简单的下载例子
前两天看代码，有一个下载的例子，我觉得写得挺全面的，所以就传上来，以后再需要些这样的例子就直接拿走了：
public void downLoad(@Read(key="url")String url){//获取参数int npos = url.lastIndexOf("/");//获取文件名String filename = url.substring(npos+1);int npos2 = filename.indexOf(".");//获取文件类型String filetype = filename.substring(npos2);HttpServletResponse response=this.getResponse();if (filetype.equalsIgnoreCase("doc")) { //doc文档 response.setHeader("Content-Type","application/msword");}else if (filetype.equalsIgnoreCase("xls")) { //xls文档 response.setHeader("Content-Type","application/msexcel");}else if (filetype.equalsIgnoreCase("ppt")) { //ppt文档 response.setHeader("Content-Type","application/mspowerpoint");}else if (filetype.equalsIgnoreCase("pdf")) { //pdf文档 response.setHeader("Content-Type","application/pdf");}else if (filetype.equalsIgnoreCase("zip")) { //zip文档 response.setHeader("Content-Type","application/zip");}else if (filetype.equalsIgnoreCase("rar")) { //rar文档 response.setHeader("Content-Type","application/rar");}else if (filetype.equalsIgnoreCase("jpg")) { //jpg图片 response.setHeader("Content-Type","image/JPEG");}else if (filetype.equalsIgnoreCase("txt")) { //txt文档 response.setHeader("Content-Type","application/txt");}else { response.setHeader("Content-Type","application/x-msdownload");}PrintWriter out;try {OutputStream outputStream = response.getOutputStream();//读取文件来源//URL url_url = new URL(url);//HttpURLConnection connection = (HttpURLConnection) url_url.openConnection();//connection.connect();String rootPath = this.getServlet().getServletContext().getRealPath("/");String path = rootPath + url;//String path=rootPath+"Modules/downloads/agentcontract/space.txt";System.out.println(path);InputStream inputStream = new FileInputStream(path);;response.setHeader("Pragma", "no-cache");//response.setContentType("application/x-download");//response.setHeader("Location",url);response.setHeader("Content-Disposition", "attachment; filename="+ filename);//response.setContentLength(filelength);byte[] buffer = new byte[1024];int i = -1;while ((i = inputStream.read(buffer)) != -1) {outputStream.write(buffer, 0, i);}outputStream.flush();outputStream.close();inputStream.close();outputStream = null;out = response.getWriter();out.flush();//out = pageContext.pushBody();} catch (Exception e) {// TODO: handle exception}}