public void ajaxDownLoadSysManscript() throws IOException {

		
		List<SysattachmentVo> samvo = sysattachmentservice
				.ajaxgetSysattVoList(ids);
		if (samvo != null && samvo.size() > 0) {
			String FilePath = "D:\\";
			// 生成的ZIP文件名为Demo.zip
			String tmpFileName = "Demo.zip";
			String strZipPath = FilePath + tmpFileName;
			ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
					strZipPath));
			byte[] buffer = new byte[1024];
			for (int k = 0; k < samvo.size(); k++) {
				try {
					if (samvo.get(k).getSaAttachment() != null
							&& !"".equals(samvo.get(k).getSaAttachment())) {
						URL _URL = new URL(samvo.get(k).getSaAttachment());
						HttpURLConnection con = (HttpURLConnection) _URL
								.openConnection();

						// 获取文件名
						String trueurl = con.getURL().toString();
						String filenamestr = trueurl.substring(trueurl
								.lastIndexOf('/') + 1);
						String filet = filenamestr.substring(filenamestr
								.lastIndexOf('.'));
						String filename = samvo.get(k).getSaTitle() + filet;

						InputStream fis = new BufferedInputStream(con
								.getInputStream());
						out.putNextEntry(new ZipEntry(filename));
						// 设置压缩文件内的字符编码，不然会变成乱码
						out.setEncoding("GBK");
						int len;
						// 读入需要下载的文件的内容，打包到zip文件
						while ((len = fis.read(buffer)) > 0) {
							out.write(buffer, 0, len);
						}
						out.closeEntry();
						fis.close();

					}
				} catch (Exception e) {
					e.printStackTrace();
					continue;
				}
			}
			out.close();
			this.downFile(this.getResponse(), tmpFileName);
		}

	}

	/**
	 * 下载文件
	 * @param response
	 * @param str
	 */
	private void downFile(HttpServletResponse response, String str) {
		try {
			String FilePath = "D:\\";
			String path = FilePath + str;
			File file = new File(path);
			if (file.exists()) {
				InputStream ins = new FileInputStream(path);
				BufferedInputStream bins = new BufferedInputStream(ins);// 放到缓冲流里面
				OutputStream outs = response.getOutputStream();// 获取文件输出IO流
				BufferedOutputStream bouts = new BufferedOutputStream(outs);
				response.setContentType("application/x-download");// 设置response内容的类型
				response.setHeader("Content-disposition",
						"attachment;filename="
								+ URLEncoder.encode(str, "UTF-8"));// 设置头部信息
				int bytesRead = 0;
				byte[] buffer = new byte[8192];
				// 开始向网络传输文件流
				while ((bytesRead = bins.read(buffer, 0, 8192)) != -1) {
					bouts.write(buffer, 0, bytesRead);
				}
				bouts.flush();// 这里一定要调用flush()方法
				ins.close();
				bins.close();
				outs.close();
				bouts.close();
			} else {
				response.sendRedirect("../error.jsp");
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
	}