POI动态导出EXCEL

 

/**
 * 利用开源组件POI3.0.2动态导出EXCEL文档
 *
 * @author 朱鹏飞
 * @version v1.0
 * @param <T>
 *
 */
public class ExportExcel<T> {

    public void exportExcel(Collection<T> dataset, OutputStream out) {
        exportExcel("对账单EXCEL文档", null, dataset, out, "yyyy-MM-dd");
    }

    public void exportExcel(String[] headers, Collection<T> dataset,
            OutputStream out) {
        exportExcel("对账单EXCEL文档", headers, dataset, out, "yyyy-MM-dd");
    }

    public void exportExcel(String[] headers, Collection<T> dataset,
            OutputStream out, String pattern) {
        exportExcel("对账单EXCEL文档", headers, dataset, out, pattern);
    }

    /**
     * 这是一个通用的方法，利用了JAVA的反射机制，可以将放置在JAVA集合中并且符合一定条件的数据以EXCEL 的形式输出到指定IO设备上
     *
     * @param title
     *            表格标题名
     * @param headers
     *            表格属性列名数组
     * @param dataset
     *            需要显示的数据集合,集合中一定要放置符合javabean风格的类的对象。此方法支持的
     *            javabean属性的数据类型有基本数据类型及String,Date,byte[](图片数据)
     * @param out
     *            与输出设备关联的流对象，可以将EXCEL文档导出到本地文件或者网络中
     * @param pattern
     *            如果有时间数据，设定输出格式。默认为"yyy-MM-dd"
     */
    @SuppressWarnings({ "unchecked", "deprecation" })
    public void exportExcel(String title, String[] headers,
            Collection<T> dataset, OutputStream out, String pattern) {
        // 声明一个工作薄
        HSSFWorkbook workbook = new HSSFWorkbook();
        // 生成一个表格
        HSSFSheet sheet = workbook.createSheet(title);
        // 设置表格默认列宽度为15个字节
        sheet.setDefaultColumnWidth((short) 15);
        // 生成一个样式
        HSSFCellStyle style = workbook.createCellStyle();
        // 设置这些样式
        style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
        style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
        style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        style.setBorderRight(HSSFCellStyle.BORDER_THIN);
        style.setBorderTop(HSSFCellStyle.BORDER_THIN);
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        // 生成一个字体
        HSSFFont font = workbook.createFont();
        font.setColor(HSSFColor.VIOLET.index);
        font.setFontHeightInPoints((short) 12);
        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        // 把字体应用到当前的样式
        style.setFont(font);
        // 生成并设置另一个样式
      HSSFCellStyle style2 = workbook.createCellStyle();
     style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);
     style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
     style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);
     style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);
     style2.setBorderRight(HSSFCellStyle.BORDER_THIN);
     style2.setBorderTop(HSSFCellStyle.BORDER_THIN);
     style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
     style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
     // 生成另一个字体
     HSSFFont font2 = workbook.createFont();
      font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
      // 把字体应用到当前的样式
      style2.setFont(font2);

        // 产生表格标题行
        HSSFRow row = sheet.createRow(0);
        for (short i = 0; i < headers.length; i++) {
            HSSFCell cell = row.createCell(i);
            cell.setCellStyle(style);
            HSSFRichTextString text = new HSSFRichTextString(headers[i]);
            cell.setCellValue(text);
        }

        // 遍历集合数据，产生数据行
        Iterator<T> it = dataset.iterator();
        int index = 0;
        while (it.hasNext()) {
            index++;
            row = sheet.createRow(index);
            T t = (T) it.next();
            // 利用反射，根据javabean属性的先后顺序，动态调用getXxx()方法得到属性值
            Field[] fields = t.getClass().getDeclaredFields();
            for (short i = 0; i < fields.length; i++) {
                HSSFCell cell = row.createCell(i);
//              cell.setCellStyle(style2);
                Field field = fields[i];
                String fieldName = field.getName();
                String getMethodName = "get"
                        + fieldName.substring(0, 1).toUpperCase()
                        + fieldName.substring(1);
                try {
                    Class tCls = t.getClass();
                    Method getMethod = tCls.getMethod(getMethodName,
                            new Class[] {});
                    Object value = getMethod.invoke(t, new Object[] {});
                    // 判断值的类型后进行强制类型转换
                    String textValue = null;

                    if (value instanceof Date) {
                        Date date = (Date) value;
                        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
                        textValue = sdf.format(date);
                    } else {
                        // 其它数据类型都当作字符串简单处理
                        textValue = value.toString();
                    }
                    // 利用正则表达式判断textValue是否全部由数字组成
                    if (textValue != null) {
                        Pattern p = Pattern.compile("^//d+(//.//d+)?{1}quot");
                        Matcher matcher = p.matcher(textValue);
                        if (matcher.matches()) {
                            // 是数字当作double处理
                            cell.setCellValue(Double.parseDouble(textValue));
                        } else {
                            HSSFRichTextString richString = new HSSFRichTextString(
                                    textValue);
                            HSSFFont font3 = workbook.createFont();
                            font3.setColor(HSSFColor.BLUE.index);
                            richString.applyFont(font3);
                            cell.setCellValue(richString);
                        }
                    }
                } catch (SecurityException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (NoSuchMethodException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IllegalArgumentException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (InvocationTargetException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } finally {
                    // 清理资源
                }
            }

        }
        try {
            workbook.write(out);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    public static void main(String[] args) throws IOException {
        ExportExcel<ReportBillsModel> ex = new ExportExcel<ReportBillsModel>();
        String[] headers = { "估价编号", "抵押物地址", "主贷人姓名", "支行名称", "扣款金额",
                "中介公司名字", "扣款时间" };
        List<ReportBillsModel> ls = new ArrayList<ReportBillsModel>();
        ReportBillsModel rm = new ReportBillsModel();
        rm.setAgentName("test");
        rm.setBankName("bank");
        rm.setCheckTime("1992-21-21");
        rm.setCreditorName("aa");
        rm.setDeductionAmount(21);
        rm.setDeductionTime("2012-12-12");
        rm.setEstimationCode("aadf");
        rm.setResidenceAddr("aaaaaaaaaaaaa");

        ls.add(rm);
        try {
            OutputStream out = new FileOutputStream("E://a.xls");
            ex.exportExcel(headers, ls, out);
            out.close();

            System.out.println("excel导出成功！");
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

 如果是web应用程序，做成下载的功能，代码如下：

 

HttpServletResponse response = getResponse();
        response.setContentType("application/octet-stream");
        String fileName = URLEncoder.encode("bills.xls",
                "UTF-8");
        String contentDisposition = "attachment; filename=" + fileName;
        response.setHeader("Content-Disposition", contentDisposition);
        ExportExcel<ReportBillsModel> ex = new ExportExcel<ReportBillsModel>();
        OutputStream out = response.getOutputStream();
        ex.exportExcel(headers, rbmList, out);
        out.close();