HttpURLConnection getInputStream:180秒后总是超时

Question

我试图以这种方式在非常慢的连接上下载文件:

    java.net.URL url = new URL("https://X.X.X.X:8443/path/2f6b88cf2b70ee933197edfc9627a9bc/");
    HttpURLConnection connection = (HttpURLConnection)  url.openConnection();
    connection.setRequestMethod("GET");
    connection.setDoOutput(true);
    connection.setConnectTimeout(240 * 1000);
    connection.setReadTimeout(240 * 1000);
    long start = System.currentTimeMillis();
    Files.copy(connection.getInputStream(), new File("test.zip").toPath());
    System.out.println("Time: "+((System.currentTimeMillis() - start) / 1000) + " sec.");

我注意到由于某些原因(本机Windows套接字超时？)它总是在下载180秒后中断,没有任何例外.

在setConnectTimeout(...)或setReadTimeout(...)中设置的超时没有帮助.

我尝试使用wget下载该文件:

wget https://X.X.X.X:8443/path/2f6b88cf2b70ee933197edfc9627a9bc/ --no-check-certificate
--2015-09-07 14:36:12--  https://X.X.X.X:8443/path/2f6b88cf2b70ee933197edfc9627a9bc/
Connecting to X.X.X.X:8443... connected.
WARNING: The certificate of ‘X.X.X.X’ is not trusted.
WARNING: The certificate of ‘X.X.X.X’ hasn't got a known issuer.
The certificate's owner does not match hostname ‘X.X.X.X’
HTTP request sent, awaiting response... 302 Found
Location: https://X.X.X.X:8443/files/test.zip [following]
--2015-09-07 14:36:16--  https://X.X.X.X:8443/files/test.zip
Reusing existing connection to X.X.X.X:8443.
HTTP request sent, awaiting response... 200 OK
Length: 321917584 (307M) [application/zip]
Saving to: ‘test.zip’

test.zip                                  100%[====================================================================================>] 307.00M   253KB/s   in 19m 50ss

20分钟后,完整文件已成功保存在磁盘上.

HttpURLConnection有什么问题？

编辑:我试图通过http协议从其他服务器下载测试文件,一切正常.它似乎是服务器或协议特定的问题.但为什么wget设法下载整个文件？

Edit2:按照你的建议我也尝试过:

• remove connection.setDoOutput(true);
• 使用直接链接来避免重定向302
• 通过自定义实现替换Files.copy方法

不幸的是,以上都没有帮助

Edit3:我注意到该文件也可以通过不安全的http协议在同一台服务器上使用.所以我只更改了代码中的URL,120秒后我得到了:

Exception in thread "main" java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:196)
    at java.net.SocketInputStream.read(SocketInputStream.java:122)
    at java.io.BufferedInputStream.read1(BufferedInputStream.java:273)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:334)
    at sun.net.www.MeteredStream.read(MeteredStream.java:134)
    at java.io.FilterInputStream.read(FilterInputStream.java:133)
    at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3066)
    at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3060)
    at java.nio.file.Files.copy(Files.java:2735)
    at java.nio.file.Files.copy(Files.java:2854) 

Answer 1

我终于在这里找到了解决方案It is not possible to download large files at Jetty server (再次感谢 StackOverflow)。问题出在服务器端。

我们使用的 Jetty 9.2 有一个错误，会中断在慢速连接上提供大文件的服务 ( https://bugs.eclipse.org/bugs/show_bug.cgi?id=472621 )。似乎并不总是抛出异常。

尽管传输停滞或连接重置，Wget 和浏览器仍能以某种方式完成下载。不幸的是我的 Java 应用程序更敏感......

将捆绑的 Jetty 升级到最新稳定版本 9.3.3 修复了所有下载问题。