java - 代理人。思考过程。我怎样才能杀死他们？

Question

有时，我的程序会通过代理服务器并读取舞会缓冲区内容来思考更多时间......直到我关闭它们。如何设置程序代码，在几秒钟内如果没有来自服务器的任何答复，则采取另一台服务器？

URL url = new URL(linkCar);
String your_proxy_host = new String(proxys.getValueAt(xProxy, 1).toString());
int your_proxy_port = Integer.parseInt(proxys.getValueAt(xProxy, 2).toString());
Proxy proxy = null;
//  System.out.println(proxys.getValueAt(xProxy, 3).toString());
//  if (proxys.getValueAt(xProxy, 3).toString().indexOf("HTTP") > 0)
//  {
proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(your_proxy_host, your_proxy_port));
//  } else {
//  proxy = new Proxy(Proxy.Type.SOCKS, new InetSocketAddress(your_proxy_host, your_proxy_port));
//  }

HttpURLConnection connection = (HttpURLConnection)url.openConnection(proxy);
connection.setConnectTimeout(1000);
connection.connect();

String line = null;
StringBuffer buffer_page = new StringBuffer();
BufferedReader buffer_input = new BufferedReader(new InputStreamReader(connection.getInputStream(),"cp1251")); 
int cc = 0;

//this is thinking place!!!
while ((line = buffer_input.readLine()) != null && cc < 7000) {
   buffer_page.append(line);
   cc++;
}

doc = Jsoup.parse(String.valueOf(buffer_page));
connection.disconnect();

我尝试使用计数器，但它不起作用...我可以使用什么异常来通过我的控制捕获这种情况？

Answer 1

您需要使用URLConnection.setReadTimeout 。从规范来看，

Sets the read timeout to a specified timeout, in milliseconds. A non-zero value specifies the timeout when reading from Input stream when a connection is established to a resource. If the timeout expires before there is data available for read, a java.net.SocketTimeoutException is raised. A timeout of zero is interpreted as an infinite timeout.

如您所见，读取超时将抛出 SocketTimeoutException ，您可以适本地捕获，例如

try (BufferedReader buffer_input = new BufferedReader(
         new InputStreamReader(connection.getInputStream(), "cp1251"))) {
  String line;
  while ((line = buffer_input.readLine()) != null) {
    buffer_page.append(line);
  }
} catch (SocketTimeoutException ex) {
  /* handle time-out */
}

请注意，如上所述使用 readLine 时需要小心 - 这将从输入中删除所有 \r 和 \n .