Question

Some times work throuw the proxy server and reading prom buffer content my program to think so more time… until i close them. How set program code that from some seconds if do not have any answer from server to take another server?

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();

i tried to use counter but it not work… What exception i can use to catch this situation by my control?

Answer 1

You need to use URLConnection.setReadTimeout. From the specification,

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.

As you can see, reads that time-out will throw SocketTimeoutException, which you can catch appropriately, e.g.

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 */
}

Note that you need to be careful when using readLine as above — this will strip all \r and \n from the input.