java之报表生成excel并提供下载

public InputStream getInputStream() { HSSFWorkbook wb = new HSSFWorkbook(); HSSFSheet sheet = wb.createSheet("sheet1"); HSSFRow row = sheet.createRow(0); HSSFCell cell = row.createCell((short) 0); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue("序号"); cell = row.createCell((short) 1); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue("姓"); cell = row.createCell((short) 2); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue("名"); cell = row.createCell((short) 3); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue("年龄"); List<User> list = this.findAll(); for (int i = 0; i < list.size(); ++i) { User user = list.get(i); row = sheet.createRow(i + 1); cell = row.createCell((short) 0); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue(i + 1); cell = row.createCell((short) 1); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue(user.getFirstname()); cell = row.createCell((short) 2); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue(user.getLastname()); cell = row.createCell((short) 3); cell.setEncoding(HSSFCell.ENCODING_UTF_16); cell.setCellValue(user.getAge()); } File file = new File("test.xls"); try { OutputStream os = new FileOutputStream(file); wb.write(os); os.close(); } catch (Exception e) { e.printStackTrace(); } InputStream is = null; try { is = new FileInputStream(file); } catch (FileNotFoundException e) { e.printStackTrace(); } return is; }

用到的包主要是Apache POI包，要想下载文件，首先把下载数据定义为一个输入输出流，里面的调用poi包里面的方法 HSSFWorkbook这个方法是创建一个工作表，也就是excel表，HSSFSheet是创建它的列，HSSFCell是创建它的行数，我用的是SSH框架，在里面要注意service里面要定义的下载名称要与struts配置文件里面的文件名一样才能成功下载，例 public InputStream getDownloadFile() { return this.userService.getInputStream(); }

那么下载的名字就应该是downloadFile,以下是struts XML配置

<action name="generateExcel" class="GenerateExcelAction"> <result name="success" type="stream"> <param name="contentType">application/vnd.ms-excel</param> <param name="contentDisposition">filename="ALLUser.xls"</param> <param name="inputName">downloadFile</param> </result> </action>

这样就能正确下载了。