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protected void readFile(InputStream in, String fileName,
			HttpServletResponse response) {
		ServletOutputStream out = null;
		try {
			response
					.setContentType("application/octet-stream;charset=ISO8859-1");
			response.setHeader("Content-Disposition", "attachment;filename="
					+ fileName);
			out = response.getOutputStream();
			byte[] b = new byte[100];
			while (in.read(b) != -1) {
				out.write(b);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				if (in != null) {
					in.close();
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
			try {
				if (out != null) {
					out.close();
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}