HttpURLConnection从链接下载数据存放本地临时文件，Java

迷南。 2024-04-08 10:25 58阅读 0赞

private File download(String url) throws Exception {
            HttpURLConnection connection = getConnection(url);
    
            int contentLength = connection.getContentLength();
    
            String msg = connection.getResponseMessage();
            System.out.println(msg);
    
            InputStream is = connection.getInputStream();
            BufferedInputStream bis = new BufferedInputStream(is);
            File tempFile = File.createTempFile(UUID.randomUUID().toString(), "");
            FileOutputStream fos = new FileOutputStream(tempFile);
            BufferedOutputStream bos = new BufferedOutputStream(fos);
    
            int c;
            int count = 0;
            byte[] buf = new byte[1024 * 4];
            double pcent;
            while (true) {
                c = bis.read(buf);
                if (c == -1)
                    break;
                bos.write(buf, 0, c);
    
                count = count + c;
    
                pcent = (count / (double) contentLength) * 100;
                System.out.print("已下载:" + String.format("%.2f", pcent) + "% \r");
            }
    
            bis.close();
            bos.close();
            fos.close();
    
            return tempFile;
        }
    
        private HttpURLConnection getConnection(String u) throws Exception {
            URL url = new URL(u);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestProperty("Connection", "Keep-Alive");
            connection.connect();
    
            return connection;
        }