Java URLConnection超时

Question

我正在尝试从HTTP URL解析XML文件。如果XML fetch花费的时间超过15秒，我希望将超时设置为15秒，我希望报告超时。由于某些原因，setConnectTimeout和setReadTimeout无法工作。代码如下：

          URL url = new URL("http://www.myurl.com/sample.xml");
          URLConnection urlConn = url.openConnection();
          urlConn.setConnectTimeout(15000);
          urlConn.setReadTimeout(15000);
          urlConn.setAllowUserInteraction(false);         
          urlConn.setDoOutput(true);

          InputStream inStream = urlConn.getInputStream();
          InputSource input = new InputSource(inStream);

我要赶上SocketTimeoutException了。

谢谢，克里斯

Answer 1

试试这个：

       import java.net.HttpURLConnection;

       URL url = new URL("http://www.myurl.com/sample.xml");

       HttpURLConnection huc = (HttpURLConnection) url.openConnection();
       HttpURLConnection.setFollowRedirects(false);
       huc.setConnectTimeout(15 * 1000);
       huc.setRequestMethod("GET");
       huc.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 (.NET CLR 3.5.30729)");
       huc.connect();
       InputStream input = huc.getInputStream();

或

       import org.jsoup.nodes.Document;

       Document doc = null;
       try {
           doc = Jsoup.connect("http://www.myurl.com/sample.xml").get();
       } catch (Exception e) {
           //log error
       }

然后看看如何使用Jsoup：http://jsoup.org/cookbook/input/load-document-from-url

Answer 2

您可以通过线程睡眠手动强制断开连接。这是一个示例：

URLConnection con = url.openConnection();
con.setConnectTimeout(5000);
con.setReadTimeout(5000);
new Thread(new InterruptThread(con)).start();

然后

public class InterruptThread implements Runnable {

    HttpURLConnection con;
    public InterruptThread(HttpURLConnection con) {
        this.con = con;
    }

    public void run() {
        try {
            Thread.sleep(5000); // or Thread.sleep(con.getConnectTimeout())
        } catch (InterruptedException e) {

        }
        con.disconnect();
        System.out.println("Timer thread forcing to quit connection");
    }
}

Answer 3

您可以通过更改以下系统属性为从jvm建立的所有连接设置超时：

System.setProperty("sun.net.client.defaultConnectTimeout", "10000");
System.setProperty("sun.net.client.defaultReadTimeout", "10000");

每次连接都会在10秒后超时。

不需要设置'defaultReadTimeout‘，但如果您需要控制读取，请将其作为示例显示。