如何用Java在线下载mp3文件？

Question

我使用以下方法下载mp3文件:http: //online1.tingclass.com/lesson/shi0529/43/32.mp3

但是我收到以下错误:

java.io.FileNotFoundException:http:\ online1.tingclass.com\lesson\shi0529\43\32.mp3(文件名,目录名或卷标语法不正确)

  public static void Copy_File(String From_File,String To_File)
  {   
    try
    {
      FileChannel sourceChannel=new FileInputStream(From_File).getChannel();
      FileChannel destinationChannel=new FileOutputStream(To_File).getChannel();
      sourceChannel.transferTo(0,sourceChannel.size(),destinationChannel);
      // or
      //  destinationChannel.transferFrom(sourceChannel, 0, sourceChannel.size());
      sourceChannel.close();
      destinationChannel.close();
    }
    catch (Exception e) { e.printStackTrace(); }
  }

然而,如果我手动从浏览器中执行此操作,文件就在那里,我想知道它为什么不起作用,以及正确的方法是什么？

坦率

Answer 1

使用旧式Java IO,但您可以将其映射到您正在使用的NIO方法.关键是使用URLConnection.

    URLConnection conn = new URL("http://online1.tingclass.com/lesson/shi0529/43/32.mp3").openConnection();
    InputStream is = conn.getInputStream();

    OutputStream outstream = new FileOutputStream(new File("/tmp/file.mp3"));
    byte[] buffer = new byte[4096];
    int len;
    while ((len = is.read(buffer)) > 0) {
        outstream.write(buffer, 0, len);
    }
    outstream.close();