat();  //此处设置数据格式
                    //获取小数位数
                    String inStr=cellData.toString();
                    //获取小数点的位置
                    int bitPos=inStr.indexOf(".");
                    //字符串总长度减去小数点位置，再减去1，就是小数位数
                    int numOfBits=inStr.length()-bitPos-1;
                    if( numOfBits<4){
                        cellStyleNumber.setDataFormat(dff.getFormat("#0.00")); //小数点后保留两位，可以写contentStyle.setDataFormat(df.getFormat("#,#0.00"));
                    }else{
                        cellStyleNumber.setDataFormat(dff.getFormat("#0.0000")); //小数点后保留两位，可以写contentStyle.setDataFormat(df.getFormat("#,#0.00"));
                    }

                    cellStyleNumber.setFont(dataFont);
                    setBorder(cellStyleNumber, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));
                    cell.setCellStyle(cellStyleNumber);
                    cell.setCellValue(Double.valueOf( cellData.toString()));
                }else{
                    //再数量
                    if( cellData instanceof BigDecimal || cellData instanceof Long || cellData instanceof Double || cellData instanceof Float || cellData instanceof Short || cellData instanceof Integer){
                        cell = dataRow.createCell(colIndex, Cell.CELL_TYPE_NUMERIC);
                        XSSFDataFormat dff = wb.createDataFormat();  //此处设置数据格式
                        cellStyleNumber.setDataFormat(dff.getFormat("")); //小数点后保留两位，可以写contentStyle.setDataFormat(df.getFormat("#,#0.00"));
                        cell.setCellStyle(cellStyleNumber);
                        cellStyleNumber.setFont(dataFont);
                        setBorder(cellStyleNumber, BorderStyle.THIN, new XSSFColor(new Color(0, 0, 0)));
                        cell.setCellValue(Double.valueOf( cellData.toString()));
                    }else{
                        cell = dataRow.createCell(colIndex);
                        if (cellData != null) {
                            cell.setCellValue(cellData.toString());
                        } else {
                            cell.setCellValue("");
                        }
                        cell.setCellStyle(dataStyle);
                    }
                }
                colIndex++;
            }
            rowIndex++;
        }
        return rowIndex;
    }

    /**
     * 利用正则表达式判断字符串是否是数字
     * @param str
     * @return
     */
    public static boolean isNumeric(String str){
        String regex="^[+-]?\\d+(\\.\\d+)?$";
        if(str.matches(regex)==true){
            return true;
        }else{
            return false;
        }
    }

    private static void autoSizeColumns(Sheet sheet, int columnNumber) {

        for (int i = 0; i < columnNumber; i++) {
            int orgWidth = sheet.getColumnWidth(i);
            sheet.autoSizeColumn(i, true);
            int newWidth = (int) (sheet.getColumnWidth(i) + 100);
            //避免超出范围
            if (newWidth > 65280 || orgWidth >65280) {
                sheet.setColumnWidth(i, 65280);
            }
            else if (newWidth > orgWidth) {
                sheet.setColumnWidth(i, newWidth);
            } else {
                sheet.setColumnWidth(i, orgWidth);
            }
        }
    }

    private static void setBorder(XSSFCellStyle style, BorderStyle border, XSSFColor color) {
        style.setBorderTop(border);
        style.setBorderLeft(border);
        style.setBorderRight(border);
        style.setBorderBottom(border);
        style.setBorderColor(XSSFCellBorder.BorderSide.TOP, color);
        style.setBorderColor(XSSFCellBorder.BorderSide.LEFT, color);
        style.setBorderColor(XSSFCellBorder.BorderSide.RIGHT, color);
        style.setBorderColor(XSSFCellBorder.BorderSide.BOTTOM, color);
    }
}

导出调用

	@PostMapping(value = "/excel")
    public void export(HttpServletResponse response, @ModelAttribute CertificateExportModel model) throws Exception {
        log.info("[/user/excel]: 用户信息导出, 请求参数：{}", model);
        LambdaQueryWrapper<User> condition = new LambdaQueryWrapper<>();
        if (StrUtil.isNotEmpty(model.getNameCn())) {
            condition.eq(CertificationRecord::getNameCn, model.getNameCn());
        }
        List<User> records = userService.list(condition);

        ExcelData data = new ExcelData();
        data.setName("用户信息");
        List<String> titles = new ArrayList();
        titles.add("id");
        titles.add("姓名");
        titles.add("英文姓");
        titles.add("英文名");
        titles.add("性别 (0:女 1:男)");
        data.setTitles(titles);

        List<List<Object>> rows = new ArrayList();
        records.forEach(u -> {
            List<Object> row = new ArrayList();
            row.add(u.getId());
            row.add(u.getNameCn());
            row.add(u.getSurnameen());
            row.add(u.getNameEn());
            row.add(u.getSex());
            rows.add(row);
        });
        data.setRows(rows);

        ExportExcelUtils.exportExcel(response, "用户信息.xlsx", data);
    }

以上。