上传和下载

public HttpServletResponse download(String path, HttpServletResponse response) {  
        try {  
            // path是指欲下载的文件的路径。  
            File file = new File(path);  
            // 取得文件名。  
            String filename = file.getName();  
            // 取得文件的后缀名。  
            String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();  
 
            // 以流的形式下载文件。  
            InputStream fis = new BufferedInputStream(new FileInputStream(path));  
            byte[] buffer = new byte[fis.available()];  
            fis.read(buffer);  
            fis.close();  
            // 清空response  
            response.reset();  
            // 设置response的Header  
            response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));  
            response.addHeader("Content-Length", "" + file.length());  
            OutputStream toClient = new BufferedOutputStream(response.getOutputStream());  
            response.setContentType("application/octet-stream");  
            toClient.write(buffer);  
            toClient.flush();  
            toClient.close();  
        } catch (IOException ex) {  
            ex.printStackTrace();  
        }  
        return response;  
    }  
 
    public void downloadLocal(HttpServletResponse response) throws FileNotFoundException {  
        // 下载本地文件  
        String fileName = "Operator.doc".toString(); // 文件的默认保存名  
        // 读到流中  
        InputStream inStream = new FileInputStream("c:/Operator.doc");// 文件的存放路径  
        // 设置输出的格式  
        response.reset();  
        response.setContentType("bin");  
        response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");  
        // 循环取出流中的数据  
        byte[] b = new byte[100];  
        int len;  
        try {  
            while ((len = inStream.read(b)) > 0)  
                response.getOutputStream().write(b, 0, len);  
            inStream.close();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }  
 
    public void downloadNet(HttpServletResponse response) throws MalformedURLException {  
        // 下载网络文件  
        int bytesum = 0;  
        int byteread = 0;  
 
        URL url = new URL("windine.blogdriver.com/logo.gif");  
 
        try {  
            URLConnection conn = url.openConnection();  
            InputStream inStream = conn.getInputStream();  
            FileOutputStream fs = new FileOutputStream("c:/abc.gif");  
 
            byte[] buffer = new byte[1204];  
            int length;  
            while ((byteread = inStream.read(buffer)) != -1) {  
                bytesum += byteread;  
                System.out.println(bytesum);  
                fs.write(buffer, 0, byteread);  
            }  
        } catch (FileNotFoundException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    } 

public HttpServletResponse download(String path, HttpServletResponse response) {
        try {
            // path是指欲下载的文件的路径。
            File file = new File(path);
            // 取得文件名。
            String filename = file.getName();
            // 取得文件的后缀名。
            String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();

            // 以流的形式下载文件。
            InputStream fis = new BufferedInputStream(new FileInputStream(path));
            byte[] buffer = new byte[fis.available()];
            fis.read(buffer);
            fis.close();
            // 清空response
            response.reset();
            // 设置response的Header
            response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));
            response.addHeader("Content-Length", "" + file.length());
            OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
            response.setContentType("application/octet-stream");
            toClient.write(buffer);
            toClient.flush();
            toClient.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        return response;
    }

    public void downloadLocal(HttpServletResponse response) throws FileNotFoundException {
        // 下载本地文件
        String fileName = "Operator.doc".toString(); // 文件的默认保存名
        // 读到流中
        InputStream inStream = new FileInputStream("c:/Operator.doc");// 文件的存放路径
        // 设置输出的格式
        response.reset();
        response.setContentType("bin");
        response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
        // 循环取出流中的数据
        byte[] b = new byte[100];
        int len;
        try {
            while ((len = inStream.read(b)) > 0)
                response.getOutputStream().write(b, 0, len);
            inStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void downloadNet(HttpServletResponse response) throws MalformedURLException {
        // 下载网络文件
        int bytesum = 0;
        int byteread = 0;

        URL url = new URL("windine.blogdriver.com/logo.gif");

        try {
            URLConnection conn = url.openConnection();
            InputStream inStream = conn.getInputStream();
            FileOutputStream fs = new FileOutputStream("c:/abc.gif");

            byte[] buffer = new byte[1204];
            int length;
            while ((byteread = inStream.read(buffer)) != -1) {
                bytesum += byteread;
                System.out.println(bytesum);
                fs.write(buffer, 0, byteread);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

//支持在线打开文件的一种方式
Java代码
public void downLoad(String filePath, HttpServletResponse response, boolean isOnLine) throws Exception {  
        File f = new File(filePath);  
        if (!f.exists()) {  
            response.sendError(404, "File not found!");  
            return;  
        }  
        BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));  
        byte[] buf = new byte[1024];  
        int len = 0;  
 
        response.reset(); // 非常重要  
        if (isOnLine) { // 在线打开方式  
            URL u = new URL("file:///" + filePath);  
            response.setContentType(u.openConnection().getContentType());  
            response.setHeader("Content-Disposition", "inline; filename=" + f.getName());  
            // 文件名应该编码成UTF-8  
        } else { // 纯下载方式  
            response.setContentType("application/x-msdownload");  
            response.setHeader("Content-Disposition", "attachment; filename=" + f.getName());  
        }  
        OutputStream out = response.getOutputStream();  
        while ((len = br.read(buf)) > 0)  
            out.write(buf, 0, len);  
        br.close();  
        out.close();  
    } 
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