struts 2 poi上传文件

首先下载poi包jar

然后配置文件：

<action name="ExportExcelAction" class="GuessYouLikeAction" method="exceport" >
            <result name="excel" type="stream">
                <param name="contentType">application/vnd.ms-excel</param>
                <param name="contentDisposition">attachment;filename="${downloadFileName}"</param> 
                <param name="bufferSize">1024</param>
                <param name="inputName">excelFile</param>
            </result>
        </action>

action里面首先要有一个成员变量
private InputStream excelFile;
private String downloadFileName;

并且生成get set 方法如下：

public InputStream getExcelFile() {
        return excelFile;
    }
    public void setExcelFile(InputStream excelFile) {
        this.excelFile = excelFile;
    }
    public String getDownloadFileName() {
        SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd ");
        String downloadFileName = (sf.format(new Date()).toString())+ "结果列表.xls";
        try {
            downloadFileName = new String(downloadFileName.getBytes(),"ISO8859-1");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return downloadFileName;
    }
    public void setDownloadFileName(String downloadFileName) {
        this.downloadFileName = downloadFileName;
    }

然后就可以开始准备到处excel了，代码如下：

public String exceport()throws Exception {
        int a=0;
        System.out.println(a);
        List<ibas_guessyl_result> listRes =new ArrayList<ibas_guessyl_result>();
        try{
        listRes=guessYouLikeServiceImpl.searchGuessYouLikeExportExcel();
        }catch(Exception e){
            System.out.println(e);
        }
        HSSFWorkbook workbook = exportExcel(listRes);
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        workbook.write(output);
        byte[] ba = output.toByteArray();
        excelFile = new ByteArrayInputStream(ba);
        output.flush();
        output.close();
        return "excel";
    }

public HSSFWorkbook exportExcel(List<ibas_guessyl_result> dataList) throws Exception {
        HSSFWorkbook workbook = null;
        try {
            // 创建工作簿实例
            workbook = new HSSFWorkbook();
            // 创建工作表实例
            HSSFSheet sheet = workbook.createSheet("TscExcel");
            // 设置列宽
            this.setSheetColumnWidth(sheet);
            // 获取样式
            HSSFCellStyle style = this.createTitleStyle(workbook);
            if (dataList != null && dataList.size() > 0) {
                // 创建第一行标题,标题名字的本地信息通过resources从资源文件中获取
                System.out.println("开始生成excel");
                HSSFRow row = sheet.createRow((short) 0);// 建立新行
                this.createCell(row, 0, style, HSSFCell.CELL_TYPE_STRING,"序号");
                this.createCell(row, 1, style, HSSFCell.CELL_TYPE_STRING,"号码");
                this.createCell(row, 2, style, HSSFCell.CELL_TYPE_STRING,"品牌");
                this.createCell(row, 3, style, HSSFCell.CELL_TYPE_STRING,"地市");
                this.createCell(row, 4, style, HSSFCell.CELL_TYPE_STRING,"套餐");
                this.createCell(row, 5, style, HSSFCell.CELL_TYPE_STRING,"ARPU值");
                this.createCell(row, 6, style, HSSFCell.CELL_TYPE_STRING,"职业");
                this.createCell(row, 7, style, HSSFCell.CELL_TYPE_STRING,"互联网偏好");
                this.createCell(row, 8, style, HSSFCell.CELL_TYPE_STRING,"用户分群");
                this.createCell(row, 9, style, HSSFCell.CELL_TYPE_STRING,"主要活动区");
                System.out.println("!!!!sssssssssssssssss!!!!");
                // 给excel填充数据
                for (int i = 0; i < dataList.size(); i++) {
                    System.out.println("!!-------填充数据------!!");
                    // 将dataList里面的数据取出来，假设这里取出来的是Model,也就是某个javaBean的意思啦
                    ibas_guessyl_result model = (ibas_guessyl_result) dataList.get(i);
                    HSSFRow row1 = sheet.createRow((short) (i + 1));// 建立新行
                    this.createCell(row1, 0, style, HSSFCell.CELL_TYPE_STRING,i + 1);
                    if (model.getPhone_id() != 0)
                        this.createCell(row1, 1, style,HSSFCell.CELL_TYPE_STRING, model.getPhone_id());
                    if (model.getBrand_name() != null)
                        this.createCell(row1, 2, style,HSSFCell.CELL_TYPE_STRING, model.getBrand_name());
                    if (model.getC_city_name() != null)
                        this.createCell(row1, 3, style,HSSFCell.CELL_TYPE_STRING, model.getC_city_name());
                    if (model.getMain_pack_name() != null)
                        this.createCell(row1, 4, style,HSSFCell.CELL_TYPE_STRING, model.getMain_pack_name());
                    if (model.getArpu() != 0.0)
                        this.createCell(row1, 5, style,HSSFCell.CELL_TYPE_STRING, model.getArpu());
                    if (model.getJob() != null)
                        this.createCell(row1, 6, style,HSSFCell.CELL_TYPE_STRING, model.getJob());
                    if (model.getLabel_name() != null)
                        this.createCell(row1, 7, style,HSSFCell.CELL_TYPE_STRING, model.getLabel_name());
                    if (model.getGroup_name() != null)
                        this.createCell(row1, 7, style,HSSFCell.CELL_TYPE_STRING, model.getGroup_name());
                    if (model.getMain_act_community() != null)
                        this.createCell(row1, 7, style,HSSFCell.CELL_TYPE_STRING, model.getMain_act_community());
                    if(i%65500==0 && i!=0){
                        break;
                    }
                }
            } else {
                this.createCell(sheet.createRow(0), 0, style,
                        HSSFCell.CELL_TYPE_STRING, "查无资料");
                System.out.println("--------查无资料-------");
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("异常为----"+e);
        }
        return workbook;
    }

private void setSheetColumnWidth(HSSFSheet sheet) {
        // 根据你数据里面的记录有多少列，就设置多少列
        sheet.setColumnWidth(0, 3000);
        sheet.setColumnWidth(1, 8000);
        sheet.setColumnWidth(2, 3000);
        sheet.setColumnWidth(3, 8000);
        sheet.setColumnWidth(4, 8000);
        sheet.setColumnWidth(5, 5000);
        sheet.setColumnWidth(6, 5000);
        sheet.setColumnWidth(7, 5000);
        sheet.setColumnWidth(8, 5000);
        sheet.setColumnWidth(9, 5000);
        }

    // 设置excel的title样式

    private HSSFCellStyle createTitleStyle(HSSFWorkbook wb) {
    HSSFFont boldFont = wb.createFont();
    boldFont.setFontHeight((short) 200);
    HSSFCellStyle style = wb.createCellStyle();
    style.setFont(boldFont);
    style.setDataFormat(HSSFDataFormat.getBuiltinFormat("###,##0.00"));
    return style;
    }
    // 创建Excel单元格

    private void createCell(HSSFRow row, int column, HSSFCellStyle style,int cellType, Object value) {
        HSSFCell cell = row.createCell(column);

        if (style != null) {
            cell.setCellStyle(style);
        }
        switch (cellType) {
        case HSSFCell.CELL_TYPE_BLANK: {
        } break;
        case HSSFCell.CELL_TYPE_STRING: {
            cell.setCellValue(value.toString());
        } break;
        case HSSFCell.CELL_TYPE_NUMERIC: {
            cell.setCellType(HSSFCell.CELL_TYPE_NUMERIC);
            cell.setCellValue(Double.parseDouble(value.toString()));
        }    break;
        default:break;
        }
    }

以上就是到处excel 过程及其详细代码。